Initial community commit

13 files changed, 4277 insertions, 0 deletions

diff --git a/Src/external_dependencies/giflib/dgif_lib.c b/Src/external_dependencies/giflib/dgif_lib.c
new file mode 100644
index 00000000..526d9dac
--- /dev/null
+++ b/Src/external_dependencies/giflib/dgif_lib.c
@@ -0,0 +1,1193 @@
+/******************************************************************************
+
+dgif_lib.c - GIF decoding
+
+The functions here and in egif_lib.c are partitioned carefully so that
+if you only require one of read and write capability, only one of these
+two modules will be linked.  Preserve this property!
+
+*****************************************************************************/
+
+#include <stdlib.h>
+#include <limits.h>
+#include <stdint.h>
+#include <fcntl.h>
+//#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+
+#ifdef _WIN32
+#include <io.h>
+#endif /* _WIN32 */
+
+#include "gif_lib.h"
+#include "gif_lib_private.h"
+
+/* compose unsigned little endian value */
+#define UNSIGNED_LITTLE_ENDIAN(lo, hi)	((lo) | ((hi) << 8))
+
+/* avoid extra function call in case we use fread (TVT) */
+#define READ(_gif,_buf,_len)                                     \
+  (((GifFilePrivateType*)_gif->Private)->Read ?                   \
+    ((GifFilePrivateType*)_gif->Private)->Read(_gif,_buf,_len) : \
+    fread(_buf,1,_len,((GifFilePrivateType*)_gif->Private)->File))
+
+static int DGifGetWord(GifFileType *GifFile, GifWord *Word);
+static int DGifSetupDecompress(GifFileType *GifFile);
+static int DGifDecompressLine(GifFileType *GifFile, GifPixelType *Line,
+                              int LineLen);
+static int DGifGetPrefixChar(GifPrefixType *Prefix, int Code, int ClearCode);
+static int DGifDecompressInput(GifFileType *GifFile, int *Code);
+static int DGifBufferedInput(GifFileType *GifFile, GifByteType *Buf,
+                             GifByteType *NextByte);
+
+/******************************************************************************
+ Open a new GIF file for read, given by its name.
+ Returns dynamically allocated GifFileType pointer which serves as the GIF
+ info record.
+******************************************************************************/
+GifFileType *
+DGifOpenFileName(const char *FileName, int *Error)
+{
+    int FileHandle;
+    GifFileType *GifFile;
+
+    if ((FileHandle = open(FileName, O_RDONLY)) == -1) {
+	if (Error != NULL)
+	    *Error = D_GIF_ERR_OPEN_FAILED;
+        return NULL;
+    }
+
+    GifFile = DGifOpenFileHandle(FileHandle, Error);
+    return GifFile;
+}
+
+/******************************************************************************
+ Update a new GIF file, given its file handle.
+ Returns dynamically allocated GifFileType pointer which serves as the GIF
+ info record.
+******************************************************************************/
+GifFileType *
+DGifOpenFileHandle(int FileHandle, int *Error)
+{
+    char Buf[GIF_STAMP_LEN + 1];
+    GifFileType *GifFile;
+    GifFilePrivateType *Private;
+    FILE *f;
+
+    GifFile = (GifFileType *)malloc(sizeof(GifFileType));
+    if (GifFile == NULL) {
+        if (Error != NULL)
+	    *Error = D_GIF_ERR_NOT_ENOUGH_MEM;
+        (void)close(FileHandle);
+        return NULL;
+    }
+
+    /*@i1@*/memset(GifFile, '\0', sizeof(GifFileType));
+
+    /* Belt and suspenders, in case the null pointer isn't zero */
+    GifFile->SavedImages = NULL;
+    GifFile->SColorMap = NULL;
+
+    Private = (GifFilePrivateType *)calloc(1, sizeof(GifFilePrivateType));
+    if (Private == NULL) {
+        if (Error != NULL)
+	    *Error = D_GIF_ERR_NOT_ENOUGH_MEM;
+        (void)close(FileHandle);
+        free((char *)GifFile);
+        return NULL;
+    }
+
+    /*@i1@*/memset(Private, '\0', sizeof(GifFilePrivateType));
+
+#ifdef _WIN32
+    _setmode(FileHandle, O_BINARY);    /* Make sure it is in binary mode. */
+#endif /* _WIN32 */
+
+    f = fdopen(FileHandle, "rb");    /* Make it into a stream: */
+
+    /*@-mustfreeonly@*/
+    GifFile->Private = (void *)Private;
+    Private->FileHandle = FileHandle;
+    Private->File = f;
+    Private->FileState = FILE_STATE_READ;
+    Private->Read = NULL;        /* don't use alternate input method (TVT) */
+    GifFile->UserData = NULL;    /* TVT */
+    /*@=mustfreeonly@*/
+
+    /* Let's see if this is a GIF file: */
+    /* coverity[check_return] */
+    if (READ(GifFile, (unsigned char *)Buf, GIF_STAMP_LEN) != GIF_STAMP_LEN) {
+        if (Error != NULL)
+	    *Error = D_GIF_ERR_READ_FAILED;
+        (void)fclose(f);
+        free((char *)Private);
+        free((char *)GifFile);
+        return NULL;
+    }
+
+    /* Check for GIF prefix at start of file */
+    Buf[GIF_STAMP_LEN] = 0;
+    if (strncmp(GIF_STAMP, Buf, GIF_VERSION_POS) != 0) {
+        if (Error != NULL)
+	    *Error = D_GIF_ERR_NOT_GIF_FILE;
+        (void)fclose(f);
+        free((char *)Private);
+        free((char *)GifFile);
+        return NULL;
+    }
+
+    if (DGifGetScreenDesc(GifFile) == GIF_ERROR) {
+        (void)fclose(f);
+        free((char *)Private);
+        free((char *)GifFile);
+        return NULL;
+    }
+
+    GifFile->Error = 0;
+
+    /* What version of GIF? */
+    Private->gif89 = (Buf[GIF_VERSION_POS] == '9');
+
+    return GifFile;
+}
+
+/******************************************************************************
+ GifFileType constructor with user supplied input function (TVT)
+******************************************************************************/
+GifFileType *
+DGifOpen(void *userData, InputFunc readFunc, int *Error)
+{
+    char Buf[GIF_STAMP_LEN + 1];
+    GifFileType *GifFile;
+    GifFilePrivateType *Private;
+
+    GifFile = (GifFileType *)malloc(sizeof(GifFileType));
+    if (GifFile == NULL) {
+        if (Error != NULL)
+	    *Error = D_GIF_ERR_NOT_ENOUGH_MEM;
+        return NULL;
+    }
+
+    memset(GifFile, '\0', sizeof(GifFileType));
+
+    /* Belt and suspenders, in case the null pointer isn't zero */
+    GifFile->SavedImages = NULL;
+    GifFile->SColorMap = NULL;
+
+    Private = (GifFilePrivateType *)calloc(1, sizeof(GifFilePrivateType));
+    if (!Private) {
+        if (Error != NULL)
+	    *Error = D_GIF_ERR_NOT_ENOUGH_MEM;
+        free((char *)GifFile);
+        return NULL;
+    }
+    /*@i1@*/memset(Private, '\0', sizeof(GifFilePrivateType));
+
+    GifFile->Private = (void *)Private;
+    Private->FileHandle = 0;
+    Private->File = NULL;
+    Private->FileState = FILE_STATE_READ;
+
+    Private->Read = readFunc;    /* TVT */
+    GifFile->UserData = userData;    /* TVT */
+
+    /* Lets see if this is a GIF file: */
+    /* coverity[check_return] */
+    if (READ(GifFile, (unsigned char *)Buf, GIF_STAMP_LEN) != GIF_STAMP_LEN) {
+        if (Error != NULL)
+	    *Error = D_GIF_ERR_READ_FAILED;
+        free((char *)Private);
+        free((char *)GifFile);
+        return NULL;
+    }
+
+    /* Check for GIF prefix at start of file */
+    Buf[GIF_STAMP_LEN] = '\0';
+    if (strncmp(GIF_STAMP, Buf, GIF_VERSION_POS) != 0) {
+        if (Error != NULL)
+	    *Error = D_GIF_ERR_NOT_GIF_FILE;
+        free((char *)Private);
+        free((char *)GifFile);
+        return NULL;
+    }
+
+    if (DGifGetScreenDesc(GifFile) == GIF_ERROR) {
+        free((char *)Private);
+        free((char *)GifFile);
+        if (Error != NULL)
+	    *Error = D_GIF_ERR_NO_SCRN_DSCR;
+        return NULL;
+    }
+
+    GifFile->Error = 0;
+
+    /* What version of GIF? */
+    Private->gif89 = (Buf[GIF_VERSION_POS] == '9');
+
+    return GifFile;
+}
+
+/******************************************************************************
+ This routine should be called before any other DGif calls. Note that
+ this routine is called automatically from DGif file open routines.
+******************************************************************************/
+int
+DGifGetScreenDesc(GifFileType *GifFile)
+{
+    int BitsPerPixel;
+    bool SortFlag;
+    GifByteType Buf[3];
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    if (!IS_READABLE(Private)) {
+        /* This file was NOT open for reading: */
+        GifFile->Error = D_GIF_ERR_NOT_READABLE;
+        return GIF_ERROR;
+    }
+
+    /* Put the screen descriptor into the file: */
+    if (DGifGetWord(GifFile, &GifFile->SWidth) == GIF_ERROR ||
+        DGifGetWord(GifFile, &GifFile->SHeight) == GIF_ERROR)
+        return GIF_ERROR;
+
+    if (READ(GifFile, Buf, 3) != 3) {
+        GifFile->Error = D_GIF_ERR_READ_FAILED;
+	GifFreeMapObject(GifFile->SColorMap);
+	GifFile->SColorMap = NULL;
+        return GIF_ERROR;
+    }
+    GifFile->SColorResolution = (((Buf[0] & 0x70) + 1) >> 4) + 1;
+    SortFlag = (Buf[0] & 0x08) != 0;
+    BitsPerPixel = (Buf[0] & 0x07) + 1;
+    GifFile->SBackGroundColor = Buf[1];
+    GifFile->AspectByte = Buf[2]; 
+    if (Buf[0] & 0x80) {    /* Do we have global color map? */
+	int i;
+
+        GifFile->SColorMap = GifMakeMapObject(1 << BitsPerPixel, NULL);
+        if (GifFile->SColorMap == NULL) {
+            GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
+            return GIF_ERROR;
+        }
+
+        /* Get the global color map: */
+	GifFile->SColorMap->SortFlag = SortFlag;
+        for (i = 0; i < GifFile->SColorMap->ColorCount; i++) {
+	    /* coverity[check_return] */
+            if (READ(GifFile, Buf, 3) != 3) {
+                GifFreeMapObject(GifFile->SColorMap);
+                GifFile->SColorMap = NULL;
+                GifFile->Error = D_GIF_ERR_READ_FAILED;
+                return GIF_ERROR;
+            }
+            GifFile->SColorMap->Colors[i].Red = Buf[0];
+            GifFile->SColorMap->Colors[i].Green = Buf[1];
+            GifFile->SColorMap->Colors[i].Blue = Buf[2];
+        }
+    } else {
+        GifFile->SColorMap = NULL;
+    }
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ This routine should be called before any attempt to read an image.
+******************************************************************************/
+int
+DGifGetRecordType(GifFileType *GifFile, GifRecordType* Type)
+{
+    GifByteType Buf;
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    if (!IS_READABLE(Private)) {
+        /* This file was NOT open for reading: */
+        GifFile->Error = D_GIF_ERR_NOT_READABLE;
+        return GIF_ERROR;
+    }
+
+    /* coverity[check_return] */
+    if (READ(GifFile, &Buf, 1) != 1) {
+        GifFile->Error = D_GIF_ERR_READ_FAILED;
+        return GIF_ERROR;
+    }
+
+    switch (Buf) {
+      case DESCRIPTOR_INTRODUCER:
+          *Type = IMAGE_DESC_RECORD_TYPE;
+          break;
+      case EXTENSION_INTRODUCER:
+          *Type = EXTENSION_RECORD_TYPE;
+          break;
+      case TERMINATOR_INTRODUCER:
+          *Type = TERMINATE_RECORD_TYPE;
+          break;
+      default:
+          *Type = UNDEFINED_RECORD_TYPE;
+          GifFile->Error = D_GIF_ERR_WRONG_RECORD;
+          return GIF_ERROR;
+    }
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ This routine should be called before any attempt to read an image.
+ Note it is assumed the Image desc. header has been read.
+******************************************************************************/
+int
+DGifGetImageDesc(GifFileType *GifFile)
+{
+    unsigned int BitsPerPixel;
+    GifByteType Buf[3];
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+    SavedImage *sp;
+
+    if (!IS_READABLE(Private)) {
+        /* This file was NOT open for reading: */
+        GifFile->Error = D_GIF_ERR_NOT_READABLE;
+        return GIF_ERROR;
+    }
+
+    if (DGifGetWord(GifFile, &GifFile->Image.Left) == GIF_ERROR ||
+        DGifGetWord(GifFile, &GifFile->Image.Top) == GIF_ERROR ||
+        DGifGetWord(GifFile, &GifFile->Image.Width) == GIF_ERROR ||
+        DGifGetWord(GifFile, &GifFile->Image.Height) == GIF_ERROR)
+        return GIF_ERROR;
+    if (READ(GifFile, Buf, 1) != 1) {
+        GifFile->Error = D_GIF_ERR_READ_FAILED;
+	GifFreeMapObject(GifFile->Image.ColorMap);
+	GifFile->Image.ColorMap = NULL;
+        return GIF_ERROR;
+    }
+    BitsPerPixel = (Buf[0] & 0x07) + 1;
+    GifFile->Image.Interlace = (Buf[0] & 0x40) ? true : false;
+
+    /* Setup the colormap */
+    if (GifFile->Image.ColorMap) {
+        GifFreeMapObject(GifFile->Image.ColorMap);
+        GifFile->Image.ColorMap = NULL;
+    }
+    /* Does this image have local color map? */
+    if (Buf[0] & 0x80)
+    {
+        unsigned int i;
+
+        GifFile->Image.ColorMap = GifMakeMapObject(1 << BitsPerPixel, NULL);
+        if (GifFile->Image.ColorMap == NULL) {
+            GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
+            return GIF_ERROR;
+        }
+
+        /* Get the image local color map: */
+        for (i = 0; i < GifFile->Image.ColorMap->ColorCount; i++) {
+	    /* coverity[check_return] */
+            if (READ(GifFile, Buf, 3) != 3) {
+                GifFreeMapObject(GifFile->Image.ColorMap);
+                GifFile->Error = D_GIF_ERR_READ_FAILED;
+                GifFile->Image.ColorMap = NULL;
+                return GIF_ERROR;
+            }
+            GifFile->Image.ColorMap->Colors[i].Red = Buf[0];
+            GifFile->Image.ColorMap->Colors[i].Green = Buf[1];
+            GifFile->Image.ColorMap->Colors[i].Blue = Buf[2];
+        }
+    }
+
+    if (GifFile->SavedImages) {
+        SavedImage* new_saved_images =
+            (SavedImage *)reallocarray(GifFile->SavedImages,
+                            (GifFile->ImageCount + 1), sizeof(SavedImage));
+        if (new_saved_images == NULL) {
+            GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
+            return GIF_ERROR;
+        }
+        GifFile->SavedImages = new_saved_images;
+    } else {
+        if ((GifFile->SavedImages =
+             (SavedImage *) malloc(sizeof(SavedImage))) == NULL) {
+            GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
+            return GIF_ERROR;
+        }
+    }
+
+    sp = &GifFile->SavedImages[GifFile->ImageCount];
+    memcpy(&sp->ImageDesc, &GifFile->Image, sizeof(GifImageDesc));
+    if (GifFile->Image.ColorMap != NULL) {
+        sp->ImageDesc.ColorMap = GifMakeMapObject(
+                                 GifFile->Image.ColorMap->ColorCount,
+                                 GifFile->Image.ColorMap->Colors);
+        if (sp->ImageDesc.ColorMap == NULL) {
+            GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
+            return GIF_ERROR;
+        }
+    }
+    sp->RasterBits = (unsigned char *)NULL;
+    sp->ExtensionBlockCount = 0;
+    sp->ExtensionBlocks = (ExtensionBlock *) NULL;
+
+    GifFile->ImageCount++;
+
+    Private->PixelCount = (long)GifFile->Image.Width *
+       (long)GifFile->Image.Height;
+
+    /* Reset decompress algorithm parameters. */
+    return DGifSetupDecompress(GifFile);
+}
+
+/******************************************************************************
+ Get one full scanned line (Line) of length LineLen from GIF file.
+******************************************************************************/
+int
+DGifGetLine(GifFileType *GifFile, GifPixelType *Line, int LineLen)
+{
+    GifByteType *Dummy;
+    GifFilePrivateType *Private = (GifFilePrivateType *) GifFile->Private;
+
+    if (!IS_READABLE(Private)) {
+        /* This file was NOT open for reading: */
+        GifFile->Error = D_GIF_ERR_NOT_READABLE;
+        return GIF_ERROR;
+    }
+
+    if (!LineLen)
+        LineLen = GifFile->Image.Width;
+
+    if ((Private->PixelCount -= LineLen) > 0xffff0000UL) {
+        GifFile->Error = D_GIF_ERR_DATA_TOO_BIG;
+        return GIF_ERROR;
+    }
+
+    if (DGifDecompressLine(GifFile, Line, LineLen) == GIF_OK) {
+        if (Private->PixelCount == 0) {
+            /* We probably won't be called any more, so let's clean up
+             * everything before we return: need to flush out all the
+             * rest of image until an empty block (size 0)
+             * detected. We use GetCodeNext.
+	     */
+            do
+                if (DGifGetCodeNext(GifFile, &Dummy) == GIF_ERROR)
+                    return GIF_ERROR;
+            while (Dummy != NULL) ;
+        }
+        return GIF_OK;
+    } else
+        return GIF_ERROR;
+}
+
+/******************************************************************************
+ Put one pixel (Pixel) into GIF file.
+******************************************************************************/
+int
+DGifGetPixel(GifFileType *GifFile, GifPixelType Pixel)
+{
+    GifByteType *Dummy;
+    GifFilePrivateType *Private = (GifFilePrivateType *) GifFile->Private;
+
+    if (!IS_READABLE(Private)) {
+        /* This file was NOT open for reading: */
+        GifFile->Error = D_GIF_ERR_NOT_READABLE;
+        return GIF_ERROR;
+    }
+    if (--Private->PixelCount > 0xffff0000UL)
+    {
+        GifFile->Error = D_GIF_ERR_DATA_TOO_BIG;
+        return GIF_ERROR;
+    }
+
+    if (DGifDecompressLine(GifFile, &Pixel, 1) == GIF_OK) {
+        if (Private->PixelCount == 0) {
+            /* We probably won't be called any more, so let's clean up
+             * everything before we return: need to flush out all the
+             * rest of image until an empty block (size 0)
+             * detected. We use GetCodeNext.
+	     */
+            do
+                if (DGifGetCodeNext(GifFile, &Dummy) == GIF_ERROR)
+                    return GIF_ERROR;
+            while (Dummy != NULL) ;
+        }
+        return GIF_OK;
+    } else
+        return GIF_ERROR;
+}
+
+/******************************************************************************
+ Get an extension block (see GIF manual) from GIF file. This routine only
+ returns the first data block, and DGifGetExtensionNext should be called
+ after this one until NULL extension is returned.
+ The Extension should NOT be freed by the user (not dynamically allocated).
+ Note it is assumed the Extension description header has been read.
+******************************************************************************/
+int
+DGifGetExtension(GifFileType *GifFile, int *ExtCode, GifByteType **Extension)
+{
+    GifByteType Buf;
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    if (!IS_READABLE(Private)) {
+        /* This file was NOT open for reading: */
+        GifFile->Error = D_GIF_ERR_NOT_READABLE;
+        return GIF_ERROR;
+    }
+
+    /* coverity[check_return] */
+    if (READ(GifFile, &Buf, 1) != 1) {
+        GifFile->Error = D_GIF_ERR_READ_FAILED;
+        return GIF_ERROR;
+    }
+    *ExtCode = Buf;
+
+    return DGifGetExtensionNext(GifFile, Extension);
+}
+
+/******************************************************************************
+ Get a following extension block (see GIF manual) from GIF file. This
+ routine should be called until NULL Extension is returned.
+ The Extension should NOT be freed by the user (not dynamically allocated).
+******************************************************************************/
+int
+DGifGetExtensionNext(GifFileType *GifFile, GifByteType ** Extension)
+{
+    GifByteType Buf;
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    if (READ(GifFile, &Buf, 1) != 1) {
+        GifFile->Error = D_GIF_ERR_READ_FAILED;
+        return GIF_ERROR;
+    }
+    if (Buf > 0) {
+        *Extension = Private->Buf;    /* Use private unused buffer. */
+        (*Extension)[0] = Buf;  /* Pascal strings notation (pos. 0 is len.). */
+	/* coverity[tainted_data,check_return] */
+        if (READ(GifFile, &((*Extension)[1]), Buf) != Buf) {
+            GifFile->Error = D_GIF_ERR_READ_FAILED;
+            return GIF_ERROR;
+        }
+    } else
+        *Extension = NULL;
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ Extract a Graphics Control Block from raw extension data
+******************************************************************************/
+
+int DGifExtensionToGCB(const size_t GifExtensionLength,
+		       const GifByteType *GifExtension,
+		       GraphicsControlBlock *GCB)
+{
+    if (GifExtensionLength != 4) {
+	return GIF_ERROR;
+    }
+
+    GCB->DisposalMode = (GifExtension[0] >> 2) & 0x07;
+    GCB->UserInputFlag = (GifExtension[0] & 0x02) != 0;
+    GCB->DelayTime = UNSIGNED_LITTLE_ENDIAN(GifExtension[1], GifExtension[2]);
+    if (GifExtension[0] & 0x01)
+	GCB->TransparentColor = (int)GifExtension[3];
+    else
+	GCB->TransparentColor = NO_TRANSPARENT_COLOR;
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ Extract the Graphics Control Block for a saved image, if it exists.
+******************************************************************************/
+
+int DGifSavedExtensionToGCB(GifFileType *GifFile,
+			    int ImageIndex, GraphicsControlBlock *GCB)
+{
+    int i;
+
+    if (ImageIndex < 0 || ImageIndex > GifFile->ImageCount - 1)
+	return GIF_ERROR;
+
+    GCB->DisposalMode = DISPOSAL_UNSPECIFIED;
+    GCB->UserInputFlag = false;
+    GCB->DelayTime = 0;
+    GCB->TransparentColor = NO_TRANSPARENT_COLOR;
+
+    for (i = 0; i < GifFile->SavedImages[ImageIndex].ExtensionBlockCount; i++) {
+	ExtensionBlock *ep = &GifFile->SavedImages[ImageIndex].ExtensionBlocks[i];
+	if (ep->Function == GRAPHICS_EXT_FUNC_CODE)
+	    return DGifExtensionToGCB(ep->ByteCount, ep->Bytes, GCB);
+    }
+
+    return GIF_ERROR;
+}
+
+/******************************************************************************
+ This routine should be called last, to close the GIF file.
+******************************************************************************/
+int
+DGifCloseFile(GifFileType *GifFile, int *ErrorCode)
+{
+    GifFilePrivateType *Private;
+
+    if (GifFile == NULL || GifFile->Private == NULL)
+        return GIF_ERROR;
+
+    if (GifFile->Image.ColorMap) {
+        GifFreeMapObject(GifFile->Image.ColorMap);
+        GifFile->Image.ColorMap = NULL;
+    }
+
+    if (GifFile->SColorMap) {
+        GifFreeMapObject(GifFile->SColorMap);
+        GifFile->SColorMap = NULL;
+    }
+
+    if (GifFile->SavedImages) {
+        GifFreeSavedImages(GifFile);
+        GifFile->SavedImages = NULL;
+    }
+
+    GifFreeExtensions(&GifFile->ExtensionBlockCount, &GifFile->ExtensionBlocks);
+
+    Private = (GifFilePrivateType *) GifFile->Private;
+
+    if (!IS_READABLE(Private)) {
+        /* This file was NOT open for reading: */
+	if (ErrorCode != NULL)
+	    *ErrorCode = D_GIF_ERR_NOT_READABLE;
+	free((char *)GifFile->Private);
+	free(GifFile);
+        return GIF_ERROR;
+    }
+
+    if (Private->File && (fclose(Private->File) != 0)) {
+	if (ErrorCode != NULL)
+	    *ErrorCode = D_GIF_ERR_CLOSE_FAILED;
+	free((char *)GifFile->Private);
+	free(GifFile);
+        return GIF_ERROR;
+    }
+
+    free((char *)GifFile->Private);
+    free(GifFile);
+    if (ErrorCode != NULL)
+	*ErrorCode = D_GIF_SUCCEEDED;
+    return GIF_OK;
+}
+
+/******************************************************************************
+ Get 2 bytes (word) from the given file:
+******************************************************************************/
+static int
+DGifGetWord(GifFileType *GifFile, GifWord *Word)
+{
+    unsigned char c[2];
+
+    /* coverity[check_return] */
+    if (READ(GifFile, c, 2) != 2) {
+        GifFile->Error = D_GIF_ERR_READ_FAILED;
+        return GIF_ERROR;
+    }
+
+    *Word = (GifWord)UNSIGNED_LITTLE_ENDIAN(c[0], c[1]);
+    return GIF_OK;
+}
+
+/******************************************************************************
+ Get the image code in compressed form.  This routine can be called if the
+ information needed to be piped out as is. Obviously this is much faster
+ than decoding and encoding again. This routine should be followed by calls
+ to DGifGetCodeNext, until NULL block is returned.
+ The block should NOT be freed by the user (not dynamically allocated).
+******************************************************************************/
+int
+DGifGetCode(GifFileType *GifFile, int *CodeSize, GifByteType **CodeBlock)
+{
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    if (!IS_READABLE(Private)) {
+        /* This file was NOT open for reading: */
+        GifFile->Error = D_GIF_ERR_NOT_READABLE;
+        return GIF_ERROR;
+    }
+
+    *CodeSize = Private->BitsPerPixel;
+
+    return DGifGetCodeNext(GifFile, CodeBlock);
+}
+
+/******************************************************************************
+ Continue to get the image code in compressed form. This routine should be
+ called until NULL block is returned.
+ The block should NOT be freed by the user (not dynamically allocated).
+******************************************************************************/
+int
+DGifGetCodeNext(GifFileType *GifFile, GifByteType **CodeBlock)
+{
+    GifByteType Buf;
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    /* coverity[tainted_data_argument] */
+    /* coverity[check_return] */
+    if (READ(GifFile, &Buf, 1) != 1) {
+        GifFile->Error = D_GIF_ERR_READ_FAILED;
+        return GIF_ERROR;
+    }
+
+    /* coverity[lower_bounds] */
+    if (Buf > 0) {
+        *CodeBlock = Private->Buf;    /* Use private unused buffer. */
+        (*CodeBlock)[0] = Buf;  /* Pascal strings notation (pos. 0 is len.). */
+	/* coverity[tainted_data] */
+        if (READ(GifFile, &((*CodeBlock)[1]), Buf) != Buf) {
+            GifFile->Error = D_GIF_ERR_READ_FAILED;
+            return GIF_ERROR;
+        }
+    } else {
+        *CodeBlock = NULL;
+        Private->Buf[0] = 0;    /* Make sure the buffer is empty! */
+        Private->PixelCount = 0;    /* And local info. indicate image read. */
+    }
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ Setup the LZ decompression for this image:
+******************************************************************************/
+static int
+DGifSetupDecompress(GifFileType *GifFile)
+{
+    int i, BitsPerPixel;
+    GifByteType CodeSize;
+    GifPrefixType *Prefix;
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    /* coverity[check_return] */
+    if (READ(GifFile, &CodeSize, 1) < 1) {    /* Read Code size from file. */
+	return GIF_ERROR;    /* Failed to read Code size. */
+    }
+    BitsPerPixel = CodeSize;
+
+    /* this can only happen on a severely malformed GIF */
+    if (BitsPerPixel > 8) {
+	GifFile->Error = D_GIF_ERR_READ_FAILED;	/* somewhat bogus error code */
+	return GIF_ERROR;    /* Failed to read Code size. */
+    }
+
+    Private->Buf[0] = 0;    /* Input Buffer empty. */
+    Private->BitsPerPixel = BitsPerPixel;
+    Private->ClearCode = (1 << BitsPerPixel);
+    Private->EOFCode = Private->ClearCode + 1;
+    Private->RunningCode = Private->EOFCode + 1;
+    Private->RunningBits = BitsPerPixel + 1;    /* Number of bits per code. */
+    Private->MaxCode1 = 1 << Private->RunningBits;    /* Max. code + 1. */
+    Private->StackPtr = 0;    /* No pixels on the pixel stack. */
+    Private->LastCode = NO_SUCH_CODE;
+    Private->CrntShiftState = 0;    /* No information in CrntShiftDWord. */
+    Private->CrntShiftDWord = 0;
+
+    Prefix = Private->Prefix;
+    for (i = 0; i <= LZ_MAX_CODE; i++)
+        Prefix[i] = NO_SUCH_CODE;
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ The LZ decompression routine:
+ This version decompress the given GIF file into Line of length LineLen.
+ This routine can be called few times (one per scan line, for example), in
+ order the complete the whole image.
+******************************************************************************/
+static int
+DGifDecompressLine(GifFileType *GifFile, GifPixelType *Line, int LineLen)
+{
+    int i = 0;
+    int j, CrntCode, EOFCode, ClearCode, CrntPrefix, LastCode, StackPtr;
+    GifByteType *Stack, *Suffix;
+    GifPrefixType *Prefix;
+    GifFilePrivateType *Private = (GifFilePrivateType *) GifFile->Private;
+
+    StackPtr = Private->StackPtr;
+    Prefix = Private->Prefix;
+    Suffix = Private->Suffix;
+    Stack = Private->Stack;
+    EOFCode = Private->EOFCode;
+    ClearCode = Private->ClearCode;
+    LastCode = Private->LastCode;
+
+    if (StackPtr > LZ_MAX_CODE) {
+        return GIF_ERROR;
+    }
+
+    if (StackPtr != 0) {
+        /* Let pop the stack off before continueing to read the GIF file: */
+        while (StackPtr != 0 && i < LineLen)
+            Line[i++] = Stack[--StackPtr];
+    }
+
+    while (i < LineLen) {    /* Decode LineLen items. */
+        if (DGifDecompressInput(GifFile, &CrntCode) == GIF_ERROR)
+            return GIF_ERROR;
+
+        if (CrntCode == EOFCode) {
+            /* Note however that usually we will not be here as we will stop
+             * decoding as soon as we got all the pixel, or EOF code will
+             * not be read at all, and DGifGetLine/Pixel clean everything.  */
+	    GifFile->Error = D_GIF_ERR_EOF_TOO_SOON;
+	    return GIF_ERROR;
+        } else if (CrntCode == ClearCode) {
+            /* We need to start over again: */
+            for (j = 0; j <= LZ_MAX_CODE; j++)
+                Prefix[j] = NO_SUCH_CODE;
+            Private->RunningCode = Private->EOFCode + 1;
+            Private->RunningBits = Private->BitsPerPixel + 1;
+            Private->MaxCode1 = 1 << Private->RunningBits;
+            LastCode = Private->LastCode = NO_SUCH_CODE;
+        } else {
+            /* Its regular code - if in pixel range simply add it to output
+             * stream, otherwise trace to codes linked list until the prefix
+             * is in pixel range: */
+            if (CrntCode < ClearCode) {
+                /* This is simple - its pixel scalar, so add it to output: */
+                Line[i++] = CrntCode;
+            } else {
+                /* Its a code to needed to be traced: trace the linked list
+                 * until the prefix is a pixel, while pushing the suffix
+                 * pixels on our stack. If we done, pop the stack in reverse
+                 * (thats what stack is good for!) order to output.  */
+                if (Prefix[CrntCode] == NO_SUCH_CODE) {
+                    CrntPrefix = LastCode;
+
+                    /* Only allowed if CrntCode is exactly the running code:
+                     * In that case CrntCode = XXXCode, CrntCode or the
+                     * prefix code is last code and the suffix char is
+                     * exactly the prefix of last code! */
+                    if (CrntCode == Private->RunningCode - 2) {
+                        Suffix[Private->RunningCode - 2] =
+                           Stack[StackPtr++] = DGifGetPrefixChar(Prefix,
+                                                                 LastCode,
+                                                                 ClearCode);
+                    } else {
+                        Suffix[Private->RunningCode - 2] =
+                           Stack[StackPtr++] = DGifGetPrefixChar(Prefix,
+                                                                 CrntCode,
+                                                                 ClearCode);
+                    }
+                } else
+                    CrntPrefix = CrntCode;
+
+                /* Now (if image is O.K.) we should not get a NO_SUCH_CODE
+                 * during the trace. As we might loop forever, in case of
+                 * defective image, we use StackPtr as loop counter and stop
+                 * before overflowing Stack[]. */
+                while (StackPtr < LZ_MAX_CODE &&
+                       CrntPrefix > ClearCode && CrntPrefix <= LZ_MAX_CODE) {
+                    Stack[StackPtr++] = Suffix[CrntPrefix];
+                    CrntPrefix = Prefix[CrntPrefix];
+                }
+                if (StackPtr >= LZ_MAX_CODE || CrntPrefix > LZ_MAX_CODE) {
+                    GifFile->Error = D_GIF_ERR_IMAGE_DEFECT;
+                    return GIF_ERROR;
+                }
+                /* Push the last character on stack: */
+                Stack[StackPtr++] = CrntPrefix;
+
+                /* Now lets pop all the stack into output: */
+                while (StackPtr != 0 && i < LineLen)
+                    Line[i++] = Stack[--StackPtr];
+            }
+            if (LastCode != NO_SUCH_CODE && Prefix[Private->RunningCode - 2] == NO_SUCH_CODE) {
+                Prefix[Private->RunningCode - 2] = LastCode;
+
+                if (CrntCode == Private->RunningCode - 2) {
+                    /* Only allowed if CrntCode is exactly the running code:
+                     * In that case CrntCode = XXXCode, CrntCode or the
+                     * prefix code is last code and the suffix char is
+                     * exactly the prefix of last code! */
+                    Suffix[Private->RunningCode - 2] =
+                       DGifGetPrefixChar(Prefix, LastCode, ClearCode);
+                } else {
+                    Suffix[Private->RunningCode - 2] =
+                       DGifGetPrefixChar(Prefix, CrntCode, ClearCode);
+                }
+            }
+            LastCode = CrntCode;
+        }
+    }
+
+    Private->LastCode = LastCode;
+    Private->StackPtr = StackPtr;
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ Routine to trace the Prefixes linked list until we get a prefix which is
+ not code, but a pixel value (less than ClearCode). Returns that pixel value.
+ If image is defective, we might loop here forever, so we limit the loops to
+ the maximum possible if image O.k. - LZ_MAX_CODE times.
+******************************************************************************/
+static int
+DGifGetPrefixChar(GifPrefixType *Prefix, int Code, int ClearCode)
+{
+    int i = 0;
+
+    while (Code > ClearCode && i++ <= LZ_MAX_CODE) {
+        if (Code > LZ_MAX_CODE) {
+            return NO_SUCH_CODE;
+        }
+        Code = Prefix[Code];
+    }
+    return Code;
+}
+
+/******************************************************************************
+ Interface for accessing the LZ codes directly. Set Code to the real code
+ (12bits), or to -1 if EOF code is returned.
+******************************************************************************/
+int
+DGifGetLZCodes(GifFileType *GifFile, int *Code)
+{
+    GifByteType *CodeBlock;
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    if (!IS_READABLE(Private)) {
+        /* This file was NOT open for reading: */
+        GifFile->Error = D_GIF_ERR_NOT_READABLE;
+        return GIF_ERROR;
+    }
+
+    if (DGifDecompressInput(GifFile, Code) == GIF_ERROR)
+        return GIF_ERROR;
+
+    if (*Code == Private->EOFCode) {
+        /* Skip rest of codes (hopefully only NULL terminating block): */
+        do {
+            if (DGifGetCodeNext(GifFile, &CodeBlock) == GIF_ERROR)
+                return GIF_ERROR;
+        } while (CodeBlock != NULL) ;
+
+        *Code = -1;
+    } else if (*Code == Private->ClearCode) {
+        /* We need to start over again: */
+        Private->RunningCode = Private->EOFCode + 1;
+        Private->RunningBits = Private->BitsPerPixel + 1;
+        Private->MaxCode1 = 1 << Private->RunningBits;
+    }
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ The LZ decompression input routine:
+ This routine is responsable for the decompression of the bit stream from
+ 8 bits (bytes) packets, into the real codes.
+ Returns GIF_OK if read successfully.
+******************************************************************************/
+static int
+DGifDecompressInput(GifFileType *GifFile, int *Code)
+{
+    static const unsigned short CodeMasks[] = {
+	0x0000, 0x0001, 0x0003, 0x0007,
+	0x000f, 0x001f, 0x003f, 0x007f,
+	0x00ff, 0x01ff, 0x03ff, 0x07ff,
+	0x0fff
+    };
+
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    GifByteType NextByte;
+
+    /* The image can't contain more than LZ_BITS per code. */
+    if (Private->RunningBits > LZ_BITS) {
+        GifFile->Error = D_GIF_ERR_IMAGE_DEFECT;
+        return GIF_ERROR;
+    }
+    
+    while (Private->CrntShiftState < Private->RunningBits) {
+        /* Needs to get more bytes from input stream for next code: */
+        if (DGifBufferedInput(GifFile, Private->Buf, &NextByte) == GIF_ERROR) {
+            return GIF_ERROR;
+        }
+        Private->CrntShiftDWord |=
+	    ((unsigned long)NextByte) << Private->CrntShiftState;
+        Private->CrntShiftState += 8;
+    }
+    *Code = Private->CrntShiftDWord & CodeMasks[Private->RunningBits];
+
+    Private->CrntShiftDWord >>= Private->RunningBits;
+    Private->CrntShiftState -= Private->RunningBits;
+
+    /* If code cannot fit into RunningBits bits, must raise its size. Note
+     * however that codes above 4095 are used for special signaling.
+     * If we're using LZ_BITS bits already and we're at the max code, just
+     * keep using the table as it is, don't increment Private->RunningCode.
+     */
+    if (Private->RunningCode < LZ_MAX_CODE + 2 &&
+	++Private->RunningCode > Private->MaxCode1 &&
+	Private->RunningBits < LZ_BITS) {
+        Private->MaxCode1 <<= 1;
+        Private->RunningBits++;
+    }
+    return GIF_OK;
+}
+
+/******************************************************************************
+ This routines read one GIF data block at a time and buffers it internally
+ so that the decompression routine could access it.
+ The routine returns the next byte from its internal buffer (or read next
+ block in if buffer empty) and returns GIF_OK if succesful.
+******************************************************************************/
+static int
+DGifBufferedInput(GifFileType *GifFile, GifByteType *Buf, GifByteType *NextByte)
+{
+    if (Buf[0] == 0) {
+        /* Needs to read the next buffer - this one is empty: */
+	/* coverity[check_return] */
+        if (READ(GifFile, Buf, 1) != 1) {
+            GifFile->Error = D_GIF_ERR_READ_FAILED;
+            return GIF_ERROR;
+        }
+        /* There shouldn't be any empty data blocks here as the LZW spec
+         * says the LZW termination code should come first.  Therefore we
+         * shouldn't be inside this routine at that point.
+         */
+        if (Buf[0] == 0) {
+            GifFile->Error = D_GIF_ERR_IMAGE_DEFECT;
+            return GIF_ERROR;
+        }
+        if (READ(GifFile, &Buf[1], Buf[0]) != Buf[0]) {
+            GifFile->Error = D_GIF_ERR_READ_FAILED;
+            return GIF_ERROR;
+        }
+        *NextByte = Buf[1];
+        Buf[1] = 2;    /* We use now the second place as last char read! */
+        Buf[0]--;
+    } else {
+        *NextByte = Buf[Buf[1]++];
+        Buf[0]--;
+    }
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ This routine reads an entire GIF into core, hanging all its state info off
+ the GifFileType pointer.  Call DGifOpenFileName() or DGifOpenFileHandle()
+ first to initialize I/O.  Its inverse is EGifSpew().
+*******************************************************************************/
+int
+DGifSlurp(GifFileType *GifFile)
+{
+    size_t ImageSize;
+    GifRecordType RecordType;
+    SavedImage *sp;
+    GifByteType *ExtData;
+    int ExtFunction;
+
+    GifFile->ExtensionBlocks = NULL;
+    GifFile->ExtensionBlockCount = 0;
+
+    do {
+        if (DGifGetRecordType(GifFile, &RecordType) == GIF_ERROR)
+            return (GIF_ERROR);
+
+        switch (RecordType) {
+          case IMAGE_DESC_RECORD_TYPE:
+              if (DGifGetImageDesc(GifFile) == GIF_ERROR)
+                  return (GIF_ERROR);
+
+              sp = &GifFile->SavedImages[GifFile->ImageCount - 1];
+              /* Allocate memory for the image */
+              if (sp->ImageDesc.Width < 0 && sp->ImageDesc.Height < 0 &&
+                      sp->ImageDesc.Width > (INT_MAX / sp->ImageDesc.Height)) {
+                  return GIF_ERROR;
+              }
+              ImageSize = sp->ImageDesc.Width * sp->ImageDesc.Height;
+
+              if (ImageSize > (SIZE_MAX / sizeof(GifPixelType))) {
+                  return GIF_ERROR;
+              }
+              sp->RasterBits = (unsigned char *)reallocarray(NULL, ImageSize,
+                      sizeof(GifPixelType));
+
+              if (sp->RasterBits == NULL) {
+                  return GIF_ERROR;
+              }
+
+	      if (sp->ImageDesc.Interlace) {
+		  int i, j;
+		   /* 
+		    * The way an interlaced image should be read - 
+		    * offsets and jumps...
+		    */
+		  int InterlacedOffset[] = { 0, 4, 2, 1 };
+		  int InterlacedJumps[] = { 8, 8, 4, 2 };
+		  /* Need to perform 4 passes on the image */
+		  for (i = 0; i < 4; i++)
+		      for (j = InterlacedOffset[i]; 
+			   j < sp->ImageDesc.Height;
+			   j += InterlacedJumps[i]) {
+			  if (DGifGetLine(GifFile, 
+					  sp->RasterBits+j*sp->ImageDesc.Width, 
+					  sp->ImageDesc.Width) == GIF_ERROR)
+			      return GIF_ERROR;
+		      }
+	      }
+	      else {
+		  if (DGifGetLine(GifFile,sp->RasterBits,ImageSize)==GIF_ERROR)
+		      return (GIF_ERROR);
+	      }
+
+              if (GifFile->ExtensionBlocks) {
+                  sp->ExtensionBlocks = GifFile->ExtensionBlocks;
+                  sp->ExtensionBlockCount = GifFile->ExtensionBlockCount;
+
+                  GifFile->ExtensionBlocks = NULL;
+                  GifFile->ExtensionBlockCount = 0;
+              }
+              break;
+
+          case EXTENSION_RECORD_TYPE:
+              if (DGifGetExtension(GifFile,&ExtFunction,&ExtData) == GIF_ERROR)
+                  return (GIF_ERROR);
+	      /* Create an extension block with our data */
+              if (ExtData != NULL) {
+		  if (GifAddExtensionBlock(&GifFile->ExtensionBlockCount,
+					   &GifFile->ExtensionBlocks, 
+					   ExtFunction, ExtData[0], &ExtData[1])
+		      == GIF_ERROR)
+		      return (GIF_ERROR);
+	      }
+              while (ExtData != NULL) {
+                  if (DGifGetExtensionNext(GifFile, &ExtData) == GIF_ERROR)
+                      return (GIF_ERROR);
+                  /* Continue the extension block */
+		  if (ExtData != NULL)
+		      if (GifAddExtensionBlock(&GifFile->ExtensionBlockCount,
+					       &GifFile->ExtensionBlocks,
+					       CONTINUE_EXT_FUNC_CODE, 
+					       ExtData[0], &ExtData[1]) == GIF_ERROR)
+                      return (GIF_ERROR);
+              }
+              break;
+
+          case TERMINATE_RECORD_TYPE:
+              break;
+
+          default:    /* Should be trapped by DGifGetRecordType */
+              break;
+        }
+    } while (RecordType != TERMINATE_RECORD_TYPE);
+
+    /* Sanity check for corrupted file */
+    if (GifFile->ImageCount == 0) {
+	GifFile->Error = D_GIF_ERR_NO_IMAG_DSCR;
+	return(GIF_ERROR);
+    }
+
+    return (GIF_OK);
+}
+
+/* end */
diff --git a/Src/external_dependencies/giflib/egif_lib.c b/Src/external_dependencies/giflib/egif_lib.c
new file mode 100644
index 00000000..8de31d3c
--- /dev/null
+++ b/Src/external_dependencies/giflib/egif_lib.c
@@ -0,0 +1,1154 @@
+/******************************************************************************
+
+egif_lib.c - GIF encoding
+
+The functions here and in dgif_lib.c are partitioned carefully so that
+if you only require one of read and write capability, only one of these
+two modules will be linked.  Preserve this property!
+
+*****************************************************************************/
+
+//#include <unistd.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <fcntl.h>
+
+#ifdef _WIN32
+#include <io.h>
+#else
+#include <sys/types.h>
+#endif /* _WIN32 */
+#include <sys/stat.h>
+
+#include "gif_lib.h"
+#include "gif_lib_private.h"
+
+/* Masks given codes to BitsPerPixel, to make sure all codes are in range: */
+/*@+charint@*/
+static const GifPixelType CodeMask[] = {
+    0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff
+};
+/*@-charint@*/
+
+static int EGifPutWord(int Word, GifFileType * GifFile);
+static int EGifSetupCompress(GifFileType * GifFile);
+static int EGifCompressLine(GifFileType * GifFile, GifPixelType * Line,
+                            int LineLen);
+static int EGifCompressOutput(GifFileType * GifFile, int Code);
+static int EGifBufferedOutput(GifFileType * GifFile, GifByteType * Buf,
+                              int c);
+
+/* extract bytes from an unsigned word */
+#define LOBYTE(x)	((x) & 0xff)
+#define HIBYTE(x)	(((x) >> 8) & 0xff)
+
+/******************************************************************************
+ Open a new GIF file for write, specified by name. If TestExistance then
+ if the file exists this routines fails (returns NULL).
+ Returns a dynamically allocated GifFileType pointer which serves as the GIF
+ info record. The Error member is cleared if successful.
+******************************************************************************/
+GifFileType *
+EGifOpenFileName(const char *FileName, const bool TestExistence, int *Error)
+{
+
+    int FileHandle;
+    GifFileType *GifFile;
+
+    if (TestExistence)
+        FileHandle = open(FileName, O_WRONLY | O_CREAT | O_EXCL, 
+			  S_IREAD | S_IWRITE);
+    else
+        FileHandle = open(FileName, O_WRONLY | O_CREAT | O_TRUNC, 
+			  S_IREAD | S_IWRITE);
+
+    if (FileHandle == -1) {
+        if (Error != NULL)
+	    *Error = E_GIF_ERR_OPEN_FAILED;
+        return NULL;
+    }
+    GifFile = EGifOpenFileHandle(FileHandle, Error);
+    if (GifFile == (GifFileType *) NULL)
+        (void)close(FileHandle);
+    return GifFile;
+}
+
+/******************************************************************************
+ Update a new GIF file, given its file handle, which must be opened for
+ write in binary mode.
+ Returns dynamically allocated a GifFileType pointer which serves as the GIF
+ info record.
+ Only fails on a memory allocation error.
+******************************************************************************/
+GifFileType *
+EGifOpenFileHandle(const int FileHandle, int *Error)
+{
+    GifFileType *GifFile;
+    GifFilePrivateType *Private;
+    FILE *f;
+
+    GifFile = (GifFileType *) malloc(sizeof(GifFileType));
+    if (GifFile == NULL) {
+        return NULL;
+    }
+
+    memset(GifFile, '\0', sizeof(GifFileType));
+
+    Private = (GifFilePrivateType *)malloc(sizeof(GifFilePrivateType));
+    if (Private == NULL) {
+        free(GifFile);
+        if (Error != NULL)
+	    *Error = E_GIF_ERR_NOT_ENOUGH_MEM;
+        return NULL;
+    }
+    /*@i1@*/memset(Private, '\0', sizeof(GifFilePrivateType));
+    if ((Private->HashTable = _InitHashTable()) == NULL) {
+        free(GifFile);
+        free(Private);
+        if (Error != NULL)
+	    *Error = E_GIF_ERR_NOT_ENOUGH_MEM;
+        return NULL;
+    }
+
+#ifdef _WIN32
+    _setmode(FileHandle, O_BINARY);    /* Make sure it is in binary mode. */
+#endif /* _WIN32 */
+
+    f = fdopen(FileHandle, "wb");    /* Make it into a stream: */
+
+    GifFile->Private = (void *)Private;
+    Private->FileHandle = FileHandle;
+    Private->File = f;
+    Private->FileState = FILE_STATE_WRITE;
+    Private->gif89 = false;
+
+    Private->Write = (OutputFunc) 0;    /* No user write routine (MRB) */
+    GifFile->UserData = (void *)NULL;    /* No user write handle (MRB) */
+
+    GifFile->Error = 0;
+
+    return GifFile;
+}
+
+/******************************************************************************
+ Output constructor that takes user supplied output function.
+ Basically just a copy of EGifOpenFileHandle. (MRB)
+******************************************************************************/
+GifFileType *
+EGifOpen(void *userData, OutputFunc writeFunc, int *Error)
+{
+    GifFileType *GifFile;
+    GifFilePrivateType *Private;
+
+    GifFile = (GifFileType *)malloc(sizeof(GifFileType));
+    if (GifFile == NULL) {
+        if (Error != NULL)
+	    *Error = E_GIF_ERR_NOT_ENOUGH_MEM;
+        return NULL;
+    }
+
+    memset(GifFile, '\0', sizeof(GifFileType));
+
+    Private = (GifFilePrivateType *)malloc(sizeof(GifFilePrivateType));
+    if (Private == NULL) {
+        free(GifFile);
+        if (Error != NULL)
+	    *Error = E_GIF_ERR_NOT_ENOUGH_MEM;
+        return NULL;
+    }
+
+    memset(Private, '\0', sizeof(GifFilePrivateType));
+
+    Private->HashTable = _InitHashTable();
+    if (Private->HashTable == NULL) {
+        free (GifFile);
+        free (Private);
+        if (Error != NULL)
+	    *Error = E_GIF_ERR_NOT_ENOUGH_MEM;
+        return NULL;
+    }
+
+    GifFile->Private = (void *)Private;
+    Private->FileHandle = 0;
+    Private->File = (FILE *) 0;
+    Private->FileState = FILE_STATE_WRITE;
+
+    Private->Write = writeFunc;    /* User write routine (MRB) */
+    GifFile->UserData = userData;    /* User write handle (MRB) */
+
+    Private->gif89 = false;	/* initially, write GIF87 */
+
+    GifFile->Error = 0;
+
+    return GifFile;
+}
+
+/******************************************************************************
+ Routine to compute the GIF version that will be written on output.
+******************************************************************************/
+const char *
+EGifGetGifVersion(GifFileType *GifFile)
+{
+    GifFilePrivateType *Private = (GifFilePrivateType *) GifFile->Private;
+    int i, j;
+
+    /* 
+     * Bulletproofing - always write GIF89 if we need to.
+     * Note, we don't clear the gif89 flag here because
+     * users of the sequential API might have called EGifSetGifVersion()
+     * in order to set that flag.
+     */
+    for (i = 0; i < GifFile->ImageCount; i++) {
+        for (j = 0; j < GifFile->SavedImages[i].ExtensionBlockCount; j++) {
+            int function =
+               GifFile->SavedImages[i].ExtensionBlocks[j].Function;
+
+            if (function == COMMENT_EXT_FUNC_CODE
+                || function == GRAPHICS_EXT_FUNC_CODE
+                || function == PLAINTEXT_EXT_FUNC_CODE
+                || function == APPLICATION_EXT_FUNC_CODE)
+                Private->gif89 = true;
+        }
+    }
+    for (i = 0; i < GifFile->ExtensionBlockCount; i++) {
+	int function = GifFile->ExtensionBlocks[i].Function;
+
+	if (function == COMMENT_EXT_FUNC_CODE
+	    || function == GRAPHICS_EXT_FUNC_CODE
+	    || function == PLAINTEXT_EXT_FUNC_CODE
+	    || function == APPLICATION_EXT_FUNC_CODE)
+	    Private->gif89 = true;
+    }
+ 
+    if (Private->gif89)
+	return GIF89_STAMP;
+    else
+	return GIF87_STAMP;
+}
+
+/******************************************************************************
+ Set the GIF version. In the extremely unlikely event that there is ever
+ another version, replace the bool argument with an enum in which the 
+ GIF87 value is 0 (numerically the same as bool false) and the GIF89 value
+ is 1 (numerically the same as bool true).  That way we'll even preserve
+ object-file compatibility!
+******************************************************************************/
+void EGifSetGifVersion(GifFileType *GifFile, const bool gif89)
+{
+    GifFilePrivateType *Private = (GifFilePrivateType *) GifFile->Private;
+
+    Private->gif89 = gif89;
+}
+
+/******************************************************************************
+ All writes to the GIF should go through this.
+******************************************************************************/
+static int InternalWrite(GifFileType *GifFileOut, 
+		   const unsigned char *buf, size_t len)
+{
+    GifFilePrivateType *Private = (GifFilePrivateType*)GifFileOut->Private;
+    if (Private->Write)
+	return Private->Write(GifFileOut,buf,len);
+    else
+	return fwrite(buf, 1, len, Private->File);
+}
+
+/******************************************************************************
+ This routine should be called before any other EGif calls, immediately
+ following the GIF file opening.
+******************************************************************************/
+int
+EGifPutScreenDesc(GifFileType *GifFile,
+                  const int Width,
+                  const int Height,
+                  const int ColorRes,
+                  const int BackGround,
+                  const ColorMapObject *ColorMap)
+{
+    GifByteType Buf[3];
+    GifFilePrivateType *Private = (GifFilePrivateType *) GifFile->Private;
+    const char *write_version;
+
+    if (Private->FileState & FILE_STATE_SCREEN) {
+        /* If already has screen descriptor - something is wrong! */
+        GifFile->Error = E_GIF_ERR_HAS_SCRN_DSCR;
+        return GIF_ERROR;
+    }
+    if (!IS_WRITEABLE(Private)) {
+        /* This file was NOT open for writing: */
+        GifFile->Error = E_GIF_ERR_NOT_WRITEABLE;
+        return GIF_ERROR;
+    }
+
+    write_version = EGifGetGifVersion(GifFile);
+
+    /* First write the version prefix into the file. */
+    if (InternalWrite(GifFile, (unsigned char *)write_version,
+              strlen(write_version)) != strlen(write_version)) {
+        GifFile->Error = E_GIF_ERR_WRITE_FAILED;
+        return GIF_ERROR;
+    }
+
+    GifFile->SWidth = Width;
+    GifFile->SHeight = Height;
+    GifFile->SColorResolution = ColorRes;
+    GifFile->SBackGroundColor = BackGround;
+    if (ColorMap) {
+        GifFile->SColorMap = GifMakeMapObject(ColorMap->ColorCount,
+                                           ColorMap->Colors);
+        if (GifFile->SColorMap == NULL) {
+            GifFile->Error = E_GIF_ERR_NOT_ENOUGH_MEM;
+            return GIF_ERROR;
+        }
+    } else
+        GifFile->SColorMap = NULL;
+
+    /*
+     * Put the logical screen descriptor into the file:
+     */
+    /* Logical Screen Descriptor: Dimensions */
+    (void)EGifPutWord(Width, GifFile);
+    (void)EGifPutWord(Height, GifFile);
+
+    /* Logical Screen Descriptor: Packed Fields */
+    /* Note: We have actual size of the color table default to the largest
+     * possible size (7+1 == 8 bits) because the decoder can use it to decide
+     * how to display the files.
+     */
+    Buf[0] = (ColorMap ? 0x80 : 0x00) | /* Yes/no global colormap */
+             ((ColorRes - 1) << 4) | /* Bits allocated to each primary color */
+        (ColorMap ? ColorMap->BitsPerPixel - 1 : 0x07 ); /* Actual size of the
+                                                            color table. */
+    if (ColorMap != NULL && ColorMap->SortFlag)
+	Buf[0] |= 0x08;
+    Buf[1] = BackGround;    /* Index into the ColorTable for background color */
+    Buf[2] = GifFile->AspectByte;     /* Pixel Aspect Ratio */
+    InternalWrite(GifFile, Buf, 3);
+
+    /* If we have Global color map - dump it also: */
+    if (ColorMap != NULL) {
+	int i;
+        for (i = 0; i < ColorMap->ColorCount; i++) {
+            /* Put the ColorMap out also: */
+            Buf[0] = ColorMap->Colors[i].Red;
+            Buf[1] = ColorMap->Colors[i].Green;
+            Buf[2] = ColorMap->Colors[i].Blue;
+            if (InternalWrite(GifFile, Buf, 3) != 3) {
+                GifFile->Error = E_GIF_ERR_WRITE_FAILED;
+                return GIF_ERROR;
+            }
+        }
+    }
+
+    /* Mark this file as has screen descriptor, and no pixel written yet: */
+    Private->FileState |= FILE_STATE_SCREEN;
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ This routine should be called before any attempt to dump an image - any
+ call to any of the pixel dump routines.
+******************************************************************************/
+int
+EGifPutImageDesc(GifFileType *GifFile,
+                 const int Left,
+                 const int Top,
+                 const int Width,
+                 const int Height,
+                 const bool Interlace,
+                 const ColorMapObject *ColorMap)
+{
+    GifByteType Buf[3];
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    if (Private->FileState & FILE_STATE_IMAGE &&
+        Private->PixelCount > 0xffff0000UL) {
+        /* If already has active image descriptor - something is wrong! */
+        GifFile->Error = E_GIF_ERR_HAS_IMAG_DSCR;
+        return GIF_ERROR;
+    }
+    if (!IS_WRITEABLE(Private)) {
+        /* This file was NOT open for writing: */
+        GifFile->Error = E_GIF_ERR_NOT_WRITEABLE;
+        return GIF_ERROR;
+    }
+    GifFile->Image.Left = Left;
+    GifFile->Image.Top = Top;
+    GifFile->Image.Width = Width;
+    GifFile->Image.Height = Height;
+    GifFile->Image.Interlace = Interlace;
+    if (ColorMap) {
+	if (GifFile->Image.ColorMap != NULL) {
+	    GifFreeMapObject(GifFile->Image.ColorMap);
+	    GifFile->Image.ColorMap = NULL;
+	}
+        GifFile->Image.ColorMap = GifMakeMapObject(ColorMap->ColorCount,
+                                                ColorMap->Colors);
+        if (GifFile->Image.ColorMap == NULL) {
+            GifFile->Error = E_GIF_ERR_NOT_ENOUGH_MEM;
+            return GIF_ERROR;
+        }
+    } else {
+        GifFile->Image.ColorMap = NULL;
+    }
+
+    /* Put the image descriptor into the file: */
+    Buf[0] = DESCRIPTOR_INTRODUCER;    /* Image separator character. */
+    InternalWrite(GifFile, Buf, 1);
+    (void)EGifPutWord(Left, GifFile);
+    (void)EGifPutWord(Top, GifFile);
+    (void)EGifPutWord(Width, GifFile);
+    (void)EGifPutWord(Height, GifFile);
+    Buf[0] = (ColorMap ? 0x80 : 0x00) |
+       (Interlace ? 0x40 : 0x00) |
+       (ColorMap ? ColorMap->BitsPerPixel - 1 : 0);
+    InternalWrite(GifFile, Buf, 1);
+
+    /* If we have Global color map - dump it also: */
+    if (ColorMap != NULL) {
+	int i;
+        for (i = 0; i < ColorMap->ColorCount; i++) {
+            /* Put the ColorMap out also: */
+            Buf[0] = ColorMap->Colors[i].Red;
+            Buf[1] = ColorMap->Colors[i].Green;
+            Buf[2] = ColorMap->Colors[i].Blue;
+            if (InternalWrite(GifFile, Buf, 3) != 3) {
+                GifFile->Error = E_GIF_ERR_WRITE_FAILED;
+                return GIF_ERROR;
+            }
+        }
+    }
+    if (GifFile->SColorMap == NULL && GifFile->Image.ColorMap == NULL) {
+        GifFile->Error = E_GIF_ERR_NO_COLOR_MAP;
+        return GIF_ERROR;
+    }
+
+    /* Mark this file as has screen descriptor: */
+    Private->FileState |= FILE_STATE_IMAGE;
+    Private->PixelCount = (long)Width *(long)Height;
+
+    /* Reset compress algorithm parameters. */
+    (void)EGifSetupCompress(GifFile);
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ Put one full scanned line (Line) of length LineLen into GIF file.
+******************************************************************************/
+int
+EGifPutLine(GifFileType * GifFile, GifPixelType *Line, int LineLen)
+{
+    int i;
+    GifPixelType Mask;
+    GifFilePrivateType *Private = (GifFilePrivateType *) GifFile->Private;
+
+    if (!IS_WRITEABLE(Private)) {
+        /* This file was NOT open for writing: */
+        GifFile->Error = E_GIF_ERR_NOT_WRITEABLE;
+        return GIF_ERROR;
+    }
+
+    if (!LineLen)
+        LineLen = GifFile->Image.Width;
+    if (Private->PixelCount < (unsigned)LineLen) {
+        GifFile->Error = E_GIF_ERR_DATA_TOO_BIG;
+        return GIF_ERROR;
+    }
+    Private->PixelCount -= LineLen;
+
+    /* Make sure the codes are not out of bit range, as we might generate
+     * wrong code (because of overflow when we combine them) in this case: */
+    Mask = CodeMask[Private->BitsPerPixel];
+    for (i = 0; i < LineLen; i++)
+        Line[i] &= Mask;
+
+    return EGifCompressLine(GifFile, Line, LineLen);
+}
+
+/******************************************************************************
+ Put one pixel (Pixel) into GIF file.
+******************************************************************************/
+int
+EGifPutPixel(GifFileType *GifFile, GifPixelType Pixel)
+{
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    if (!IS_WRITEABLE(Private)) {
+        /* This file was NOT open for writing: */
+        GifFile->Error = E_GIF_ERR_NOT_WRITEABLE;
+        return GIF_ERROR;
+    }
+
+    if (Private->PixelCount == 0) {
+        GifFile->Error = E_GIF_ERR_DATA_TOO_BIG;
+        return GIF_ERROR;
+    }
+    --Private->PixelCount;
+
+    /* Make sure the code is not out of bit range, as we might generate
+     * wrong code (because of overflow when we combine them) in this case: */
+    Pixel &= CodeMask[Private->BitsPerPixel];
+
+    return EGifCompressLine(GifFile, &Pixel, 1);
+}
+
+/******************************************************************************
+ Put a comment into GIF file using the GIF89 comment extension block.
+******************************************************************************/
+int
+EGifPutComment(GifFileType *GifFile, const char *Comment)
+{
+    unsigned int length;
+    char *buf;
+
+    length = strlen(Comment);
+    if (length <= 255) {
+        return EGifPutExtension(GifFile, COMMENT_EXT_FUNC_CODE,
+                                length, Comment);
+    } else {
+        buf = (char *)Comment;
+        if (EGifPutExtensionLeader(GifFile, COMMENT_EXT_FUNC_CODE)
+                == GIF_ERROR) {
+            return GIF_ERROR;
+        }
+
+        /* Break the comment into 255 byte sub blocks */
+        while (length > 255) {
+            if (EGifPutExtensionBlock(GifFile, 255, buf) == GIF_ERROR) {
+                return GIF_ERROR;
+            }
+            buf = buf + 255;
+            length -= 255;
+        }
+        /* Output any partial block and the clear code. */
+        if (length > 0) {
+            if (EGifPutExtensionBlock(GifFile, length, buf) == GIF_ERROR) {
+                return GIF_ERROR;
+            }
+        }
+	if (EGifPutExtensionTrailer(GifFile) == GIF_ERROR) {
+	    return GIF_ERROR;
+        }
+    }
+    return GIF_OK;
+}
+
+/******************************************************************************
+ Begin an extension block (see GIF manual).  More
+ extensions can be dumped using EGifPutExtensionBlock until
+ EGifPutExtensionTrailer is invoked.
+******************************************************************************/
+int
+EGifPutExtensionLeader(GifFileType *GifFile, const int ExtCode)
+{
+    GifByteType Buf[3];
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    if (!IS_WRITEABLE(Private)) {
+        /* This file was NOT open for writing: */
+        GifFile->Error = E_GIF_ERR_NOT_WRITEABLE;
+        return GIF_ERROR;
+    }
+
+    Buf[0] = EXTENSION_INTRODUCER;
+    Buf[1] = ExtCode;
+    InternalWrite(GifFile, Buf, 2);
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ Put extension block data (see GIF manual) into a GIF file.
+******************************************************************************/
+int
+EGifPutExtensionBlock(GifFileType *GifFile, 
+		     const int ExtLen,
+		     const void *Extension)
+{
+    GifByteType Buf;
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    if (!IS_WRITEABLE(Private)) {
+        /* This file was NOT open for writing: */
+        GifFile->Error = E_GIF_ERR_NOT_WRITEABLE;
+        return GIF_ERROR;
+    }
+
+    Buf = ExtLen;
+    InternalWrite(GifFile, &Buf, 1);
+    InternalWrite(GifFile, Extension, ExtLen);
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ Put a terminating block (see GIF manual) into a GIF file.
+******************************************************************************/
+int
+EGifPutExtensionTrailer(GifFileType *GifFile) {
+
+    GifByteType Buf;
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    if (!IS_WRITEABLE(Private)) {
+        /* This file was NOT open for writing: */
+        GifFile->Error = E_GIF_ERR_NOT_WRITEABLE;
+        return GIF_ERROR;
+    }
+
+    /* Write the block terminator */
+    Buf = 0;
+    InternalWrite(GifFile, &Buf, 1);
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ Put an extension block (see GIF manual) into a GIF file.
+ Warning: This function is only useful for Extension blocks that have at
+ most one subblock.  Extensions with more than one subblock need to use the
+ EGifPutExtension{Leader,Block,Trailer} functions instead.
+******************************************************************************/
+int
+EGifPutExtension(GifFileType *GifFile,
+                 const int ExtCode,
+                 const int ExtLen,
+                 const void *Extension) {
+
+    GifByteType Buf[3];
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    if (!IS_WRITEABLE(Private)) {
+        /* This file was NOT open for writing: */
+        GifFile->Error = E_GIF_ERR_NOT_WRITEABLE;
+        return GIF_ERROR;
+    }
+
+    if (ExtCode == 0)
+        InternalWrite(GifFile, (GifByteType *)&ExtLen, 1);
+    else {
+        Buf[0] = EXTENSION_INTRODUCER;
+        Buf[1] = ExtCode;   /* Extension Label */
+        Buf[2] = ExtLen;    /* Extension length */
+        InternalWrite(GifFile, Buf, 3);
+    }
+    InternalWrite(GifFile, Extension, ExtLen);
+    Buf[0] = 0;
+    InternalWrite(GifFile, Buf, 1);
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ Render a Graphics Control Block as raw extension data
+******************************************************************************/
+
+size_t EGifGCBToExtension(const GraphicsControlBlock *GCB,
+		       GifByteType *GifExtension)
+{
+    GifExtension[0] = 0;
+    GifExtension[0] |= (GCB->TransparentColor == NO_TRANSPARENT_COLOR) ? 0x00 : 0x01;
+    GifExtension[0] |= GCB->UserInputFlag ? 0x02 : 0x00;
+    GifExtension[0] |= ((GCB->DisposalMode & 0x07) << 2);
+    GifExtension[1] = LOBYTE(GCB->DelayTime);
+    GifExtension[2] = HIBYTE(GCB->DelayTime);
+    GifExtension[3] = (char)GCB->TransparentColor;
+    return 4;
+}
+
+/******************************************************************************
+ Replace the Graphics Control Block for a saved image, if it exists.
+******************************************************************************/
+
+int EGifGCBToSavedExtension(const GraphicsControlBlock *GCB, 
+			    GifFileType *GifFile, int ImageIndex)
+{
+    int i;
+    size_t Len;
+    GifByteType buf[sizeof(GraphicsControlBlock)]; /* a bit dodgy... */
+
+    if (ImageIndex < 0 || ImageIndex > GifFile->ImageCount - 1)
+	return GIF_ERROR;
+
+    for (i = 0; i < GifFile->SavedImages[ImageIndex].ExtensionBlockCount; i++) {
+	ExtensionBlock *ep = &GifFile->SavedImages[ImageIndex].ExtensionBlocks[i];
+	if (ep->Function == GRAPHICS_EXT_FUNC_CODE) {
+	    EGifGCBToExtension(GCB, ep->Bytes);
+	    return GIF_OK;
+	}
+    }
+
+    Len = EGifGCBToExtension(GCB, (GifByteType *)buf);
+    if (GifAddExtensionBlock(&GifFile->SavedImages[ImageIndex].ExtensionBlockCount,
+			     &GifFile->SavedImages[ImageIndex].ExtensionBlocks,
+			     GRAPHICS_EXT_FUNC_CODE,
+			     Len,
+			     (unsigned char *)buf) == GIF_ERROR)
+	return (GIF_ERROR);
+
+    return (GIF_OK);
+}
+
+/******************************************************************************
+ Put the image code in compressed form. This routine can be called if the
+ information needed to be piped out as is. Obviously this is much faster
+ than decoding and encoding again. This routine should be followed by calls
+ to EGifPutCodeNext, until NULL block is given.
+ The block should NOT be freed by the user (not dynamically allocated).
+******************************************************************************/
+int
+EGifPutCode(GifFileType *GifFile, int CodeSize, const GifByteType *CodeBlock)
+{
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    if (!IS_WRITEABLE(Private)) {
+        /* This file was NOT open for writing: */
+        GifFile->Error = E_GIF_ERR_NOT_WRITEABLE;
+        return GIF_ERROR;
+    }
+
+    /* No need to dump code size as Compression set up does any for us: */
+    /* 
+     * Buf = CodeSize;
+     * if (InternalWrite(GifFile, &Buf, 1) != 1) {
+     *      GifFile->Error = E_GIF_ERR_WRITE_FAILED;
+     *      return GIF_ERROR;
+     * }
+     */
+
+    return EGifPutCodeNext(GifFile, CodeBlock);
+}
+
+/******************************************************************************
+ Continue to put the image code in compressed form. This routine should be
+ called with blocks of code as read via DGifGetCode/DGifGetCodeNext. If
+ given buffer pointer is NULL, empty block is written to mark end of code.
+******************************************************************************/
+int
+EGifPutCodeNext(GifFileType *GifFile, const GifByteType *CodeBlock)
+{
+    GifByteType Buf;
+    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
+
+    if (CodeBlock != NULL) {
+        if (InternalWrite(GifFile, CodeBlock, CodeBlock[0] + 1)
+               != (unsigned)(CodeBlock[0] + 1)) {
+            GifFile->Error = E_GIF_ERR_WRITE_FAILED;
+            return GIF_ERROR;
+        }
+    } else {
+        Buf = 0;
+        if (InternalWrite(GifFile, &Buf, 1) != 1) {
+            GifFile->Error = E_GIF_ERR_WRITE_FAILED;
+            return GIF_ERROR;
+        }
+        Private->PixelCount = 0;    /* And local info. indicate image read. */
+    }
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ This routine should be called last, to close the GIF file.
+******************************************************************************/
+int
+EGifCloseFile(GifFileType *GifFile, int *ErrorCode)
+{
+    GifByteType Buf;
+    GifFilePrivateType *Private;
+    FILE *File;
+
+    if (GifFile == NULL)
+        return GIF_ERROR;
+
+    Private = (GifFilePrivateType *) GifFile->Private;
+    if (Private == NULL)
+	return GIF_ERROR;
+    if (!IS_WRITEABLE(Private)) {
+        /* This file was NOT open for writing: */
+	if (ErrorCode != NULL)
+	    *ErrorCode = E_GIF_ERR_NOT_WRITEABLE;
+	free(GifFile);
+        return GIF_ERROR;
+    }
+
+    File = Private->File;
+
+    Buf = TERMINATOR_INTRODUCER;
+    InternalWrite(GifFile, &Buf, 1);
+
+    if (GifFile->Image.ColorMap) {
+        GifFreeMapObject(GifFile->Image.ColorMap);
+        GifFile->Image.ColorMap = NULL;
+    }
+    if (GifFile->SColorMap) {
+        GifFreeMapObject(GifFile->SColorMap);
+        GifFile->SColorMap = NULL;
+    }
+    if (Private) {
+        if (Private->HashTable) {
+            free((char *) Private->HashTable);
+        }
+	free((char *) Private);
+    }
+
+    if (File && fclose(File) != 0) {
+	if (ErrorCode != NULL)
+	    *ErrorCode = E_GIF_ERR_CLOSE_FAILED;
+	free(GifFile);
+        return GIF_ERROR;
+    }
+
+    free(GifFile);
+    if (ErrorCode != NULL)
+	*ErrorCode = E_GIF_SUCCEEDED;
+    return GIF_OK;
+}
+
+/******************************************************************************
+ Put 2 bytes (a word) into the given file in little-endian order:
+******************************************************************************/
+static int
+EGifPutWord(int Word, GifFileType *GifFile)
+{
+    unsigned char c[2];
+
+    c[0] = LOBYTE(Word);
+    c[1] = HIBYTE(Word);
+    if (InternalWrite(GifFile, c, 2) == 2)
+        return GIF_OK;
+    else
+        return GIF_ERROR;
+}
+
+/******************************************************************************
+ Setup the LZ compression for this image:
+******************************************************************************/
+static int
+EGifSetupCompress(GifFileType *GifFile)
+{
+    int BitsPerPixel;
+    GifByteType Buf;
+    GifFilePrivateType *Private = (GifFilePrivateType *) GifFile->Private;
+
+    /* Test and see what color map to use, and from it # bits per pixel: */
+    if (GifFile->Image.ColorMap)
+        BitsPerPixel = GifFile->Image.ColorMap->BitsPerPixel;
+    else if (GifFile->SColorMap)
+        BitsPerPixel = GifFile->SColorMap->BitsPerPixel;
+    else {
+        GifFile->Error = E_GIF_ERR_NO_COLOR_MAP;
+        return GIF_ERROR;
+    }
+
+    Buf = BitsPerPixel = (BitsPerPixel < 2 ? 2 : BitsPerPixel);
+    InternalWrite(GifFile, &Buf, 1);    /* Write the Code size to file. */
+
+    Private->Buf[0] = 0;    /* Nothing was output yet. */
+    Private->BitsPerPixel = BitsPerPixel;
+    Private->ClearCode = (1 << BitsPerPixel);
+    Private->EOFCode = Private->ClearCode + 1;
+    Private->RunningCode = Private->EOFCode + 1;
+    Private->RunningBits = BitsPerPixel + 1;    /* Number of bits per code. */
+    Private->MaxCode1 = 1 << Private->RunningBits;    /* Max. code + 1. */
+    Private->CrntCode = FIRST_CODE;    /* Signal that this is first one! */
+    Private->CrntShiftState = 0;    /* No information in CrntShiftDWord. */
+    Private->CrntShiftDWord = 0;
+
+   /* Clear hash table and send Clear to make sure the decoder do the same. */
+    _ClearHashTable(Private->HashTable);
+
+    if (EGifCompressOutput(GifFile, Private->ClearCode) == GIF_ERROR) {
+        GifFile->Error = E_GIF_ERR_DISK_IS_FULL;
+        return GIF_ERROR;
+    }
+    return GIF_OK;
+}
+
+/******************************************************************************
+ The LZ compression routine:
+ This version compresses the given buffer Line of length LineLen.
+ This routine can be called a few times (one per scan line, for example), in
+ order to complete the whole image.
+******************************************************************************/
+static int
+EGifCompressLine(GifFileType *GifFile,
+                 GifPixelType *Line,
+                 const int LineLen)
+{
+    int i = 0, CrntCode, NewCode;
+    unsigned long NewKey;
+    GifPixelType Pixel;
+    GifHashTableType *HashTable;
+    GifFilePrivateType *Private = (GifFilePrivateType *) GifFile->Private;
+
+    HashTable = Private->HashTable;
+
+    if (Private->CrntCode == FIRST_CODE)    /* Its first time! */
+        CrntCode = Line[i++];
+    else
+        CrntCode = Private->CrntCode;    /* Get last code in compression. */
+
+    while (i < LineLen) {   /* Decode LineLen items. */
+        Pixel = Line[i++];  /* Get next pixel from stream. */
+        /* Form a new unique key to search hash table for the code combines 
+         * CrntCode as Prefix string with Pixel as postfix char.
+         */
+        NewKey = (((uint32_t) CrntCode) << 8) + Pixel;
+        if ((NewCode = _ExistsHashTable(HashTable, NewKey)) >= 0) {
+            /* This Key is already there, or the string is old one, so
+             * simple take new code as our CrntCode:
+             */
+            CrntCode = NewCode;
+        } else {
+            /* Put it in hash table, output the prefix code, and make our
+             * CrntCode equal to Pixel.
+             */
+            if (EGifCompressOutput(GifFile, CrntCode) == GIF_ERROR) {
+                GifFile->Error = E_GIF_ERR_DISK_IS_FULL;
+                return GIF_ERROR;
+            }
+            CrntCode = Pixel;
+
+            /* If however the HashTable if full, we send a clear first and
+             * Clear the hash table.
+             */
+            if (Private->RunningCode >= LZ_MAX_CODE) {
+                /* Time to do some clearance: */
+                if (EGifCompressOutput(GifFile, Private->ClearCode)
+                        == GIF_ERROR) {
+                    GifFile->Error = E_GIF_ERR_DISK_IS_FULL;
+                    return GIF_ERROR;
+                }
+                Private->RunningCode = Private->EOFCode + 1;
+                Private->RunningBits = Private->BitsPerPixel + 1;
+                Private->MaxCode1 = 1 << Private->RunningBits;
+                _ClearHashTable(HashTable);
+            } else {
+                /* Put this unique key with its relative Code in hash table: */
+                _InsertHashTable(HashTable, NewKey, Private->RunningCode++);
+            }
+        }
+
+    }
+
+    /* Preserve the current state of the compression algorithm: */
+    Private->CrntCode = CrntCode;
+
+    if (Private->PixelCount == 0) {
+        /* We are done - output last Code and flush output buffers: */
+        if (EGifCompressOutput(GifFile, CrntCode) == GIF_ERROR) {
+            GifFile->Error = E_GIF_ERR_DISK_IS_FULL;
+            return GIF_ERROR;
+        }
+        if (EGifCompressOutput(GifFile, Private->EOFCode) == GIF_ERROR) {
+            GifFile->Error = E_GIF_ERR_DISK_IS_FULL;
+            return GIF_ERROR;
+        }
+        if (EGifCompressOutput(GifFile, FLUSH_OUTPUT) == GIF_ERROR) {
+            GifFile->Error = E_GIF_ERR_DISK_IS_FULL;
+            return GIF_ERROR;
+        }
+    }
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ The LZ compression output routine:
+ This routine is responsible for the compression of the bit stream into
+ 8 bits (bytes) packets.
+ Returns GIF_OK if written successfully.
+******************************************************************************/
+static int
+EGifCompressOutput(GifFileType *GifFile,
+                   const int Code)
+{
+    GifFilePrivateType *Private = (GifFilePrivateType *) GifFile->Private;
+    int retval = GIF_OK;
+
+    if (Code == FLUSH_OUTPUT) {
+        while (Private->CrntShiftState > 0) {
+            /* Get Rid of what is left in DWord, and flush it. */
+            if (EGifBufferedOutput(GifFile, Private->Buf,
+                                 Private->CrntShiftDWord & 0xff) == GIF_ERROR)
+                retval = GIF_ERROR;
+            Private->CrntShiftDWord >>= 8;
+            Private->CrntShiftState -= 8;
+        }
+        Private->CrntShiftState = 0;    /* For next time. */
+        if (EGifBufferedOutput(GifFile, Private->Buf,
+                               FLUSH_OUTPUT) == GIF_ERROR)
+            retval = GIF_ERROR;
+    } else {
+        Private->CrntShiftDWord |= ((long)Code) << Private->CrntShiftState;
+        Private->CrntShiftState += Private->RunningBits;
+        while (Private->CrntShiftState >= 8) {
+            /* Dump out full bytes: */
+            if (EGifBufferedOutput(GifFile, Private->Buf,
+                                 Private->CrntShiftDWord & 0xff) == GIF_ERROR)
+                retval = GIF_ERROR;
+            Private->CrntShiftDWord >>= 8;
+            Private->CrntShiftState -= 8;
+        }
+    }
+
+    /* If code cannt fit into RunningBits bits, must raise its size. Note */
+    /* however that codes above 4095 are used for special signaling.      */
+    if (Private->RunningCode >= Private->MaxCode1 && Code <= 4095) {
+       Private->MaxCode1 = 1 << ++Private->RunningBits;
+    }
+
+    return retval;
+}
+
+/******************************************************************************
+ This routines buffers the given characters until 255 characters are ready
+ to be output. If Code is equal to -1 the buffer is flushed (EOF).
+ The buffer is Dumped with first byte as its size, as GIF format requires.
+ Returns GIF_OK if written successfully.
+******************************************************************************/
+static int
+EGifBufferedOutput(GifFileType *GifFile,
+                   GifByteType *Buf,
+                   int c)
+{
+    if (c == FLUSH_OUTPUT) {
+        /* Flush everything out. */
+        if (Buf[0] != 0
+            && InternalWrite(GifFile, Buf, Buf[0] + 1) != (unsigned)(Buf[0] + 1)) {
+            GifFile->Error = E_GIF_ERR_WRITE_FAILED;
+            return GIF_ERROR;
+        }
+        /* Mark end of compressed data, by an empty block (see GIF doc): */
+        Buf[0] = 0;
+        if (InternalWrite(GifFile, Buf, 1) != 1) {
+            GifFile->Error = E_GIF_ERR_WRITE_FAILED;
+            return GIF_ERROR;
+        }
+    } else {
+        if (Buf[0] == 255) {
+            /* Dump out this buffer - it is full: */
+            if (InternalWrite(GifFile, Buf, Buf[0] + 1) != (unsigned)(Buf[0] + 1)) {
+                GifFile->Error = E_GIF_ERR_WRITE_FAILED;
+                return GIF_ERROR;
+            }
+            Buf[0] = 0;
+        }
+        Buf[++Buf[0]] = c;
+    }
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ This routine writes to disk an in-core representation of a GIF previously
+ created by DGifSlurp().
+******************************************************************************/
+
+static int
+EGifWriteExtensions(GifFileType *GifFileOut, 
+			       ExtensionBlock *ExtensionBlocks, 
+			       int ExtensionBlockCount) 
+{
+    if (ExtensionBlocks) {
+        ExtensionBlock *ep;
+	int j;
+
+	for (j = 0; j < ExtensionBlockCount; j++) {
+	    ep = &ExtensionBlocks[j];
+	    if (ep->Function != CONTINUE_EXT_FUNC_CODE)
+		if (EGifPutExtensionLeader(GifFileOut, ep->Function) == GIF_ERROR)
+		    return (GIF_ERROR);
+	    if (EGifPutExtensionBlock(GifFileOut, ep->ByteCount, ep->Bytes) == GIF_ERROR)
+		return (GIF_ERROR);
+	    if (j == ExtensionBlockCount - 1 || (ep+1)->Function != CONTINUE_EXT_FUNC_CODE)
+		if (EGifPutExtensionTrailer(GifFileOut) == GIF_ERROR)
+		    return (GIF_ERROR);
+	}
+    }
+
+    return (GIF_OK);
+}
+
+int
+EGifSpew(GifFileType *GifFileOut) 
+{
+    int i, j; 
+
+    if (EGifPutScreenDesc(GifFileOut,
+                          GifFileOut->SWidth,
+                          GifFileOut->SHeight,
+                          GifFileOut->SColorResolution,
+                          GifFileOut->SBackGroundColor,
+                          GifFileOut->SColorMap) == GIF_ERROR) {
+        return (GIF_ERROR);
+    }
+
+    for (i = 0; i < GifFileOut->ImageCount; i++) {
+        SavedImage *sp = &GifFileOut->SavedImages[i];
+        int SavedHeight = sp->ImageDesc.Height;
+        int SavedWidth = sp->ImageDesc.Width;
+
+        /* this allows us to delete images by nuking their rasters */
+        if (sp->RasterBits == NULL)
+            continue;
+
+	if (EGifWriteExtensions(GifFileOut, 
+				sp->ExtensionBlocks,
+				sp->ExtensionBlockCount) == GIF_ERROR)
+	    return (GIF_ERROR);
+
+        if (EGifPutImageDesc(GifFileOut,
+                             sp->ImageDesc.Left,
+                             sp->ImageDesc.Top,
+                             SavedWidth,
+                             SavedHeight,
+                             sp->ImageDesc.Interlace,
+                             sp->ImageDesc.ColorMap) == GIF_ERROR)
+            return (GIF_ERROR);
+
+	if (sp->ImageDesc.Interlace) {
+	     /* 
+	      * The way an interlaced image should be written - 
+	      * offsets and jumps...
+	      */
+	    int InterlacedOffset[] = { 0, 4, 2, 1 };
+	    int InterlacedJumps[] = { 8, 8, 4, 2 };
+	    int k;
+	    /* Need to perform 4 passes on the images: */
+	    for (k = 0; k < 4; k++)
+		for (j = InterlacedOffset[k]; 
+		     j < SavedHeight;
+		     j += InterlacedJumps[k]) {
+		    if (EGifPutLine(GifFileOut, 
+				    sp->RasterBits + j * SavedWidth, 
+				    SavedWidth)	== GIF_ERROR)
+			return (GIF_ERROR);
+		}
+	} else {
+	    for (j = 0; j < SavedHeight; j++) {
+		if (EGifPutLine(GifFileOut,
+				sp->RasterBits + j * SavedWidth,
+				SavedWidth) == GIF_ERROR)
+		    return (GIF_ERROR);
+	    }
+	}
+    }
+
+    if (EGifWriteExtensions(GifFileOut,
+			    GifFileOut->ExtensionBlocks,
+			    GifFileOut->ExtensionBlockCount) == GIF_ERROR)
+	return (GIF_ERROR);
+
+    if (EGifCloseFile(GifFileOut, NULL) == GIF_ERROR)
+        return (GIF_ERROR);
+
+    return (GIF_OK);
+}
+
+/* end */
diff --git a/Src/external_dependencies/giflib/gif_err.c b/Src/external_dependencies/giflib/gif_err.c
new file mode 100644
index 00000000..3ec2a56f
--- /dev/null
+++ b/Src/external_dependencies/giflib/gif_err.c
@@ -0,0 +1,97 @@
+/*****************************************************************************
+
+gif_err.c - handle error reporting for the GIF library.
+
+****************************************************************************/
+
+#include <stdio.h>
+
+#include "gif_lib.h"
+#include "gif_lib_private.h"
+
+/*****************************************************************************
+ Return a string description of  the last GIF error
+*****************************************************************************/
+const char *
+GifErrorString(int ErrorCode)
+{
+    const char *Err;
+
+    switch (ErrorCode) {
+      case E_GIF_ERR_OPEN_FAILED:
+        Err = "Failed to open given file";
+        break;
+      case E_GIF_ERR_WRITE_FAILED:
+        Err = "Failed to write to given file";
+        break;
+      case E_GIF_ERR_HAS_SCRN_DSCR:
+        Err = "Screen descriptor has already been set";
+        break;
+      case E_GIF_ERR_HAS_IMAG_DSCR:
+        Err = "Image descriptor is still active";
+        break;
+      case E_GIF_ERR_NO_COLOR_MAP:
+        Err = "Neither global nor local color map";
+        break;
+      case E_GIF_ERR_DATA_TOO_BIG:
+        Err = "Number of pixels bigger than width * height";
+        break;
+      case E_GIF_ERR_NOT_ENOUGH_MEM:
+        Err = "Failed to allocate required memory";
+        break;
+      case E_GIF_ERR_DISK_IS_FULL:
+        Err = "Write failed (disk full?)";
+        break;
+      case E_GIF_ERR_CLOSE_FAILED:
+        Err = "Failed to close given file";
+        break;
+      case E_GIF_ERR_NOT_WRITEABLE:
+        Err = "Given file was not opened for write";
+        break;
+      case D_GIF_ERR_OPEN_FAILED:
+        Err = "Failed to open given file";
+        break;
+      case D_GIF_ERR_READ_FAILED:
+        Err = "Failed to read from given file";
+        break;
+      case D_GIF_ERR_NOT_GIF_FILE:
+        Err = "Data is not in GIF format";
+        break;
+      case D_GIF_ERR_NO_SCRN_DSCR:
+        Err = "No screen descriptor detected";
+        break;
+      case D_GIF_ERR_NO_IMAG_DSCR:
+        Err = "No Image Descriptor detected";
+        break;
+      case D_GIF_ERR_NO_COLOR_MAP:
+        Err = "Neither global nor local color map";
+        break;
+      case D_GIF_ERR_WRONG_RECORD:
+        Err = "Wrong record type detected";
+        break;
+      case D_GIF_ERR_DATA_TOO_BIG:
+        Err = "Number of pixels bigger than width * height";
+        break;
+      case D_GIF_ERR_NOT_ENOUGH_MEM:
+        Err = "Failed to allocate required memory";
+        break;
+      case D_GIF_ERR_CLOSE_FAILED:
+        Err = "Failed to close given file";
+        break;
+      case D_GIF_ERR_NOT_READABLE:
+        Err = "Given file was not opened for read";
+        break;
+      case D_GIF_ERR_IMAGE_DEFECT:
+        Err = "Image is defective, decoding aborted";
+        break;
+      case D_GIF_ERR_EOF_TOO_SOON:
+        Err = "Image EOF detected before image complete";
+        break;
+      default:
+        Err = NULL;
+        break;
+    }
+    return Err;
+}
+
+/* end */
diff --git a/Src/external_dependencies/giflib/gif_font.c b/Src/external_dependencies/giflib/gif_font.c
new file mode 100644
index 00000000..8a02b2d8
--- /dev/null
+++ b/Src/external_dependencies/giflib/gif_font.c
@@ -0,0 +1,259 @@
+/*****************************************************************************
+ 
+gif_font.c - utility font handling and simple drawing for the GIF library
+ 
+****************************************************************************/
+
+#include <string.h>
+#include <stdlib.h>
+
+#include "gif_lib.h"
+
+/*****************************************************************************
+ Ascii 8 by 8 regular font - only first 128 characters are supported.
+*****************************************************************************/
+
+/*
+ * Each array entry holds the bits for 8 horizontal scan lines, topmost
+ * first.  The most significant bit of each constant is the leftmost bit of
+ * the scan line.
+ */
+/*@+charint@*/
+const unsigned char GifAsciiTable8x8[][GIF_FONT_WIDTH] = {
+    {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},    /* Ascii 0 */
+    {0x3c, 0x42, 0xa5, 0x81, 0xbd, 0x42, 0x3c, 0x00},    /* Ascii 1 */
+    {0x3c, 0x7e, 0xdb, 0xff, 0xc3, 0x7e, 0x3c, 0x00},    /* Ascii 2 */
+    {0x00, 0xee, 0xfe, 0xfe, 0x7c, 0x38, 0x10, 0x00},    /* Ascii 3 */
+    {0x10, 0x38, 0x7c, 0xfe, 0x7c, 0x38, 0x10, 0x00},    /* Ascii 4 */
+    {0x00, 0x3c, 0x18, 0xff, 0xff, 0x08, 0x18, 0x00},    /* Ascii 5 */
+    {0x10, 0x38, 0x7c, 0xfe, 0xfe, 0x10, 0x38, 0x00},    /* Ascii 6 */
+    {0x00, 0x00, 0x18, 0x3c, 0x18, 0x00, 0x00, 0x00},    /* Ascii 7 */
+    {0xff, 0xff, 0xe7, 0xc3, 0xe7, 0xff, 0xff, 0xff},    /* Ascii 8 */
+    {0x00, 0x3c, 0x42, 0x81, 0x81, 0x42, 0x3c, 0x00},    /* Ascii 9 */
+    {0xff, 0xc3, 0xbd, 0x7e, 0x7e, 0xbd, 0xc3, 0xff},    /* Ascii 10 */
+    {0x1f, 0x07, 0x0d, 0x7c, 0xc6, 0xc6, 0x7c, 0x00},    /* Ascii 11 */
+    {0x00, 0x7e, 0xc3, 0xc3, 0x7e, 0x18, 0x7e, 0x18},    /* Ascii 12 */
+    {0x04, 0x06, 0x07, 0x04, 0x04, 0xfc, 0xf8, 0x00},    /* Ascii 13 */
+    {0x0c, 0x0a, 0x0d, 0x0b, 0xf9, 0xf9, 0x1f, 0x1f},    /* Ascii 14 */
+    {0x00, 0x92, 0x7c, 0x44, 0xc6, 0x7c, 0x92, 0x00},    /* Ascii 15 */
+    {0x00, 0x00, 0x60, 0x78, 0x7e, 0x78, 0x60, 0x00},    /* Ascii 16 */
+    {0x00, 0x00, 0x06, 0x1e, 0x7e, 0x1e, 0x06, 0x00},    /* Ascii 17 */
+    {0x18, 0x7e, 0x18, 0x18, 0x18, 0x18, 0x7e, 0x18},    /* Ascii 18 */
+    {0x66, 0x66, 0x66, 0x66, 0x66, 0x00, 0x66, 0x00},    /* Ascii 19 */
+    {0xff, 0xb6, 0x76, 0x36, 0x36, 0x36, 0x36, 0x00},    /* Ascii 20 */
+    {0x7e, 0xc1, 0xdc, 0x22, 0x22, 0x1f, 0x83, 0x7e},    /* Ascii 21 */
+    {0x00, 0x00, 0x00, 0x7e, 0x7e, 0x00, 0x00, 0x00},    /* Ascii 22 */
+    {0x18, 0x7e, 0x18, 0x18, 0x7e, 0x18, 0x00, 0xff},    /* Ascii 23 */
+    {0x18, 0x7e, 0x18, 0x18, 0x18, 0x18, 0x18, 0x00},    /* Ascii 24 */
+    {0x18, 0x18, 0x18, 0x18, 0x18, 0x7e, 0x18, 0x00},    /* Ascii 25 */
+    {0x00, 0x04, 0x06, 0xff, 0x06, 0x04, 0x00, 0x00},    /* Ascii 26 */
+    {0x00, 0x20, 0x60, 0xff, 0x60, 0x20, 0x00, 0x00},    /* Ascii 27 */
+    {0x00, 0x00, 0x00, 0xc0, 0xc0, 0xc0, 0xff, 0x00},    /* Ascii 28 */
+    {0x00, 0x24, 0x66, 0xff, 0x66, 0x24, 0x00, 0x00},    /* Ascii 29 */
+    {0x00, 0x00, 0x10, 0x38, 0x7c, 0xfe, 0x00, 0x00},    /* Ascii 30 */
+    {0x00, 0x00, 0x00, 0xfe, 0x7c, 0x38, 0x10, 0x00},    /* Ascii 31 */
+    {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},    /* */
+    {0x30, 0x30, 0x30, 0x30, 0x30, 0x00, 0x30, 0x00},    /* ! */
+    {0x66, 0x66, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},    /* " */
+    {0x6c, 0x6c, 0xfe, 0x6c, 0xfe, 0x6c, 0x6c, 0x00},    /* # */
+    {0x10, 0x7c, 0xd2, 0x7c, 0x86, 0x7c, 0x10, 0x00},    /* $ */
+    {0xf0, 0x96, 0xfc, 0x18, 0x3e, 0x72, 0xde, 0x00},    /* % */
+    {0x30, 0x48, 0x30, 0x78, 0xce, 0xcc, 0x78, 0x00},    /* & */
+    {0x0c, 0x0c, 0x18, 0x00, 0x00, 0x00, 0x00, 0x00},    /* ' */
+    {0x10, 0x60, 0xc0, 0xc0, 0xc0, 0x60, 0x10, 0x00},    /* ( */
+    {0x10, 0x0c, 0x06, 0x06, 0x06, 0x0c, 0x10, 0x00},    /* ) */
+    {0x00, 0x54, 0x38, 0xfe, 0x38, 0x54, 0x00, 0x00},    /* * */
+    {0x00, 0x18, 0x18, 0x7e, 0x18, 0x18, 0x00, 0x00},    /* + */
+    {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x18, 0x70},    /* , */
+    {0x00, 0x00, 0x00, 0x7e, 0x00, 0x00, 0x00, 0x00},    /* - */
+    {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x18, 0x00},    /* . */
+    {0x02, 0x06, 0x0c, 0x18, 0x30, 0x60, 0xc0, 0x00},    /* / */
+    {0x7c, 0xc6, 0xc6, 0xc6, 0xc6, 0xc6, 0x7c, 0x00},    /* 0 */
+    {0x18, 0x38, 0x78, 0x18, 0x18, 0x18, 0x3c, 0x00},    /* 1 */
+    {0x7c, 0xc6, 0x06, 0x0c, 0x30, 0x60, 0xfe, 0x00},    /* 2 */
+    {0x7c, 0xc6, 0x06, 0x3c, 0x06, 0xc6, 0x7c, 0x00},    /* 3 */
+    {0x0e, 0x1e, 0x36, 0x66, 0xfe, 0x06, 0x06, 0x00},    /* 4 */
+    {0xfe, 0xc0, 0xc0, 0xfc, 0x06, 0x06, 0xfc, 0x00},    /* 5 */
+    {0x7c, 0xc6, 0xc0, 0xfc, 0xc6, 0xc6, 0x7c, 0x00},    /* 6 */
+    {0xfe, 0x06, 0x0c, 0x18, 0x30, 0x60, 0x60, 0x00},    /* 7 */
+    {0x7c, 0xc6, 0xc6, 0x7c, 0xc6, 0xc6, 0x7c, 0x00},    /* 8 */
+    {0x7c, 0xc6, 0xc6, 0x7e, 0x06, 0xc6, 0x7c, 0x00},    /* 9 */
+    {0x00, 0x30, 0x00, 0x00, 0x00, 0x30, 0x00, 0x00},    /* : */
+    {0x00, 0x30, 0x00, 0x00, 0x00, 0x30, 0x20, 0x00},    /* }, */
+    {0x00, 0x1c, 0x30, 0x60, 0x30, 0x1c, 0x00, 0x00},    /* < */
+    {0x00, 0x00, 0x7e, 0x00, 0x7e, 0x00, 0x00, 0x00},    /* = */
+    {0x00, 0x70, 0x18, 0x0c, 0x18, 0x70, 0x00, 0x00},    /* > */
+    {0x7c, 0xc6, 0x0c, 0x18, 0x30, 0x00, 0x30, 0x00},    /* ? */
+    {0x7c, 0x82, 0x9a, 0xaa, 0xaa, 0x9e, 0x7c, 0x00},    /* @ */
+    {0x38, 0x6c, 0xc6, 0xc6, 0xfe, 0xc6, 0xc6, 0x00},    /* A */
+    {0xfc, 0xc6, 0xc6, 0xfc, 0xc6, 0xc6, 0xfc, 0x00},    /* B */
+    {0x7c, 0xc6, 0xc6, 0xc0, 0xc0, 0xc6, 0x7c, 0x00},    /* C */
+    {0xf8, 0xcc, 0xc6, 0xc6, 0xc6, 0xcc, 0xf8, 0x00},    /* D */
+    {0xfe, 0xc0, 0xc0, 0xfc, 0xc0, 0xc0, 0xfe, 0x00},    /* E */
+    {0xfe, 0xc0, 0xc0, 0xfc, 0xc0, 0xc0, 0xc0, 0x00},    /* F */
+    {0x7c, 0xc6, 0xc0, 0xce, 0xc6, 0xc6, 0x7e, 0x00},    /* G */
+    {0xc6, 0xc6, 0xc6, 0xfe, 0xc6, 0xc6, 0xc6, 0x00},    /* H */
+    {0x78, 0x30, 0x30, 0x30, 0x30, 0x30, 0x78, 0x00},    /* I */
+    {0x1e, 0x06, 0x06, 0x06, 0xc6, 0xc6, 0x7c, 0x00},    /* J */
+    {0xc6, 0xcc, 0xd8, 0xf0, 0xd8, 0xcc, 0xc6, 0x00},    /* K */
+    {0xc0, 0xc0, 0xc0, 0xc0, 0xc0, 0xc0, 0xfe, 0x00},    /* L */
+    {0xc6, 0xee, 0xfe, 0xd6, 0xc6, 0xc6, 0xc6, 0x00},    /* M */
+    {0xc6, 0xe6, 0xf6, 0xde, 0xce, 0xc6, 0xc6, 0x00},    /* N */
+    {0x7c, 0xc6, 0xc6, 0xc6, 0xc6, 0xc6, 0x7c, 0x00},    /* O */
+    {0xfc, 0xc6, 0xc6, 0xfc, 0xc0, 0xc0, 0xc0, 0x00},    /* P */
+    {0x7c, 0xc6, 0xc6, 0xc6, 0xc6, 0xc6, 0x7c, 0x06},    /* Q */
+    {0xfc, 0xc6, 0xc6, 0xfc, 0xc6, 0xc6, 0xc6, 0x00},    /* R */
+    {0x78, 0xcc, 0x60, 0x30, 0x18, 0xcc, 0x78, 0x00},    /* S */
+    {0xfc, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x00},    /* T */
+    {0xc6, 0xc6, 0xc6, 0xc6, 0xc6, 0xc6, 0x7c, 0x00},    /* U */
+    {0xc6, 0xc6, 0xc6, 0xc6, 0xc6, 0x6c, 0x38, 0x00},    /* V */
+    {0xc6, 0xc6, 0xc6, 0xd6, 0xfe, 0xee, 0xc6, 0x00},    /* W */
+    {0xc6, 0xc6, 0x6c, 0x38, 0x6c, 0xc6, 0xc6, 0x00},    /* X */
+    {0xc3, 0xc3, 0x66, 0x3c, 0x18, 0x18, 0x18, 0x00},    /* Y */
+    {0xfe, 0x0c, 0x18, 0x30, 0x60, 0xc0, 0xfe, 0x00},    /* Z */
+    {0x3c, 0x30, 0x30, 0x30, 0x30, 0x30, 0x3c, 0x00},    /* [ */
+    {0xc0, 0x60, 0x30, 0x18, 0x0c, 0x06, 0x03, 0x00},    /* \ */
+    {0x3c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x3c, 0x00},    /* ] */
+    {0x00, 0x38, 0x6c, 0xc6, 0x00, 0x00, 0x00, 0x00},    /* ^ */
+    {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff},    /* _ */
+    {0x30, 0x30, 0x18, 0x00, 0x00, 0x00, 0x00, 0x00},    /* ` */
+    {0x00, 0x00, 0x7c, 0x06, 0x7e, 0xc6, 0x7e, 0x00},    /* a */
+    {0xc0, 0xc0, 0xfc, 0xc6, 0xc6, 0xe6, 0xdc, 0x00},    /* b */
+    {0x00, 0x00, 0x7c, 0xc6, 0xc0, 0xc0, 0x7e, 0x00},    /* c */
+    {0x06, 0x06, 0x7e, 0xc6, 0xc6, 0xce, 0x76, 0x00},    /* d */
+    {0x00, 0x00, 0x7c, 0xc6, 0xfe, 0xc0, 0x7e, 0x00},    /* e */
+    {0x1e, 0x30, 0x7c, 0x30, 0x30, 0x30, 0x30, 0x00},    /* f */
+    {0x00, 0x00, 0x7e, 0xc6, 0xce, 0x76, 0x06, 0x7c},    /* g */
+    {0xc0, 0xc0, 0xfc, 0xc6, 0xc6, 0xc6, 0xc6, 0x00},    /* */
+    {0x18, 0x00, 0x38, 0x18, 0x18, 0x18, 0x3c, 0x00},    /* i */
+    {0x18, 0x00, 0x38, 0x18, 0x18, 0x18, 0x18, 0xf0},    /* j */
+    {0xc0, 0xc0, 0xcc, 0xd8, 0xf0, 0xd8, 0xcc, 0x00},    /* k */
+    {0x38, 0x18, 0x18, 0x18, 0x18, 0x18, 0x3c, 0x00},    /* l */
+    {0x00, 0x00, 0xcc, 0xfe, 0xd6, 0xc6, 0xc6, 0x00},    /* m */
+    {0x00, 0x00, 0xfc, 0xc6, 0xc6, 0xc6, 0xc6, 0x00},    /* n */
+    {0x00, 0x00, 0x7c, 0xc6, 0xc6, 0xc6, 0x7c, 0x00},    /* o */
+    {0x00, 0x00, 0xfc, 0xc6, 0xc6, 0xe6, 0xdc, 0xc0},    /* p */
+    {0x00, 0x00, 0x7e, 0xc6, 0xc6, 0xce, 0x76, 0x06},    /* q */
+    {0x00, 0x00, 0x6e, 0x70, 0x60, 0x60, 0x60, 0x00},    /* r */
+    {0x00, 0x00, 0x7c, 0xc0, 0x7c, 0x06, 0xfc, 0x00},    /* s */
+    {0x30, 0x30, 0x7c, 0x30, 0x30, 0x30, 0x1c, 0x00},    /* t */
+    {0x00, 0x00, 0xc6, 0xc6, 0xc6, 0xc6, 0x7e, 0x00},    /* u */
+    {0x00, 0x00, 0xc6, 0xc6, 0xc6, 0x6c, 0x38, 0x00},    /* v */
+    {0x00, 0x00, 0xc6, 0xc6, 0xd6, 0xfe, 0x6c, 0x00},    /* w */
+    {0x00, 0x00, 0xc6, 0x6c, 0x38, 0x6c, 0xc6, 0x00},    /* x */
+    {0x00, 0x00, 0xc6, 0xc6, 0xce, 0x76, 0x06, 0x7c},    /* y */
+    {0x00, 0x00, 0xfc, 0x18, 0x30, 0x60, 0xfc, 0x00},    /* z */
+    {0x0e, 0x18, 0x18, 0x70, 0x18, 0x18, 0x0e, 0x00},    /* { */
+    {0x18, 0x18, 0x18, 0x00, 0x18, 0x18, 0x18, 0x00},    /* | */
+    {0xe0, 0x30, 0x30, 0x1c, 0x30, 0x30, 0xe0, 0x00},    /* } */
+    {0x00, 0x00, 0x70, 0x9a, 0x0e, 0x00, 0x00, 0x00},    /* ~ */
+    {0x00, 0x00, 0x18, 0x3c, 0x66, 0xff, 0x00, 0x00}    /* Ascii 127 */
+};
+/*@=charint@*/
+
+void
+GifDrawText8x8(SavedImage *Image, 
+	    const int x, const int y,
+	    const char *legend,
+	    const int color)
+{
+    int i, j;
+    int base;
+    const char *cp;
+
+    for (i = 0; i < GIF_FONT_HEIGHT; i++) {
+        base = Image->ImageDesc.Width * (y + i) + x;
+
+        for (cp = legend; *cp; cp++)
+            for (j = 0; j < GIF_FONT_WIDTH; j++) {
+                if (GifAsciiTable8x8[(short)(*cp)][i] & (1 << (GIF_FONT_WIDTH - j)))
+                    Image->RasterBits[base] = color;
+                base++;
+            }
+    }
+}
+
+void
+GifDrawBox(SavedImage *Image,
+	   const int x, const int y,
+	   const int w, const int d,
+	   const int color)
+{
+    int j, base = Image->ImageDesc.Width * y + x;
+
+    for (j = 0; j < w; j++)
+        Image->RasterBits[base + j] =
+            Image->RasterBits[base + (d * Image->ImageDesc.Width) + j] = color;
+
+    for (j = 0; j < d; j++)
+        Image->RasterBits[base + j * Image->ImageDesc.Width] =
+            Image->RasterBits[base + j * Image->ImageDesc.Width + w] = color;
+}
+
+void
+GifDrawRectangle(SavedImage *Image,
+              const int x, const int y,
+              const int w, const int d,
+              const int color)
+{
+    unsigned char *bp = Image->RasterBits + Image->ImageDesc.Width * y + x;
+    int i;
+
+    for (i = 0; i < d; i++)
+        memset(bp + (i * Image->ImageDesc.Width), color, (size_t)w);
+}
+
+void
+GifDrawBoxedText8x8(SavedImage *Image,
+              const int x, const int y,
+              const char *legend,
+              const int border,
+              const int bg, const int fg)
+{
+    int j = 0, LineCount = 0, TextWidth = 0;
+    const char *cp;
+    char *dup;
+
+    /* compute size of text to box */
+    for (cp = legend; *cp; cp++)
+        if (*cp == '\r') {
+            if (j > TextWidth)
+                TextWidth = j;
+            j = 0;
+            LineCount++;
+        } else if (*cp != '\t')
+            ++j;
+    LineCount++;    /* count last line */
+    if (j > TextWidth)    /* last line might be longer than any previous */
+        TextWidth = j;
+
+    /* draw the text */
+    dup = malloc(strlen(legend)+1);
+    /* FIXME: should return bad status, but that would require API change */
+    if (dup != NULL) {
+	int i = 0;
+	/* fill the box */
+	GifDrawRectangle(Image, x + 1, y + 1,
+		      border + TextWidth * GIF_FONT_WIDTH + border - 1,
+		      border + LineCount * GIF_FONT_HEIGHT + border - 1, bg);
+	(void)strcpy(dup, (char *)legend);
+	cp = strtok((char *)dup, "\r\n");
+	do {
+	    int leadspace = 0;
+
+	    if (cp[0] == '\t')
+		leadspace = (TextWidth - strlen(++cp)) / 2;
+
+	    GifDrawText8x8(Image, x + border + (leadspace * GIF_FONT_WIDTH),
+			   y + border + (GIF_FONT_HEIGHT * i++), cp, fg);
+	    cp = strtok((char *)NULL, "\r\n");
+	} while (cp);
+	(void)free((void *)dup);
+
+	/* outline the box */
+	GifDrawBox(Image, x, y, border + TextWidth * GIF_FONT_WIDTH + border,
+		   border + LineCount * GIF_FONT_HEIGHT + border, fg);
+    }
+}
+
+/* end */
diff --git a/Src/external_dependencies/giflib/gif_hash.c b/Src/external_dependencies/giflib/gif_hash.c
new file mode 100644
index 00000000..4238c9cf
--- /dev/null
+++ b/Src/external_dependencies/giflib/gif_hash.c
@@ -0,0 +1,132 @@
+/*****************************************************************************
+
+gif_hash.c -- module to support the following operations:
+
+1. InitHashTable - initialize hash table.
+2. ClearHashTable - clear the hash table to an empty state.
+2. InsertHashTable - insert one item into data structure.
+3. ExistsHashTable - test if item exists in data structure.
+
+This module is used to hash the GIF codes during encoding.
+
+*****************************************************************************/
+
+//#include <unistd.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "gif_lib.h"
+#include "gif_hash.h"
+#include "gif_lib_private.h"
+
+/* #define  DEBUG_HIT_RATE    Debug number of misses per hash Insert/Exists. */
+
+#ifdef	DEBUG_HIT_RATE
+static long NumberOfTests = 0,
+	    NumberOfMisses = 0;
+#endif	/* DEBUG_HIT_RATE */
+
+static int KeyItem(uint32_t Item);
+
+/******************************************************************************
+ Initialize HashTable - allocate the memory needed and clear it.	      *
+******************************************************************************/
+GifHashTableType *_InitHashTable(void)
+{
+    GifHashTableType *HashTable;
+
+    if ((HashTable = (GifHashTableType *) malloc(sizeof(GifHashTableType)))
+	== NULL)
+	return NULL;
+
+    _ClearHashTable(HashTable);
+
+    return HashTable;
+}
+
+/******************************************************************************
+ Routine to clear the HashTable to an empty state.			      *
+ This part is a little machine depended. Use the commented part otherwise.   *
+******************************************************************************/
+void _ClearHashTable(GifHashTableType *HashTable)
+{
+    memset(HashTable -> HTable, 0xFF, HT_SIZE * sizeof(uint32_t));
+}
+
+/******************************************************************************
+ Routine to insert a new Item into the HashTable. The data is assumed to be  *
+ new one.								      *
+******************************************************************************/
+void _InsertHashTable(GifHashTableType *HashTable, uint32_t Key, int Code)
+{
+    int HKey = KeyItem(Key);
+    uint32_t *HTable = HashTable -> HTable;
+
+#ifdef DEBUG_HIT_RATE
+	NumberOfTests++;
+	NumberOfMisses++;
+#endif /* DEBUG_HIT_RATE */
+
+    while (HT_GET_KEY(HTable[HKey]) != 0xFFFFFL) {
+#ifdef DEBUG_HIT_RATE
+	    NumberOfMisses++;
+#endif /* DEBUG_HIT_RATE */
+	HKey = (HKey + 1) & HT_KEY_MASK;
+    }
+    HTable[HKey] = HT_PUT_KEY(Key) | HT_PUT_CODE(Code);
+}
+
+/******************************************************************************
+ Routine to test if given Key exists in HashTable and if so returns its code *
+ Returns the Code if key was found, -1 if not.				      *
+******************************************************************************/
+int _ExistsHashTable(GifHashTableType *HashTable, uint32_t Key)
+{
+    int HKey = KeyItem(Key);
+    uint32_t *HTable = HashTable -> HTable, HTKey;
+
+#ifdef DEBUG_HIT_RATE
+	NumberOfTests++;
+	NumberOfMisses++;
+#endif /* DEBUG_HIT_RATE */
+
+    while ((HTKey = HT_GET_KEY(HTable[HKey])) != 0xFFFFFL) {
+#ifdef DEBUG_HIT_RATE
+	    NumberOfMisses++;
+#endif /* DEBUG_HIT_RATE */
+	if (Key == HTKey) return HT_GET_CODE(HTable[HKey]);
+	HKey = (HKey + 1) & HT_KEY_MASK;
+    }
+
+    return -1;
+}
+
+/******************************************************************************
+ Routine to generate an HKey for the hashtable out of the given unique key.  *
+ The given Key is assumed to be 20 bits as follows: lower 8 bits are the     *
+ new postfix character, while the upper 12 bits are the prefix code.	      *
+ Because the average hit ratio is only 2 (2 hash references per entry),      *
+ evaluating more complex keys (such as twin prime keys) does not worth it!   *
+******************************************************************************/
+static int KeyItem(uint32_t Item)
+{
+    return ((Item >> 12) ^ Item) & HT_KEY_MASK;
+}
+
+#ifdef	DEBUG_HIT_RATE
+/******************************************************************************
+ Debugging routine to print the hit ratio - number of times the hash table   *
+ was tested per operation. This routine was used to test the KeyItem routine *
+******************************************************************************/
+void HashTablePrintHitRatio(void)
+{
+    printf("Hash Table Hit Ratio is %ld/%ld = %ld%%.\n",
+	NumberOfMisses, NumberOfTests,
+	NumberOfMisses * 100 / NumberOfTests);
+}
+#endif	/* DEBUG_HIT_RATE */
+
+/* end */
diff --git a/Src/external_dependencies/giflib/gif_hash.h b/Src/external_dependencies/giflib/gif_hash.h
new file mode 100644
index 00000000..a236bb56
--- /dev/null
+++ b/Src/external_dependencies/giflib/gif_hash.h
@@ -0,0 +1,39 @@
+/******************************************************************************
+
+gif_hash.h - magfic constants and declarations for GIF LZW
+
+******************************************************************************/
+
+#ifndef _GIF_HASH_H_
+#define _GIF_HASH_H_
+
+//#include <unistd.h>
+#include <stdint.h>
+
+#define HT_SIZE			8192	   /* 12bits = 4096 or twice as big! */
+#define HT_KEY_MASK		0x1FFF			      /* 13bits keys */
+#define HT_KEY_NUM_BITS		13			      /* 13bits keys */
+#define HT_MAX_KEY		8191	/* 13bits - 1, maximal code possible */
+#define HT_MAX_CODE		4095	/* Biggest code possible in 12 bits. */
+
+/* The 32 bits of the long are divided into two parts for the key & code:   */
+/* 1. The code is 12 bits as our compression algorithm is limited to 12bits */
+/* 2. The key is 12 bits Prefix code + 8 bit new char or 20 bits.	    */
+/* The key is the upper 20 bits.  The code is the lower 12. */
+#define HT_GET_KEY(l)	(l >> 12)
+#define HT_GET_CODE(l)	(l & 0x0FFF)
+#define HT_PUT_KEY(l)	(l << 12)
+#define HT_PUT_CODE(l)	(l & 0x0FFF)
+
+typedef struct GifHashTableType {
+    uint32_t HTable[HT_SIZE];
+} GifHashTableType;
+
+GifHashTableType *_InitHashTable(void);
+void _ClearHashTable(GifHashTableType *HashTable);
+void _InsertHashTable(GifHashTableType *HashTable, uint32_t Key, int Code);
+int _ExistsHashTable(GifHashTableType *HashTable, uint32_t Key);
+
+#endif /* _GIF_HASH_H_ */
+
+/* end */
diff --git a/Src/external_dependencies/giflib/gif_lib.h b/Src/external_dependencies/giflib/gif_lib.h
new file mode 100644
index 00000000..7284891f
--- /dev/null
+++ b/Src/external_dependencies/giflib/gif_lib.h
@@ -0,0 +1,314 @@
+/******************************************************************************
+ 
+gif_lib.h - service library for decoding and encoding GIF images
+                                                                             
+*****************************************************************************/
+
+#ifndef _GIF_LIB_H_
+#define _GIF_LIB_H_ 1
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+#define GIFLIB_MAJOR 5
+#define GIFLIB_MINOR 1
+#define GIFLIB_RELEASE 4
+
+#define GIF_ERROR   0
+#define GIF_OK      1
+
+#include <stddef.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#define GIF_STAMP "GIFVER"          /* First chars in file - GIF stamp.  */
+#define GIF_STAMP_LEN sizeof(GIF_STAMP) - 1
+#define GIF_VERSION_POS 3           /* Version first character in stamp. */
+#define GIF87_STAMP "GIF87a"        /* First chars in file - GIF stamp.  */
+#define GIF89_STAMP "GIF89a"        /* First chars in file - GIF stamp.  */
+
+typedef unsigned char GifPixelType;
+typedef unsigned char *GifRowType;
+typedef unsigned char GifByteType;
+typedef unsigned int GifPrefixType;
+typedef int GifWord;
+
+typedef struct GifColorType {
+    GifByteType Red, Green, Blue;
+} GifColorType;
+
+typedef struct ColorMapObject {
+    int ColorCount;
+    int BitsPerPixel;
+    bool SortFlag;
+    GifColorType *Colors;    /* on malloc(3) heap */
+} ColorMapObject;
+
+typedef struct GifImageDesc {
+    GifWord Left, Top, Width, Height;   /* Current image dimensions. */
+    bool Interlace;                     /* Sequential/Interlaced lines. */
+    ColorMapObject *ColorMap;           /* The local color map */
+} GifImageDesc;
+
+typedef struct ExtensionBlock {
+    int ByteCount;
+    GifByteType *Bytes; /* on malloc(3) heap */
+    int Function;       /* The block function code */
+#define CONTINUE_EXT_FUNC_CODE    0x00    /* continuation subblock */
+#define COMMENT_EXT_FUNC_CODE     0xfe    /* comment */
+#define GRAPHICS_EXT_FUNC_CODE    0xf9    /* graphics control (GIF89) */
+#define PLAINTEXT_EXT_FUNC_CODE   0x01    /* plaintext */
+#define APPLICATION_EXT_FUNC_CODE 0xff    /* application block */
+} ExtensionBlock;
+
+typedef struct SavedImage {
+    GifImageDesc ImageDesc;
+    GifByteType *RasterBits;         /* on malloc(3) heap */
+    int ExtensionBlockCount;         /* Count of extensions before image */    
+    ExtensionBlock *ExtensionBlocks; /* Extensions before image */    
+} SavedImage;
+
+typedef struct GifFileType {
+    GifWord SWidth, SHeight;         /* Size of virtual canvas */
+    GifWord SColorResolution;        /* How many colors can we generate? */
+    GifWord SBackGroundColor;        /* Background color for virtual canvas */
+    GifByteType AspectByte;	     /* Used to compute pixel aspect ratio */
+    ColorMapObject *SColorMap;       /* Global colormap, NULL if nonexistent. */
+    int ImageCount;                  /* Number of current image (both APIs) */
+    GifImageDesc Image;              /* Current image (low-level API) */
+    SavedImage *SavedImages;         /* Image sequence (high-level API) */
+    int ExtensionBlockCount;         /* Count extensions past last image */
+    ExtensionBlock *ExtensionBlocks; /* Extensions past last image */    
+    int Error;			     /* Last error condition reported */
+    void *UserData;                  /* hook to attach user data (TVT) */
+    void *Private;                   /* Don't mess with this! */
+} GifFileType;
+
+#define GIF_ASPECT_RATIO(n)	((n)+15.0/64.0)
+
+typedef enum {
+    UNDEFINED_RECORD_TYPE,
+    SCREEN_DESC_RECORD_TYPE,
+    IMAGE_DESC_RECORD_TYPE, /* Begin with ',' */
+    EXTENSION_RECORD_TYPE,  /* Begin with '!' */
+    TERMINATE_RECORD_TYPE   /* Begin with ';' */
+} GifRecordType;
+
+/* func type to read gif data from arbitrary sources (TVT) */
+typedef int (*InputFunc) (GifFileType *, GifByteType *, int);
+
+/* func type to write gif data to arbitrary targets.
+ * Returns count of bytes written. (MRB)
+ */
+typedef int (*OutputFunc) (GifFileType *, const GifByteType *, int);
+
+/******************************************************************************
+ GIF89 structures
+******************************************************************************/
+
+typedef struct GraphicsControlBlock {
+    int DisposalMode;
+#define DISPOSAL_UNSPECIFIED      0       /* No disposal specified. */
+#define DISPOSE_DO_NOT            1       /* Leave image in place */
+#define DISPOSE_BACKGROUND        2       /* Set area too background color */
+#define DISPOSE_PREVIOUS          3       /* Restore to previous content */
+    bool UserInputFlag;      /* User confirmation required before disposal */
+    int DelayTime;           /* pre-display delay in 0.01sec units */
+    int TransparentColor;    /* Palette index for transparency, -1 if none */
+#define NO_TRANSPARENT_COLOR	-1
+} GraphicsControlBlock;
+
+/******************************************************************************
+ GIF encoding routines
+******************************************************************************/
+
+/* Main entry points */
+GifFileType *EGifOpenFileName(const char *GifFileName,
+                              const bool GifTestExistence, int *Error);
+GifFileType *EGifOpenFileHandle(const int GifFileHandle, int *Error);
+GifFileType *EGifOpen(void *userPtr, OutputFunc writeFunc, int *Error);
+int EGifSpew(GifFileType * GifFile);
+const char *EGifGetGifVersion(GifFileType *GifFile); /* new in 5.x */
+int EGifCloseFile(GifFileType *GifFile, int *ErrorCode);
+
+#define E_GIF_SUCCEEDED          0
+#define E_GIF_ERR_OPEN_FAILED    1    /* And EGif possible errors. */
+#define E_GIF_ERR_WRITE_FAILED   2
+#define E_GIF_ERR_HAS_SCRN_DSCR  3
+#define E_GIF_ERR_HAS_IMAG_DSCR  4
+#define E_GIF_ERR_NO_COLOR_MAP   5
+#define E_GIF_ERR_DATA_TOO_BIG   6
+#define E_GIF_ERR_NOT_ENOUGH_MEM 7
+#define E_GIF_ERR_DISK_IS_FULL   8
+#define E_GIF_ERR_CLOSE_FAILED   9
+#define E_GIF_ERR_NOT_WRITEABLE  10
+
+/* These are legacy.  You probably do not want to call them directly */
+int EGifPutScreenDesc(GifFileType *GifFile,
+                      const int GifWidth, const int GifHeight, 
+		      const int GifColorRes,
+                      const int GifBackGround,
+                      const ColorMapObject *GifColorMap);
+int EGifPutImageDesc(GifFileType *GifFile, 
+		     const int GifLeft, const int GifTop,
+                     const int GifWidth, const int GifHeight, 
+		     const bool GifInterlace,
+                     const ColorMapObject *GifColorMap);
+void EGifSetGifVersion(GifFileType *GifFile, const bool gif89);
+int EGifPutLine(GifFileType *GifFile, GifPixelType *GifLine,
+                int GifLineLen);
+int EGifPutPixel(GifFileType *GifFile, const GifPixelType GifPixel);
+int EGifPutComment(GifFileType *GifFile, const char *GifComment);
+int EGifPutExtensionLeader(GifFileType *GifFile, const int GifExtCode);
+int EGifPutExtensionBlock(GifFileType *GifFile,
+                         const int GifExtLen, const void *GifExtension);
+int EGifPutExtensionTrailer(GifFileType *GifFile);
+int EGifPutExtension(GifFileType *GifFile, const int GifExtCode, 
+		     const int GifExtLen,
+                     const void *GifExtension);
+int EGifPutCode(GifFileType *GifFile, int GifCodeSize,
+                const GifByteType *GifCodeBlock);
+int EGifPutCodeNext(GifFileType *GifFile,
+                    const GifByteType *GifCodeBlock);
+
+/******************************************************************************
+ GIF decoding routines
+******************************************************************************/
+
+/* Main entry points */
+GifFileType *DGifOpenFileName(const char *GifFileName, int *Error);
+GifFileType *DGifOpenFileHandle(int GifFileHandle, int *Error);
+int DGifSlurp(GifFileType * GifFile);
+GifFileType *DGifOpen(void *userPtr, InputFunc readFunc, int *Error);    /* new one (TVT) */
+    int DGifCloseFile(GifFileType * GifFile, int *ErrorCode);
+
+#define D_GIF_SUCCEEDED          0
+#define D_GIF_ERR_OPEN_FAILED    101    /* And DGif possible errors. */
+#define D_GIF_ERR_READ_FAILED    102
+#define D_GIF_ERR_NOT_GIF_FILE   103
+#define D_GIF_ERR_NO_SCRN_DSCR   104
+#define D_GIF_ERR_NO_IMAG_DSCR   105
+#define D_GIF_ERR_NO_COLOR_MAP   106
+#define D_GIF_ERR_WRONG_RECORD   107
+#define D_GIF_ERR_DATA_TOO_BIG   108
+#define D_GIF_ERR_NOT_ENOUGH_MEM 109
+#define D_GIF_ERR_CLOSE_FAILED   110
+#define D_GIF_ERR_NOT_READABLE   111
+#define D_GIF_ERR_IMAGE_DEFECT   112
+#define D_GIF_ERR_EOF_TOO_SOON   113
+
+/* These are legacy.  You probably do not want to call them directly */
+int DGifGetScreenDesc(GifFileType *GifFile);
+int DGifGetRecordType(GifFileType *GifFile, GifRecordType *GifType);
+int DGifGetImageDesc(GifFileType *GifFile);
+int DGifGetLine(GifFileType *GifFile, GifPixelType *GifLine, int GifLineLen);
+int DGifGetPixel(GifFileType *GifFile, GifPixelType GifPixel);
+int DGifGetComment(GifFileType *GifFile, char *GifComment);
+int DGifGetExtension(GifFileType *GifFile, int *GifExtCode,
+                     GifByteType **GifExtension);
+int DGifGetExtensionNext(GifFileType *GifFile, GifByteType **GifExtension);
+int DGifGetCode(GifFileType *GifFile, int *GifCodeSize,
+                GifByteType **GifCodeBlock);
+int DGifGetCodeNext(GifFileType *GifFile, GifByteType **GifCodeBlock);
+int DGifGetLZCodes(GifFileType *GifFile, int *GifCode);
+
+
+/******************************************************************************
+ Color table quantization (deprecated)
+******************************************************************************/
+int GifQuantizeBuffer(unsigned int Width, unsigned int Height,
+                   int *ColorMapSize, GifByteType * RedInput,
+                   GifByteType * GreenInput, GifByteType * BlueInput,
+                   GifByteType * OutputBuffer,
+                   GifColorType * OutputColorMap);
+
+/******************************************************************************
+ Error handling and reporting.
+******************************************************************************/
+extern const char *GifErrorString(int ErrorCode);     /* new in 2012 - ESR */
+
+/*****************************************************************************
+ Everything below this point is new after version 1.2, supporting `slurp
+ mode' for doing I/O in two big belts with all the image-bashing in core.
+******************************************************************************/
+
+/******************************************************************************
+ Color map handling from gif_alloc.c
+******************************************************************************/
+
+extern ColorMapObject *GifMakeMapObject(int ColorCount,
+                                     const GifColorType *ColorMap);
+extern void GifFreeMapObject(ColorMapObject *Object);
+extern ColorMapObject *GifUnionColorMap(const ColorMapObject *ColorIn1,
+                                     const ColorMapObject *ColorIn2,
+                                     GifPixelType ColorTransIn2[]);
+extern int GifBitSize(int n);
+
+extern void *
+reallocarray(void *optr, size_t nmemb, size_t size);
+
+/******************************************************************************
+ Support for the in-core structures allocation (slurp mode).              
+******************************************************************************/
+
+extern void GifApplyTranslation(SavedImage *Image, GifPixelType Translation[]);
+extern int GifAddExtensionBlock(int *ExtensionBlock_Count,
+				ExtensionBlock **ExtensionBlocks, 
+				int Function, 
+				unsigned int Len, unsigned char ExtData[]);
+extern void GifFreeExtensions(int *ExtensionBlock_Count,
+			      ExtensionBlock **ExtensionBlocks);
+extern SavedImage *GifMakeSavedImage(GifFileType *GifFile,
+                                  const SavedImage *CopyFrom);
+extern void GifFreeSavedImages(GifFileType *GifFile);
+
+/******************************************************************************
+ 5.x functions for GIF89 graphics control blocks
+******************************************************************************/
+
+int DGifExtensionToGCB(const size_t GifExtensionLength,
+		       const GifByteType *GifExtension,
+		       GraphicsControlBlock *GCB);
+size_t EGifGCBToExtension(const GraphicsControlBlock *GCB,
+		       GifByteType *GifExtension);
+
+int DGifSavedExtensionToGCB(GifFileType *GifFile, 
+			    int ImageIndex, 
+			    GraphicsControlBlock *GCB);
+int EGifGCBToSavedExtension(const GraphicsControlBlock *GCB, 
+			    GifFileType *GifFile, 
+			    int ImageIndex);
+
+/******************************************************************************
+ The library's internal utility font                          
+******************************************************************************/
+
+#define GIF_FONT_WIDTH  8
+#define GIF_FONT_HEIGHT 8
+extern const unsigned char GifAsciiTable8x8[][GIF_FONT_WIDTH];
+
+extern void GifDrawText8x8(SavedImage *Image,
+                     const int x, const int y,
+                     const char *legend, const int color);
+
+extern void GifDrawBox(SavedImage *Image,
+                    const int x, const int y,
+                    const int w, const int d, const int color);
+
+extern void GifDrawRectangle(SavedImage *Image,
+                   const int x, const int y,
+                   const int w, const int d, const int color);
+
+extern void GifDrawBoxedText8x8(SavedImage *Image,
+                          const int x, const int y,
+                          const char *legend,
+                          const int border, const int bg, const int fg);
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+#endif /* _GIF_LIB_H */
+
+/* end */
diff --git a/Src/external_dependencies/giflib/gif_lib_private.h b/Src/external_dependencies/giflib/gif_lib_private.h
new file mode 100644
index 00000000..adaf5571
--- /dev/null
+++ b/Src/external_dependencies/giflib/gif_lib_private.h
@@ -0,0 +1,59 @@
+/****************************************************************************
+
+gif_lib_private.h - internal giflib routines and structures
+
+****************************************************************************/
+
+#ifndef _GIF_LIB_PRIVATE_H
+#define _GIF_LIB_PRIVATE_H
+
+#include "gif_lib.h"
+#include "gif_hash.h"
+
+#define EXTENSION_INTRODUCER      0x21
+#define DESCRIPTOR_INTRODUCER     0x2c
+#define TERMINATOR_INTRODUCER     0x3b
+
+#define LZ_MAX_CODE         4095    /* Biggest code possible in 12 bits. */
+#define LZ_BITS             12
+
+#define FLUSH_OUTPUT        4096    /* Impossible code, to signal flush. */
+#define FIRST_CODE          4097    /* Impossible code, to signal first. */
+#define NO_SUCH_CODE        4098    /* Impossible code, to signal empty. */
+
+#define FILE_STATE_WRITE    0x01
+#define FILE_STATE_SCREEN   0x02
+#define FILE_STATE_IMAGE    0x04
+#define FILE_STATE_READ     0x08
+
+#define IS_READABLE(Private)    (Private->FileState & FILE_STATE_READ)
+#define IS_WRITEABLE(Private)   (Private->FileState & FILE_STATE_WRITE)
+
+typedef struct GifFilePrivateType {
+    GifWord FileState, FileHandle,  /* Where all this data goes to! */
+      BitsPerPixel,     /* Bits per pixel (Codes uses at least this + 1). */
+      ClearCode,   /* The CLEAR LZ code. */
+      EOFCode,     /* The EOF LZ code. */
+      RunningCode, /* The next code algorithm can generate. */
+      RunningBits, /* The number of bits required to represent RunningCode. */
+      MaxCode1,    /* 1 bigger than max. possible code, in RunningBits bits. */
+      LastCode,    /* The code before the current code. */
+      CrntCode,    /* Current algorithm code. */
+      StackPtr,    /* For character stack (see below). */
+      CrntShiftState;    /* Number of bits in CrntShiftDWord. */
+    unsigned long CrntShiftDWord;   /* For bytes decomposition into codes. */
+    unsigned long PixelCount;   /* Number of pixels in image. */
+    FILE *File;    /* File as stream. */
+    InputFunc Read;     /* function to read gif input (TVT) */
+    OutputFunc Write;   /* function to write gif output (MRB) */
+    GifByteType Buf[256];   /* Compressed input is buffered here. */
+    GifByteType Stack[LZ_MAX_CODE]; /* Decoded pixels are stacked here. */
+    GifByteType Suffix[LZ_MAX_CODE + 1];    /* So we can trace the codes. */
+    GifPrefixType Prefix[LZ_MAX_CODE + 1];
+    GifHashTableType *HashTable;
+    bool gif89;
+} GifFilePrivateType;
+
+#endif /* _GIF_LIB_PRIVATE_H */
+
+/* end */
diff --git a/Src/external_dependencies/giflib/gifalloc.c b/Src/external_dependencies/giflib/gifalloc.c
new file mode 100644
index 00000000..3b518680
--- /dev/null
+++ b/Src/external_dependencies/giflib/gifalloc.c
@@ -0,0 +1,412 @@
+/*****************************************************************************
+
+ GIF construction tools
+
+****************************************************************************/
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "gif_lib.h"
+
+#define MAX(x, y)    (((x) > (y)) ? (x) : (y))
+
+/******************************************************************************
+ Miscellaneous utility functions                          
+******************************************************************************/
+
+/* return smallest bitfield size n will fit in */
+int
+GifBitSize(int n)
+{
+    register int i;
+
+    for (i = 1; i <= 8; i++)
+        if ((1 << i) >= n)
+            break;
+    return (i);
+}
+
+/******************************************************************************
+  Color map object functions                              
+******************************************************************************/
+
+/*
+ * Allocate a color map of given size; initialize with contents of
+ * ColorMap if that pointer is non-NULL.
+ */
+ColorMapObject *
+GifMakeMapObject(int ColorCount, const GifColorType *ColorMap)
+{
+    ColorMapObject *Object;
+
+    /*** FIXME: Our ColorCount has to be a power of two.  Is it necessary to
+     * make the user know that or should we automatically round up instead? */
+    if (ColorCount != (1 << GifBitSize(ColorCount))) {
+        return ((ColorMapObject *) NULL);
+    }
+    
+    Object = (ColorMapObject *)malloc(sizeof(ColorMapObject));
+    if (Object == (ColorMapObject *) NULL) {
+        return ((ColorMapObject *) NULL);
+    }
+
+    Object->Colors = (GifColorType *)calloc(ColorCount, sizeof(GifColorType));
+    if (Object->Colors == (GifColorType *) NULL) {
+	free(Object);
+        return ((ColorMapObject *) NULL);
+    }
+
+    Object->ColorCount = ColorCount;
+    Object->BitsPerPixel = GifBitSize(ColorCount);
+    Object->SortFlag = false;
+
+    if (ColorMap != NULL) {
+        memcpy((char *)Object->Colors,
+               (char *)ColorMap, ColorCount * sizeof(GifColorType));
+    }
+
+    return (Object);
+}
+
+/*******************************************************************************
+Free a color map object
+*******************************************************************************/
+void
+GifFreeMapObject(ColorMapObject *Object)
+{
+    if (Object != NULL) {
+        (void)free(Object->Colors);
+        (void)free(Object);
+    }
+}
+
+#ifdef DEBUG
+void
+DumpColorMap(ColorMapObject *Object,
+             FILE * fp)
+{
+    if (Object != NULL) {
+        int i, j, Len = Object->ColorCount;
+
+        for (i = 0; i < Len; i += 4) {
+            for (j = 0; j < 4 && j < Len; j++) {
+                (void)fprintf(fp, "%3d: %02x %02x %02x   ", i + j,
+			      Object->Colors[i + j].Red,
+			      Object->Colors[i + j].Green,
+			      Object->Colors[i + j].Blue);
+            }
+            (void)fprintf(fp, "\n");
+        }
+    }
+}
+#endif /* DEBUG */
+
+/*******************************************************************************
+ Compute the union of two given color maps and return it.  If result can't 
+ fit into 256 colors, NULL is returned, the allocated union otherwise.
+ ColorIn1 is copied as is to ColorUnion, while colors from ColorIn2 are
+ copied iff they didn't exist before.  ColorTransIn2 maps the old
+ ColorIn2 into the ColorUnion color map table./
+*******************************************************************************/
+ColorMapObject *
+GifUnionColorMap(const ColorMapObject *ColorIn1,
+              const ColorMapObject *ColorIn2,
+              GifPixelType ColorTransIn2[])
+{
+    int i, j, CrntSlot, RoundUpTo, NewGifBitSize;
+    ColorMapObject *ColorUnion;
+
+    /*
+     * We don't worry about duplicates within either color map; if
+     * the caller wants to resolve those, he can perform unions
+     * with an empty color map.
+     */
+
+    /* Allocate table which will hold the result for sure. */
+    ColorUnion = GifMakeMapObject(MAX(ColorIn1->ColorCount,
+                               ColorIn2->ColorCount) * 2, NULL);
+
+    if (ColorUnion == NULL)
+        return (NULL);
+
+    /* 
+     * Copy ColorIn1 to ColorUnion.
+     */
+    for (i = 0; i < ColorIn1->ColorCount; i++)
+        ColorUnion->Colors[i] = ColorIn1->Colors[i];
+    CrntSlot = ColorIn1->ColorCount;
+
+    /* 
+     * Potentially obnoxious hack:
+     *
+     * Back CrntSlot down past all contiguous {0, 0, 0} slots at the end
+     * of table 1.  This is very useful if your display is limited to
+     * 16 colors.
+     */
+    while (ColorIn1->Colors[CrntSlot - 1].Red == 0
+           && ColorIn1->Colors[CrntSlot - 1].Green == 0
+           && ColorIn1->Colors[CrntSlot - 1].Blue == 0)
+        CrntSlot--;
+
+    /* Copy ColorIn2 to ColorUnion (use old colors if they exist): */
+    for (i = 0; i < ColorIn2->ColorCount && CrntSlot <= 256; i++) {
+        /* Let's see if this color already exists: */
+        for (j = 0; j < ColorIn1->ColorCount; j++)
+            if (memcmp (&ColorIn1->Colors[j], &ColorIn2->Colors[i], 
+                        sizeof(GifColorType)) == 0)
+                break;
+
+        if (j < ColorIn1->ColorCount)
+            ColorTransIn2[i] = j;    /* color exists in Color1 */
+        else {
+            /* Color is new - copy it to a new slot: */
+            ColorUnion->Colors[CrntSlot] = ColorIn2->Colors[i];
+            ColorTransIn2[i] = CrntSlot++;
+        }
+    }
+
+    if (CrntSlot > 256) {
+        GifFreeMapObject(ColorUnion);
+        return ((ColorMapObject *) NULL);
+    }
+
+    NewGifBitSize = GifBitSize(CrntSlot);
+    RoundUpTo = (1 << NewGifBitSize);
+
+    if (RoundUpTo != ColorUnion->ColorCount) {
+        register GifColorType *Map = ColorUnion->Colors;
+
+        /* 
+         * Zero out slots up to next power of 2.
+         * We know these slots exist because of the way ColorUnion's
+         * start dimension was computed.
+         */
+        for (j = CrntSlot; j < RoundUpTo; j++)
+            Map[j].Red = Map[j].Green = Map[j].Blue = 0;
+
+        /* perhaps we can shrink the map? */
+        if (RoundUpTo < ColorUnion->ColorCount) {
+            GifColorType *new_map = (GifColorType *)reallocarray(Map,
+                                 RoundUpTo, sizeof(GifColorType));
+            if( new_map == NULL ) {
+                GifFreeMapObject(ColorUnion);
+                return ((ColorMapObject *) NULL);
+            }
+            ColorUnion->Colors = new_map;
+        }
+    }
+
+    ColorUnion->ColorCount = RoundUpTo;
+    ColorUnion->BitsPerPixel = NewGifBitSize;
+
+    return (ColorUnion);
+}
+
+/*******************************************************************************
+ Apply a given color translation to the raster bits of an image
+*******************************************************************************/
+void
+GifApplyTranslation(SavedImage *Image, GifPixelType Translation[])
+{
+    register int i;
+    register int RasterSize = Image->ImageDesc.Height * Image->ImageDesc.Width;
+
+    for (i = 0; i < RasterSize; i++)
+        Image->RasterBits[i] = Translation[Image->RasterBits[i]];
+}
+
+/******************************************************************************
+ Extension record functions                              
+******************************************************************************/
+int
+GifAddExtensionBlock(int *ExtensionBlockCount,
+		     ExtensionBlock **ExtensionBlocks,
+		     int Function,
+		     unsigned int Len,
+		     unsigned char ExtData[])
+{
+    ExtensionBlock *ep;
+
+    if (*ExtensionBlocks == NULL)
+        *ExtensionBlocks=(ExtensionBlock *)malloc(sizeof(ExtensionBlock));
+    else {
+        ExtensionBlock* ep_new = (ExtensionBlock *)reallocarray
+				 (*ExtensionBlocks, (*ExtensionBlockCount + 1),
+                                      sizeof(ExtensionBlock));
+        if( ep_new == NULL )
+            return (GIF_ERROR);
+        *ExtensionBlocks = ep_new;
+    }
+
+    if (*ExtensionBlocks == NULL)
+        return (GIF_ERROR);
+
+    ep = &(*ExtensionBlocks)[(*ExtensionBlockCount)++];
+
+    ep->Function = Function;
+    ep->ByteCount=Len;
+    ep->Bytes = (GifByteType *)malloc(ep->ByteCount);
+    if (ep->Bytes == NULL)
+        return (GIF_ERROR);
+
+    if (ExtData != NULL) {
+        memcpy(ep->Bytes, ExtData, Len);
+    }
+
+    return (GIF_OK);
+}
+
+void
+GifFreeExtensions(int *ExtensionBlockCount,
+		  ExtensionBlock **ExtensionBlocks)
+{
+    ExtensionBlock *ep;
+
+    if (*ExtensionBlocks == NULL)
+        return;
+
+    for (ep = *ExtensionBlocks;
+	 ep < (*ExtensionBlocks + *ExtensionBlockCount); 
+	 ep++)
+        (void)free((char *)ep->Bytes);
+    (void)free((char *)*ExtensionBlocks);
+    *ExtensionBlocks = NULL;
+    *ExtensionBlockCount = 0;
+}
+
+/******************************************************************************
+ Image block allocation functions                          
+******************************************************************************/
+
+/* Private Function:
+ * Frees the last image in the GifFile->SavedImages array
+ */
+void
+FreeLastSavedImage(GifFileType *GifFile)
+{
+    SavedImage *sp;
+    
+    if ((GifFile == NULL) || (GifFile->SavedImages == NULL))
+        return;
+
+    /* Remove one SavedImage from the GifFile */
+    GifFile->ImageCount--;
+    sp = &GifFile->SavedImages[GifFile->ImageCount];
+
+    /* Deallocate its Colormap */
+    if (sp->ImageDesc.ColorMap != NULL) {
+        GifFreeMapObject(sp->ImageDesc.ColorMap);
+        sp->ImageDesc.ColorMap = NULL;
+    }
+
+    /* Deallocate the image data */
+    if (sp->RasterBits != NULL)
+        free((char *)sp->RasterBits);
+
+    /* Deallocate any extensions */
+    GifFreeExtensions(&sp->ExtensionBlockCount, &sp->ExtensionBlocks);
+
+    /*** FIXME: We could realloc the GifFile->SavedImages structure but is
+     * there a point to it? Saves some memory but we'd have to do it every
+     * time.  If this is used in GifFreeSavedImages then it would be inefficient
+     * (The whole array is going to be deallocated.)  If we just use it when
+     * we want to free the last Image it's convenient to do it here.
+     */
+}
+
+/*
+ * Append an image block to the SavedImages array  
+ */
+SavedImage *
+GifMakeSavedImage(GifFileType *GifFile, const SavedImage *CopyFrom)
+{
+    if (GifFile->SavedImages == NULL)
+        GifFile->SavedImages = (SavedImage *)malloc(sizeof(SavedImage));
+    else
+        GifFile->SavedImages = (SavedImage *)reallocarray(GifFile->SavedImages,
+                               (GifFile->ImageCount + 1), sizeof(SavedImage));
+
+    if (GifFile->SavedImages == NULL)
+        return ((SavedImage *)NULL);
+    else {
+        SavedImage *sp = &GifFile->SavedImages[GifFile->ImageCount++];
+        memset((char *)sp, '\0', sizeof(SavedImage));
+
+        if (CopyFrom != NULL) {
+            memcpy((char *)sp, CopyFrom, sizeof(SavedImage));
+
+            /* 
+             * Make our own allocated copies of the heap fields in the
+             * copied record.  This guards against potential aliasing
+             * problems.
+             */
+
+            /* first, the local color map */
+            if (sp->ImageDesc.ColorMap != NULL) {
+                sp->ImageDesc.ColorMap = GifMakeMapObject(
+                                         CopyFrom->ImageDesc.ColorMap->ColorCount,
+                                         CopyFrom->ImageDesc.ColorMap->Colors);
+                if (sp->ImageDesc.ColorMap == NULL) {
+                    FreeLastSavedImage(GifFile);
+                    return (SavedImage *)(NULL);
+                }
+            }
+
+            /* next, the raster */
+            sp->RasterBits = (unsigned char *)reallocarray(NULL,
+                                                  (CopyFrom->ImageDesc.Height *
+                                                  CopyFrom->ImageDesc.Width),
+						  sizeof(GifPixelType));
+            if (sp->RasterBits == NULL) {
+                FreeLastSavedImage(GifFile);
+                return (SavedImage *)(NULL);
+            }
+            memcpy(sp->RasterBits, CopyFrom->RasterBits,
+                   sizeof(GifPixelType) * CopyFrom->ImageDesc.Height *
+                   CopyFrom->ImageDesc.Width);
+
+            /* finally, the extension blocks */
+            if (sp->ExtensionBlocks != NULL) {
+                sp->ExtensionBlocks = (ExtensionBlock *)reallocarray(NULL,
+                                      CopyFrom->ExtensionBlockCount,
+				      sizeof(ExtensionBlock));
+                if (sp->ExtensionBlocks == NULL) {
+                    FreeLastSavedImage(GifFile);
+                    return (SavedImage *)(NULL);
+                }
+                memcpy(sp->ExtensionBlocks, CopyFrom->ExtensionBlocks,
+                       sizeof(ExtensionBlock) * CopyFrom->ExtensionBlockCount);
+            }
+        }
+
+        return (sp);
+    }
+}
+
+void
+GifFreeSavedImages(GifFileType *GifFile)
+{
+    SavedImage *sp;
+
+    if ((GifFile == NULL) || (GifFile->SavedImages == NULL)) {
+        return;
+    }
+    for (sp = GifFile->SavedImages;
+         sp < GifFile->SavedImages + GifFile->ImageCount; sp++) {
+        if (sp->ImageDesc.ColorMap != NULL) {
+            GifFreeMapObject(sp->ImageDesc.ColorMap);
+            sp->ImageDesc.ColorMap = NULL;
+        }
+
+        if (sp->RasterBits != NULL)
+            free((char *)sp->RasterBits);
+	
+	GifFreeExtensions(&sp->ExtensionBlockCount, &sp->ExtensionBlocks);
+    }
+    free((char *)GifFile->SavedImages);
+    GifFile->SavedImages = NULL;
+}
+
+/* end */
diff --git a/Src/external_dependencies/giflib/giflib.vcxproj b/Src/external_dependencies/giflib/giflib.vcxproj
new file mode 100644
index 00000000..08ab8fba
--- /dev/null
+++ b/Src/external_dependencies/giflib/giflib.vcxproj
@@ -0,0 +1,202 @@
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+      <OutputFile>$(OutDir)$(TargetName)$(TargetExt)</OutputFile>
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+    <ClCompile Include="dgif_lib.c" />
+    <ClCompile Include="egif_lib.c" />
+    <ClCompile Include="gifalloc.c" />
+    <ClCompile Include="gif_err.c" />
+    <ClCompile Include="gif_hash.c" />
+    <ClCompile Include="openbsd-reallocarray.c" />
+    <ClCompile Include="quantize.c" />
+  </ItemGroup>
+  <ItemGroup>
+    <ClInclude Include="gif_hash.h" />
+    <ClInclude Include="gif_lib.h" />
+    <ClInclude Include="gif_lib_private.h" />
+  </ItemGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
+  <ImportGroup Label="ExtensionTargets">
+  </ImportGroup>
+</Project>
\ No newline at end of file
diff --git a/Src/external_dependencies/giflib/giflib.vcxproj.filters b/Src/external_dependencies/giflib/giflib.vcxproj.filters
new file mode 100644
index 00000000..68bc882d
--- /dev/null
+++ b/Src/external_dependencies/giflib/giflib.vcxproj.filters
@@ -0,0 +1,48 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ItemGroup>
+    <ClCompile Include="dgif_lib.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="egif_lib.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="gif_err.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="gif_hash.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="gifalloc.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="quantize.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="openbsd-reallocarray.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+  </ItemGroup>
+  <ItemGroup>
+    <ClInclude Include="gif_hash.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
+    <ClInclude Include="gif_lib.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
+    <ClInclude Include="gif_lib_private.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
+  </ItemGroup>
+  <ItemGroup>
+    <Filter Include="Source Files">
+      <UniqueIdentifier>{7f8db09f-73c3-4ab0-9743-31078d9bdbd3}</UniqueIdentifier>
+    </Filter>
+    <Filter Include="Header Files">
+      <UniqueIdentifier>{07475227-71a0-4af5-bfa8-ec196def41e5}</UniqueIdentifier>
+    </Filter>
+    <Filter Include="Ressource Files">
+      <UniqueIdentifier>{383a58fc-e46f-4f62-a853-f78d8beeec37}</UniqueIdentifier>
+    </Filter>
+  </ItemGroup>
+</Project>
\ No newline at end of file
diff --git a/Src/external_dependencies/giflib/openbsd-reallocarray.c b/Src/external_dependencies/giflib/openbsd-reallocarray.c
new file mode 100644
index 00000000..aa706868
--- /dev/null
+++ b/Src/external_dependencies/giflib/openbsd-reallocarray.c
@@ -0,0 +1,38 @@
+/*	$OpenBSD: reallocarray.c,v 1.1 2014/05/08 21:43:49 deraadt Exp $	*/
+/*
+ * Copyright (c) 2008 Otto Moerbeek <otto@drijf.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <errno.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+/*
+ * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX
+ * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW
+ */
+#define MUL_NO_OVERFLOW	((size_t)1 << (sizeof(size_t) * 4))
+
+void *
+reallocarray(void *optr, size_t nmemb, size_t size)
+{
+	if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
+	    nmemb > 0 && SIZE_MAX / nmemb < size) {
+		errno = ENOMEM;
+		return NULL;
+	}
+	return realloc(optr, size * nmemb);
+}
diff --git a/Src/external_dependencies/giflib/quantize.c b/Src/external_dependencies/giflib/quantize.c
new file mode 100644
index 00000000..e5d4a590
--- /dev/null
+++ b/Src/external_dependencies/giflib/quantize.c
@@ -0,0 +1,330 @@
+/*****************************************************************************
+
+ quantize.c - quantize a high resolution image into lower one
+
+ Based on: "Color Image Quantization for frame buffer Display", by
+ Paul Heckbert SIGGRAPH 1982 page 297-307.
+
+ This doesn't really belong in the core library, was undocumented,
+ and was removed in 4.2.  Then it turned out some client apps were
+ actually using it, so it was restored in 5.0.
+
+******************************************************************************/
+
+#include <stdlib.h>
+#include <stdio.h>
+#include "gif_lib.h"
+#include "gif_lib_private.h"
+
+#define ABS(x)    ((x) > 0 ? (x) : (-(x)))
+
+#define COLOR_ARRAY_SIZE 32768
+#define BITS_PER_PRIM_COLOR 5
+#define MAX_PRIM_COLOR      0x1f
+
+static int SortRGBAxis;
+
+typedef struct QuantizedColorType {
+    GifByteType RGB[3];
+    GifByteType NewColorIndex;
+    long Count;
+    struct QuantizedColorType *Pnext;
+} QuantizedColorType;
+
+typedef struct NewColorMapType {
+    GifByteType RGBMin[3], RGBWidth[3];
+    unsigned int NumEntries; /* # of QuantizedColorType in linked list below */
+    unsigned long Count; /* Total number of pixels in all the entries */
+    QuantizedColorType *QuantizedColors;
+} NewColorMapType;
+
+static int SubdivColorMap(NewColorMapType * NewColorSubdiv,
+                          unsigned int ColorMapSize,
+                          unsigned int *NewColorMapSize);
+static int SortCmpRtn(const void *Entry1, const void *Entry2);
+
+/******************************************************************************
+ Quantize high resolution image into lower one. Input image consists of a
+ 2D array for each of the RGB colors with size Width by Height. There is no
+ Color map for the input. Output is a quantized image with 2D array of
+ indexes into the output color map.
+   Note input image can be 24 bits at the most (8 for red/green/blue) and
+ the output has 256 colors at the most (256 entries in the color map.).
+ ColorMapSize specifies size of color map up to 256 and will be updated to
+ real size before returning.
+   Also non of the parameter are allocated by this routine.
+   This function returns GIF_OK if successful, GIF_ERROR otherwise.
+******************************************************************************/
+int
+GifQuantizeBuffer(unsigned int Width,
+               unsigned int Height,
+               int *ColorMapSize,
+               GifByteType * RedInput,
+               GifByteType * GreenInput,
+               GifByteType * BlueInput,
+               GifByteType * OutputBuffer,
+               GifColorType * OutputColorMap) {
+
+    unsigned int Index, NumOfEntries;
+    int i, j, MaxRGBError[3];
+    unsigned int NewColorMapSize;
+    long Red, Green, Blue;
+    NewColorMapType NewColorSubdiv[256];
+    QuantizedColorType *ColorArrayEntries, *QuantizedColor;
+
+    ColorArrayEntries = (QuantizedColorType *)malloc(
+                           sizeof(QuantizedColorType) * COLOR_ARRAY_SIZE);
+    if (ColorArrayEntries == NULL) {
+        return GIF_ERROR;
+    }
+
+    for (i = 0; i < COLOR_ARRAY_SIZE; i++) {
+        ColorArrayEntries[i].RGB[0] = i >> (2 * BITS_PER_PRIM_COLOR);
+        ColorArrayEntries[i].RGB[1] = (i >> BITS_PER_PRIM_COLOR) &
+           MAX_PRIM_COLOR;
+        ColorArrayEntries[i].RGB[2] = i & MAX_PRIM_COLOR;
+        ColorArrayEntries[i].Count = 0;
+    }
+
+    /* Sample the colors and their distribution: */
+    for (i = 0; i < (int)(Width * Height); i++) {
+        Index = ((RedInput[i] >> (8 - BITS_PER_PRIM_COLOR)) <<
+                  (2 * BITS_PER_PRIM_COLOR)) +
+                ((GreenInput[i] >> (8 - BITS_PER_PRIM_COLOR)) <<
+                  BITS_PER_PRIM_COLOR) +
+                (BlueInput[i] >> (8 - BITS_PER_PRIM_COLOR));
+        ColorArrayEntries[Index].Count++;
+    }
+
+    /* Put all the colors in the first entry of the color map, and call the
+     * recursive subdivision process.  */
+    for (i = 0; i < 256; i++) {
+        NewColorSubdiv[i].QuantizedColors = NULL;
+        NewColorSubdiv[i].Count = NewColorSubdiv[i].NumEntries = 0;
+        for (j = 0; j < 3; j++) {
+            NewColorSubdiv[i].RGBMin[j] = 0;
+            NewColorSubdiv[i].RGBWidth[j] = 255;
+        }
+    }
+
+    /* Find the non empty entries in the color table and chain them: */
+    for (i = 0; i < COLOR_ARRAY_SIZE; i++)
+        if (ColorArrayEntries[i].Count > 0)
+            break;
+    QuantizedColor = NewColorSubdiv[0].QuantizedColors = &ColorArrayEntries[i];
+    NumOfEntries = 1;
+    while (++i < COLOR_ARRAY_SIZE)
+        if (ColorArrayEntries[i].Count > 0) {
+            QuantizedColor->Pnext = &ColorArrayEntries[i];
+            QuantizedColor = &ColorArrayEntries[i];
+            NumOfEntries++;
+        }
+    QuantizedColor->Pnext = NULL;
+
+    NewColorSubdiv[0].NumEntries = NumOfEntries; /* Different sampled colors */
+    NewColorSubdiv[0].Count = ((long)Width) * Height; /* Pixels */
+    NewColorMapSize = 1;
+    if (SubdivColorMap(NewColorSubdiv, *ColorMapSize, &NewColorMapSize) !=
+       GIF_OK) {
+        free((char *)ColorArrayEntries);
+        return GIF_ERROR;
+    }
+    if (NewColorMapSize < *ColorMapSize) {
+        /* And clear rest of color map: */
+        for (i = NewColorMapSize; i < *ColorMapSize; i++)
+            OutputColorMap[i].Red = OutputColorMap[i].Green =
+                OutputColorMap[i].Blue = 0;
+    }
+
+    /* Average the colors in each entry to be the color to be used in the
+     * output color map, and plug it into the output color map itself. */
+    for (i = 0; i < NewColorMapSize; i++) {
+        if ((j = NewColorSubdiv[i].NumEntries) > 0) {
+            QuantizedColor = NewColorSubdiv[i].QuantizedColors;
+            Red = Green = Blue = 0;
+            while (QuantizedColor) {
+                QuantizedColor->NewColorIndex = i;
+                Red += QuantizedColor->RGB[0];
+                Green += QuantizedColor->RGB[1];
+                Blue += QuantizedColor->RGB[2];
+                QuantizedColor = QuantizedColor->Pnext;
+            }
+            OutputColorMap[i].Red = (Red << (8 - BITS_PER_PRIM_COLOR)) / j;
+            OutputColorMap[i].Green = (Green << (8 - BITS_PER_PRIM_COLOR)) / j;
+            OutputColorMap[i].Blue = (Blue << (8 - BITS_PER_PRIM_COLOR)) / j;
+        }
+    }
+
+    /* Finally scan the input buffer again and put the mapped index in the
+     * output buffer.  */
+    MaxRGBError[0] = MaxRGBError[1] = MaxRGBError[2] = 0;
+    for (i = 0; i < (int)(Width * Height); i++) {
+        Index = ((RedInput[i] >> (8 - BITS_PER_PRIM_COLOR)) <<
+                 (2 * BITS_PER_PRIM_COLOR)) +
+                ((GreenInput[i] >> (8 - BITS_PER_PRIM_COLOR)) <<
+                 BITS_PER_PRIM_COLOR) +
+                (BlueInput[i] >> (8 - BITS_PER_PRIM_COLOR));
+        Index = ColorArrayEntries[Index].NewColorIndex;
+        OutputBuffer[i] = Index;
+        if (MaxRGBError[0] < ABS(OutputColorMap[Index].Red - RedInput[i]))
+            MaxRGBError[0] = ABS(OutputColorMap[Index].Red - RedInput[i]);
+        if (MaxRGBError[1] < ABS(OutputColorMap[Index].Green - GreenInput[i]))
+            MaxRGBError[1] = ABS(OutputColorMap[Index].Green - GreenInput[i]);
+        if (MaxRGBError[2] < ABS(OutputColorMap[Index].Blue - BlueInput[i]))
+            MaxRGBError[2] = ABS(OutputColorMap[Index].Blue - BlueInput[i]);
+    }
+
+#ifdef DEBUG
+    fprintf(stderr,
+            "Quantization L(0) errors: Red = %d, Green = %d, Blue = %d.\n",
+            MaxRGBError[0], MaxRGBError[1], MaxRGBError[2]);
+#endif /* DEBUG */
+
+    free((char *)ColorArrayEntries);
+
+    *ColorMapSize = NewColorMapSize;
+
+    return GIF_OK;
+}
+
+/******************************************************************************
+ Routine to subdivide the RGB space recursively using median cut in each
+ axes alternatingly until ColorMapSize different cubes exists.
+ The biggest cube in one dimension is subdivide unless it has only one entry.
+ Returns GIF_ERROR if failed, otherwise GIF_OK.
+*******************************************************************************/
+static int
+SubdivColorMap(NewColorMapType * NewColorSubdiv,
+               unsigned int ColorMapSize,
+               unsigned int *NewColorMapSize) {
+
+    int MaxSize;
+    unsigned int i, j, Index = 0, NumEntries, MinColor, MaxColor;
+    long Sum, Count;
+    QuantizedColorType *QuantizedColor, **SortArray;
+
+    while (ColorMapSize > *NewColorMapSize) {
+        /* Find candidate for subdivision: */
+        MaxSize = -1;
+        for (i = 0; i < *NewColorMapSize; i++) {
+            for (j = 0; j < 3; j++) {
+                if ((((int)NewColorSubdiv[i].RGBWidth[j]) > MaxSize) &&
+                      (NewColorSubdiv[i].NumEntries > 1)) {
+                    MaxSize = NewColorSubdiv[i].RGBWidth[j];
+                    Index = i;
+                    SortRGBAxis = j;
+                }
+            }
+        }
+
+        if (MaxSize == -1)
+            return GIF_OK;
+
+        /* Split the entry Index into two along the axis SortRGBAxis: */
+
+        /* Sort all elements in that entry along the given axis and split at
+         * the median.  */
+        SortArray = (QuantizedColorType **)malloc(
+                      sizeof(QuantizedColorType *) * 
+                      NewColorSubdiv[Index].NumEntries);
+        if (SortArray == NULL)
+            return GIF_ERROR;
+        for (j = 0, QuantizedColor = NewColorSubdiv[Index].QuantizedColors;
+             j < NewColorSubdiv[Index].NumEntries && QuantizedColor != NULL;
+             j++, QuantizedColor = QuantizedColor->Pnext)
+            SortArray[j] = QuantizedColor;
+
+	/*
+	 * Because qsort isn't stable, this can produce differing 
+	 * results for the order of tuples depending on platform
+	 * details of how qsort() is implemented.
+	 *
+	 * We mitigate this problem by sorting on all three axes rather
+	 * than only the one specied by SortRGBAxis; that way the instability
+	 * can only become an issue if there are multiple color indices
+	 * referring to identical RGB tuples.  Older versions of this 
+	 * sorted on only the one axis.
+	 */
+        qsort(SortArray, NewColorSubdiv[Index].NumEntries,
+              sizeof(QuantizedColorType *), SortCmpRtn);
+
+        /* Relink the sorted list into one: */
+        for (j = 0; j < NewColorSubdiv[Index].NumEntries - 1; j++)
+            SortArray[j]->Pnext = SortArray[j + 1];
+        SortArray[NewColorSubdiv[Index].NumEntries - 1]->Pnext = NULL;
+        NewColorSubdiv[Index].QuantizedColors = QuantizedColor = SortArray[0];
+        free((char *)SortArray);
+
+        /* Now simply add the Counts until we have half of the Count: */
+        Sum = NewColorSubdiv[Index].Count / 2 - QuantizedColor->Count;
+        NumEntries = 1;
+        Count = QuantizedColor->Count;
+        while (QuantizedColor->Pnext != NULL &&
+	       (Sum -= QuantizedColor->Pnext->Count) >= 0 &&
+               QuantizedColor->Pnext->Pnext != NULL) {
+            QuantizedColor = QuantizedColor->Pnext;
+            NumEntries++;
+            Count += QuantizedColor->Count;
+        }
+        /* Save the values of the last color of the first half, and first
+         * of the second half so we can update the Bounding Boxes later.
+         * Also as the colors are quantized and the BBoxes are full 0..255,
+         * they need to be rescaled.
+         */
+        MaxColor = QuantizedColor->RGB[SortRGBAxis]; /* Max. of first half */
+	/* coverity[var_deref_op] */
+        MinColor = QuantizedColor->Pnext->RGB[SortRGBAxis]; /* of second */
+        MaxColor <<= (8 - BITS_PER_PRIM_COLOR);
+        MinColor <<= (8 - BITS_PER_PRIM_COLOR);
+
+        /* Partition right here: */
+        NewColorSubdiv[*NewColorMapSize].QuantizedColors =
+           QuantizedColor->Pnext;
+        QuantizedColor->Pnext = NULL;
+        NewColorSubdiv[*NewColorMapSize].Count = Count;
+        NewColorSubdiv[Index].Count -= Count;
+        NewColorSubdiv[*NewColorMapSize].NumEntries =
+           NewColorSubdiv[Index].NumEntries - NumEntries;
+        NewColorSubdiv[Index].NumEntries = NumEntries;
+        for (j = 0; j < 3; j++) {
+            NewColorSubdiv[*NewColorMapSize].RGBMin[j] =
+               NewColorSubdiv[Index].RGBMin[j];
+            NewColorSubdiv[*NewColorMapSize].RGBWidth[j] =
+               NewColorSubdiv[Index].RGBWidth[j];
+        }
+        NewColorSubdiv[*NewColorMapSize].RGBWidth[SortRGBAxis] =
+           NewColorSubdiv[*NewColorMapSize].RGBMin[SortRGBAxis] +
+           NewColorSubdiv[*NewColorMapSize].RGBWidth[SortRGBAxis] - MinColor;
+        NewColorSubdiv[*NewColorMapSize].RGBMin[SortRGBAxis] = MinColor;
+
+        NewColorSubdiv[Index].RGBWidth[SortRGBAxis] =
+           MaxColor - NewColorSubdiv[Index].RGBMin[SortRGBAxis];
+
+        (*NewColorMapSize)++;
+    }
+
+    return GIF_OK;
+}
+
+/****************************************************************************
+ Routine called by qsort to compare two entries.
+*****************************************************************************/
+
+static int
+SortCmpRtn(const void *Entry1,
+           const void *Entry2) {
+	   QuantizedColorType *entry1 = (*((QuantizedColorType **) Entry1));
+	   QuantizedColorType *entry2 = (*((QuantizedColorType **) Entry2));
+
+	   /* sort on all axes of the color space! */
+	   int hash1 = entry1->RGB[SortRGBAxis] * 256 * 256
+	   			+ entry1->RGB[(SortRGBAxis+1) % 3] * 256
+				+ entry1->RGB[(SortRGBAxis+2) % 3];
+	   int hash2 = entry2->RGB[SortRGBAxis] * 256 * 256
+	   			+ entry2->RGB[(SortRGBAxis+1) % 3] * 256
+				+ entry2->RGB[(SortRGBAxis+2) % 3];
+
+    return hash1 - hash2;
+}
+
+/* end */