1 files changed, 93 insertions, 0 deletions
diff --git a/Src/mp3-mpg123/nsvmain.cpp b/Src/mp3-mpg123/nsvmain.cpp
new file mode 100644
index 00000000..539fc75e
--- /dev/null
+++ b/Src/mp3-mpg123/nsvmain.cpp
@@ -0,0 +1,93 @@
+#include "../nsv/nsvlib.h"
+#include "../nsv/dec_if.h"
+#include "nsvmain.h"
+#include "../nsutil/pcm.h"
+
+MP3_Decoder::MP3_Decoder()
+{
+	decoder = mpg123_new(NULL, NULL);
+	long flags = MPG123_QUIET|MPG123_FORCE_FLOAT|MPG123_SKIP_ID3V2|MPG123_IGNORE_STREAMLENGTH|MPG123_IGNORE_INFOFRAME;
+	mpg123_param(decoder, MPG123_FLAGS, flags, 0);
+	mpg123_param(decoder, MPG123_RVA, MPG123_RVA_OFF, 0);
+	memset(pcm_buf, 0, sizeof(pcm_buf)); 
+	mpg123_open_feed(decoder);
+	fused = 0; pcm_buf_used = 0; pcm_offs = 0; 
+}
+
+int MP3_Decoder::decode(void *in, int in_len,
+                        void *out, int *out_len,
+                        unsigned int out_fmt[8])
+{
+	int rval = 1;
+	if (fused < in_len)
+	{
+		int l = 4096;
+		if (l > in_len - fused) l = in_len - fused;
+		if (l) mpg123_feed(decoder, (unsigned char *)in + fused, l);
+		fused += l;
+	}
+
+	if (!pcm_buf_used)
+	{
+		mpg123_read(decoder, (unsigned char *)pcm_buf, sizeof(pcm_buf), &pcm_buf_used);
+		
+		pcm_offs = 0;
+	}
+
+	if (pcm_buf_used)
+	{
+		size_t numSamples = *out_len / 2;
+		if (numSamples > (pcm_buf_used/sizeof(float)))
+			numSamples = pcm_buf_used/sizeof(float);
+			nsutil_pcm_FloatToInt_Interleaved(out, pcm_buf+pcm_offs, 16, numSamples);
+		pcm_buf_used -= numSamples*sizeof(float);
+		pcm_offs += (int)numSamples;
+		*out_len = 2*(int)numSamples;
+	}
+	else
+	{
+		if (fused >= in_len) { fused = 0; rval = 0; }
+		*out_len = 0;
+	}
+	mpg123_frameinfo frameInfo;
+	if (mpg123_info(decoder, &frameInfo) == MPG123_OK) {
+		int nch = (frameInfo.mode == MPG123_M_MONO)?1:2;
+		int srate = frameInfo.rate;
+		out_fmt[0] = (nch && srate) ? NSV_MAKETYPE('P', 'C', 'M', ' ') : 0;
+		out_fmt[1] = srate;
+		out_fmt[2] = nch;
+		out_fmt[3] = (nch && srate) ? 16 : 0;
+		out_fmt[4] = frameInfo.bitrate;
+	}
+	return rval;
+}
+
+void MP3_Decoder::flush() 
+{ 
+	fused = 0; 
+	pcm_buf_used = 0;
+	pcm_offs = 0;
+	mpg123_open_feed(decoder);
+}
+
+extern "C"
+{
+	__declspec(dllexport) IAudioDecoder *CreateAudioDecoder(unsigned int fmt, IAudioOutput **output)
+	{
+		switch (fmt)
+		{
+		case NSV_MAKETYPE('M', 'P', '3', ' '):
+			return new MP3_Decoder;
+
+		default:
+			return NULL;
+		}
+	}
+
+	__declspec(dllexport) void DeleteAudioDecoder(IAudioDecoder *decoder)
+	{
+		if (decoder)
+			delete decoder;
+
+	}
+}