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-rw-r--r--src/pcm_utils.c56
1 files changed, 22 insertions, 34 deletions
diff --git a/src/pcm_utils.c b/src/pcm_utils.c
index ba387a4b1..e0ebf2ecb 100644
--- a/src/pcm_utils.c
+++ b/src/pcm_utils.c
@@ -218,41 +218,29 @@ void pcm_convertAudioFormat(AudioFormat * inFormat, char * inBuffer, size_t
}
else {
/* only works if outFormat is 16-bit stereo! */
- /* resampling code blatantly ripped from XMMS */
- const int shift = sizeof(mpd_sint16);
- int x1 = 0, frac;
- mpd_sint32 i, in_samples, out_samples, x, delta;
- mpd_sint16 * inptr = (mpd_sint16 *)dataChannelConv;
- mpd_sint16 * outptr = (mpd_sint16 *)outBuffer;
- mpd_uint32 nlen = (((dataChannelLen >> shift) *
- (outFormat->sampleRate)) /
+ /* resampling code blatantly ripped from ESD */
+ mpd_sint32 rd_dat = 0;
+ mpd_uint32 wr_dat = 0;
+ mpd_sint16 lsample, rsample;
+ register mpd_sint16 * out = (mpd_sint16 *)outBuffer;
+ register mpd_sint16 * in = (mpd_sint16 *)dataChannelConv;
+ const int shift = sizeof(mpd_sint16);
+ mpd_uint32 nlen = ((( dataChannelLen >> shift) *
+ (mpd_uint32)(outFormat->sampleRate)) /
inFormat->sampleRate);
- nlen <<= shift;
- in_samples = dataChannelLen >> shift;
- out_samples = nlen >> shift;
- //printf("in_samples=%i out_samples=%i\n",in_samples,out_samples);
- delta = ((in_samples-1) << 12) / (out_samples-1);
- for(x = 0, i = 0; i < out_samples; i++) {
- //int i1,i2,i3,i4;
- x1 = (x >> 12) << 12;
- frac = x - x1;
- /* i1 = (x1 >> 12) << 1;
- i2 = ((x1 >> 12) + 1) << 1;
- i3 = ((x1 >> 12) << 1) + 1;
- i4 = (((x1 >> 12) + 1) << 1) + 1;
- printf("%i,%i,%i,%i\n",i1,i2,i3,i4);*/
- *outptr++ =
- ((inptr[(x1 >> 12) << 1] *
- ((1<<12) - frac) +
- inptr[((x1 >> 12) + 1) << 1 ] *
- frac) >> 12);
- *outptr++ =
- ((inptr[((x1 >> 12) << 1) + 1] *
- ((1<<12) - frac) +
- inptr[(((x1 >> 12) + 1) << 1) + 1] *
- frac) >> 12);
- x += delta;
- }
+ nlen <<= shift;
+
+ while( wr_dat < nlen / shift) {
+ rd_dat = wr_dat * inFormat->sampleRate /
+ outFormat->sampleRate;
+ rd_dat &= ~1;
+
+ lsample = in[ rd_dat++ ];
+ rsample = in[ rd_dat++ ];
+
+ out[ wr_dat++ ] = lsample;
+ out[ wr_dat++ ] = rsample;
+ }
}
return;