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-rw-r--r--mp3lib/layer1.c157
-rw-r--r--mp3lib/sr1.c10
2 files changed, 162 insertions, 5 deletions
diff --git a/mp3lib/layer1.c b/mp3lib/layer1.c
new file mode 100644
index 0000000000..4af0933823
--- /dev/null
+++ b/mp3lib/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"
+
+static 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(4);
+ *ba++ = getbits(4);
+ }
+ for (i=jsbound;i<SBLIMIT;i++)
+ *ba++ = getbits(4);
+
+ ba = balloc;
+
+ for (i=0;i<jsbound;i++) {
+ if ((*ba++))
+ *sca++ = getbits(6);
+ if ((*ba++))
+ *sca++ = getbits(6);
+ }
+ for (i=jsbound;i<SBLIMIT;i++)
+ if ((*ba++)) {
+ *sca++ = getbits(6);
+ *sca++ = getbits(6);
+ }
+ }
+ else {
+ int i;
+ for (i=0;i<SBLIMIT;i++)
+ *ba++ = getbits(4);
+ ba = balloc;
+ for (i=0;i<SBLIMIT;i++)
+ if ((*ba++))
+ *sca++ = getbits(6);
+ }
+}
+
+static 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(n+1);
+ if ((n = *ba++))
+ *sample++ = getbits(n+1);
+ }
+ for (i=jsbound;i<SBLIMIT;i++)
+ if ((n = *ba++))
+ *sample++ = getbits(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(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;
+ }
+}
+
+static int do_layer1(struct frame *fr,int single)
+{
+ 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;
+
+// printf("do_layer1(0x%02X 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X )\n",
+// wordpointer[0],wordpointer[1],wordpointer[2],wordpointer[3],wordpointer[4],wordpointer[5],wordpointer[6],wordpointer[7]);
+
+ 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);
+ }
+
+ }
+
+ return clip;
+}
+
+
diff --git a/mp3lib/sr1.c b/mp3lib/sr1.c
index cdd07bcdd0..760b95ce68 100644
--- a/mp3lib/sr1.c
+++ b/mp3lib/sr1.c
@@ -271,8 +271,9 @@ switch(fr->lay){
MP3_samplerate=freqs[fr->sampling_frequency];
fr->framesize = (long) MP3_bitrate * 12000;
fr->framesize /= MP3_samplerate;
- MP3_framesize = fr->framesize;
- fr->framesize = ((fr->framesize+fr->padding)<<2)-4;
+ MP3_framesize = ((fr->framesize+fr->padding)<<2);
+ fr->framesize = MP3_framesize-4;
+ printf("framesize=%d\n",fr->framesize);
break;
default:
MP3_framesize=fr->framesize=0;
@@ -375,6 +376,7 @@ int _has_mmx = 0; // used by layer2.c, layer3.c to pre-scale coeffs
#include "layer2.c"
#include "layer3.c"
+#include "layer1.c"
/******************************************************************************/
/* PUBLIC FUNCTIONS */
@@ -516,9 +518,7 @@ int MP3_DecodeFrame(unsigned char *hova,short single){
switch(fr.lay){
case 2: do_layer2(&fr,single);break;
case 3: do_layer3(&fr,single);break;
- case 1:
- printf("mp3lib: layer-1 audio not yet supported!\n");
- return 4608;
+ case 1: do_layer1(&fr,single);break;
default:
return 0; // unsupported
}