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authortoma <toma@283d02a7-25f6-0310-bc7c-ecb5cbfe19da>2009-11-25 17:56:58 +0000
committertoma <toma@283d02a7-25f6-0310-bc7c-ecb5cbfe19da>2009-11-25 17:56:58 +0000
commite2de64d6f1beb9e492daf5b886e19933c1fa41dd (patch)
tree9047cf9e6b5c43878d5bf82660adae77ceee097a /mpg123_artsplugin/mpg123/layer1.c
downloadtdemultimedia-e2de64d6f1beb9e492daf5b886e19933c1fa41dd.tar.gz
tdemultimedia-e2de64d6f1beb9e492daf5b886e19933c1fa41dd.zip
Copy the KDE 3.5 branch to branches/trinity for new KDE 3.5 features.
BUG:215923 git-svn-id: svn://anonsvn.kde.org/home/kde/branches/trinity/kdemultimedia@1054174 283d02a7-25f6-0310-bc7c-ecb5cbfe19da
Diffstat (limited to 'mpg123_artsplugin/mpg123/layer1.c')
-rw-r--r--mpg123_artsplugin/mpg123/layer1.c157
1 files changed, 157 insertions, 0 deletions
diff --git a/mpg123_artsplugin/mpg123/layer1.c b/mpg123_artsplugin/mpg123/layer1.c
new file mode 100644
index 00000000..a33335ab
--- /dev/null
+++ b/mpg123_artsplugin/mpg123/layer1.c
@@ -0,0 +1,157 @@
+/*
+ * Mpeg Layer-1 audio decoder
+ * --------------------------
+ * copyright (c) 1995 by Michael Hipp, All rights reserved. See also 'README'
+ * near unoptimzed ...
+ *
+ * may have a few bugs after last optimization ...
+ *
+ */
+
+#include "mpg123.h"
+
+#include "getbits.h"
+
+void I_step_one(unsigned int balloc[], unsigned int scale_index[2][SBLIMIT],struct frame *fr)
+{
+ unsigned int *ba=balloc;
+ unsigned int *sca = (unsigned int *) scale_index;
+
+ if(fr->stereo) {
+ int i;
+ int jsbound = fr->jsbound;
+ for (i=0;i<jsbound;i++) {
+ *ba++ = getbits(&bsi,4);
+ *ba++ = getbits(&bsi,4);
+ }
+ for (i=jsbound;i<SBLIMIT;i++)
+ *ba++ = getbits(&bsi,4);
+
+ ba = balloc;
+
+ for (i=0;i<jsbound;i++) {
+ if ((*ba++))
+ *sca++ = getbits(&bsi,6);
+ if ((*ba++))
+ *sca++ = getbits(&bsi,6);
+ }
+ for (i=jsbound;i<SBLIMIT;i++)
+ if ((*ba++)) {
+ *sca++ = getbits(&bsi,6);
+ *sca++ = getbits(&bsi,6);
+ }
+ }
+ else {
+ int i;
+ for (i=0;i<SBLIMIT;i++)
+ *ba++ = getbits(&bsi,4);
+ ba = balloc;
+ for (i=0;i<SBLIMIT;i++)
+ if ((*ba++))
+ *sca++ = getbits(&bsi,6);
+ }
+}
+
+void I_step_two(real fraction[2][SBLIMIT],unsigned int balloc[2*SBLIMIT],
+ unsigned int scale_index[2][SBLIMIT],struct frame *fr)
+{
+ int i,n;
+ int smpb[2*SBLIMIT]; /* values: 0-65535 */
+ int *sample;
+ register unsigned int *ba;
+ register unsigned int *sca = (unsigned int *) scale_index;
+
+ if(fr->stereo) {
+ int jsbound = fr->jsbound;
+ register real *f0 = fraction[0];
+ register real *f1 = fraction[1];
+ ba = balloc;
+ for (sample=smpb,i=0;i<jsbound;i++) {
+ if ((n = *ba++))
+ *sample++ = getbits(&bsi,n+1);
+ if ((n = *ba++))
+ *sample++ = getbits(&bsi,n+1);
+ }
+ for (i=jsbound;i<SBLIMIT;i++)
+ if ((n = *ba++))
+ *sample++ = getbits(&bsi,n+1);
+
+ ba = balloc;
+ for (sample=smpb,i=0;i<jsbound;i++) {
+ if((n=*ba++))
+ *f0++ = (real) ( ((-1)<<n) + (*sample++) + 1) * muls[n+1][*sca++];
+ else
+ *f0++ = 0.0;
+ if((n=*ba++))
+ *f1++ = (real) ( ((-1)<<n) + (*sample++) + 1) * muls[n+1][*sca++];
+ else
+ *f1++ = 0.0;
+ }
+ for (i=jsbound;i<SBLIMIT;i++) {
+ if ((n=*ba++)) {
+ real samp = ( ((-1)<<n) + (*sample++) + 1);
+ *f0++ = samp * muls[n+1][*sca++];
+ *f1++ = samp * muls[n+1][*sca++];
+ }
+ else
+ *f0++ = *f1++ = 0.0;
+ }
+ for(i=fr->down_sample_sblimit;i<32;i++)
+ fraction[0][i] = fraction[1][i] = 0.0;
+ }
+ else {
+ register real *f0 = fraction[0];
+ ba = balloc;
+ for (sample=smpb,i=0;i<SBLIMIT;i++)
+ if ((n = *ba++))
+ *sample++ = getbits(&bsi,n+1);
+ ba = balloc;
+ for (sample=smpb,i=0;i<SBLIMIT;i++) {
+ if((n=*ba++))
+ *f0++ = (real) ( ((-1)<<n) + (*sample++) + 1) * muls[n+1][*sca++];
+ else
+ *f0++ = 0.0;
+ }
+ for(i=fr->down_sample_sblimit;i<32;i++)
+ fraction[0][i] = 0.0;
+ }
+}
+
+int do_layer1(struct mpstr *mp,struct frame *fr,int outmode,struct audio_info_struct *ai)
+{
+ int clip=0;
+ int i,stereo = fr->stereo;
+ unsigned int balloc[2*SBLIMIT];
+ unsigned int scale_index[2][SBLIMIT];
+ real fraction[2][SBLIMIT];
+ int single = fr->single;
+
+ fr->jsbound = (fr->mode == MPG_MD_JOINT_STEREO) ? (fr->mode_ext<<2)+4 : 32;
+
+ if(stereo == 1 || single == 3)
+ single = 0;
+
+ I_step_one(balloc,scale_index,fr);
+
+ for (i=0;i<SCALE_BLOCK;i++)
+ {
+ I_step_two(fraction,balloc,scale_index,fr);
+
+ if(single >= 0)
+ {
+ clip += (fr->synth_mono)( (real *) fraction[single],pcm_sample,&pcm_point);
+ }
+ else {
+ int p1 = pcm_point;
+ clip += (fr->synth)( (real *) fraction[0],0,pcm_sample,&p1);
+ clip += (fr->synth)( (real *) fraction[1],1,pcm_sample,&pcm_point);
+ }
+
+ if(pcm_point >= audiobufsize)
+ audio_flush(outmode,ai);
+ }
+
+ return clip;
+}
+
+