1 files changed, 139 insertions, 0 deletions
diff --git a/Src/Winamp/SABuffer.cpp b/Src/Winamp/SABuffer.cpp
new file mode 100644
index 00000000..dfe47c6c
--- /dev/null
+++ b/Src/Winamp/SABuffer.cpp
@@ -0,0 +1,139 @@
+#include "SABuffer.h"
+#include "fft.h"
+#include "../nsutil/window.h"
+#include <windows.h>
+
+static const float const_1_div_128_ = 1.0f / 128.0f;  /* 8 bit multiplier */
+static const float const_1_div_32768_ = 1.0f / 32768.f; /* 16 bit multiplier */
+static const double const_1_div_2147483648_ = 1.0 / 2147483648.0; /* 32 bit multiplier */
+
+static void Int16_To_Float32(float *dest, void *sourceBuffer, signed int sourceStride, unsigned int count)
+{
+	signed short *src = (signed short*)sourceBuffer;
+
+	while (count--)
+	{
+		float samp = *src * const_1_div_32768_; /* FIXME: i'm concerned about this being asymetrical with float->int16 -rb */
+		*dest = samp;
+
+		src += sourceStride;
+		dest++;
+	}
+}
+
+static void Int24_To_Float32(float *dest, void *sourceBuffer, signed int sourceStride, unsigned int count)
+{
+	unsigned char *src = (unsigned char*)sourceBuffer;
+
+	while (count--)
+	{
+		signed long temp = (((long)src[0]) << 8);
+		temp = temp | (((long)src[1]) << 16);
+		temp = temp | (((long)src[2]) << 24);
+
+		*dest = (float)((double)temp * const_1_div_2147483648_);
+
+		src += sourceStride * 3;
+		dest++;
+	}
+}
+
+static void Int32_To_Float32(float *dest, void *sourceBuffer, signed int sourceStride, unsigned int count)
+{
+	int32_t *src = (int32_t *)sourceBuffer;
+
+	while (count--)
+	{
+		*dest = (float)((double)*src * const_1_div_2147483648_);
+
+		src += sourceStride;
+		dest++;
+	}
+}
+
+static void UInt8_To_Float32(float *dest, void *sourceBuffer, signed int sourceStride, unsigned int count)
+{
+	unsigned char *src = (unsigned char*)sourceBuffer;
+
+	while (count--)
+	{
+		float samp = (*src - 128) * const_1_div_128_;
+		*dest = samp;
+
+		src += sourceStride;
+		dest++;
+	}
+}
+
+SABuffer::SABuffer()
+{
+	memset(&buffer, 0, sizeof(buffer));
+	used=0;
+	init=false;
+}
+
+void SABuffer::CopyHalf()
+{
+	memcpy(buffer[0], buffer[0]+SABUFFER_WINDOW_INCREMENT, (512-SABUFFER_WINDOW_INCREMENT)*sizeof(float));
+	memcpy(buffer[1], buffer[1]+SABUFFER_WINDOW_INCREMENT, (512-SABUFFER_WINDOW_INCREMENT)*sizeof(float));
+	used-=SABUFFER_WINDOW_INCREMENT;
+}
+
+void SABuffer::Clear()
+{
+	used=0;
+}
+
+void SABuffer::WindowToFFTBuffer(float *wavetrum)
+{
+	for (int i=0;i<512;i++)
+	{
+		wavetrum[i] = (buffer[0][i] + buffer[1][i]);
+		//*wavetrum++=0;
+	}
+	nsutil_window_Multiply_F32_IP(wavetrum, window, 512);
+}
+
+unsigned int SABuffer::AddToBuffer(char *samples, int numChannels, int bps, int ts, unsigned int numSamples)
+{
+	if (!init) {
+		nsutil_window_FillHann_F32_IP(window, 512); // TODO this could be hardcoded
+		init=true;
+	}
+
+	unsigned int toCopy = min((unsigned int)(512-used), numSamples);
+	switch (bps)
+	{
+	case 8:
+		UInt8_To_Float32(buffer[0]+used, samples, numChannels, toCopy);
+		if (numChannels > 1)
+			UInt8_To_Float32(buffer[1]+used, samples+1, numChannels, toCopy);
+		else
+			UInt8_To_Float32(buffer[1]+used, samples, numChannels, toCopy);
+		break;
+	case 16:
+		Int16_To_Float32(buffer[0]+used, samples, numChannels, toCopy);
+		if (numChannels > 1)
+			Int16_To_Float32(buffer[1]+used, samples+2, numChannels, toCopy);
+		else
+			Int16_To_Float32(buffer[1]+used, samples, numChannels, toCopy);
+		break;
+	case 24:
+		Int24_To_Float32(buffer[0]+used, samples, numChannels, toCopy);
+		if (numChannels > 1)
+			Int24_To_Float32(buffer[1]+used, samples+3, numChannels, toCopy);
+		else
+			Int24_To_Float32(buffer[1]+used, samples, numChannels, toCopy);
+		break;
+	case 32:
+		Int32_To_Float32(buffer[0]+used, samples, numChannels, toCopy);
+		if (numChannels > 1)
+			Int32_To_Float32(buffer[1]+used, samples+4, numChannels, toCopy);
+		else
+			Int32_To_Float32(buffer[1]+used, samples, numChannels, toCopy);
+		break;
+	}
+	used+=toCopy;
+	return toCopy;
+}
+