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Diffstat (limited to 'mpg123_artsplugin/mpg123/decode_ntom.c')
-rw-r--r--mpg123_artsplugin/mpg123/decode_ntom.c290
1 files changed, 290 insertions, 0 deletions
diff --git a/mpg123_artsplugin/mpg123/decode_ntom.c b/mpg123_artsplugin/mpg123/decode_ntom.c
new file mode 100644
index 00000000..41ca0dc0
--- /dev/null
+++ b/mpg123_artsplugin/mpg123/decode_ntom.c
@@ -0,0 +1,290 @@
+/*
+ * Mpeg Layer-1,2,3 audio decoder
+ * ------------------------------
+ * copyright (c) 1995,1996,1997 by Michael Hipp, All rights reserved.
+ * See also 'README'
+ *
+ * N->M down/up sampling. Not optimized for speed.
+ */
+
+#include <stdlib.h>
+#include <math.h>
+#include <string.h>
+
+#include "mpg123.h"
+
+#define WRITE_SAMPLE(samples,sum,clip) \
+ if( (sum) > 32767.0) { *(samples) = 0x7fff; (clip)++; } \
+ else if( (sum) < -32768.0) { *(samples) = -0x8000; (clip)++; } \
+ else { *(samples) = sum; }
+
+#define NTOM_MUL (32768)
+static unsigned long ntom_val[2] = { NTOM_MUL>>1,NTOM_MUL>>1 };
+static unsigned long ntom_step = NTOM_MUL;
+
+
+void synth_ntom_set_step(long m,long n)
+{
+ if(param.verbose > 1)
+ fprintf(stderr,"Init rate converter: %ld->%ld\n",m,n);
+
+ if(n >= 96000 || m >= 96000 || m == 0 || n == 0) {
+ fprintf(stderr,"NtoM converter: illegal rates\n");
+ exit(1);
+ }
+
+ n *= NTOM_MUL;
+ ntom_step = n / m;
+
+ if(ntom_step > 8*NTOM_MUL) {
+ fprintf(stderr,"max. 1:8 conversion allowed!\n");
+ exit(1);
+ }
+
+ ntom_val[0] = ntom_val[1] = NTOM_MUL>>1;
+}
+
+int synth_ntom_8bit(real *bandPtr,int channel,unsigned char *samples,int *pnt)
+{
+ short samples_tmp[8*64];
+ short *tmp1 = samples_tmp + channel;
+ int i,ret;
+ int pnt1 = 0;
+
+ ret = synth_ntom(bandPtr,channel,(unsigned char *) samples_tmp,&pnt1);
+ samples += channel + *pnt;
+
+ for(i=0;i<(pnt1>>2);i++) {
+ *samples = conv16to8[*tmp1>>AUSHIFT];
+ samples += 2;
+ tmp1 += 2;
+ }
+ *pnt += pnt1>>1;
+
+ return ret;
+}
+
+int synth_ntom_8bit_mono(real *bandPtr,unsigned char *samples,int *pnt)
+{
+ short samples_tmp[8*64];
+ short *tmp1 = samples_tmp;
+ int i,ret;
+ int pnt1 = 0;
+
+ ret = synth_ntom(bandPtr,0,(unsigned char *) samples_tmp,&pnt1);
+ samples += *pnt;
+
+ for(i=0;i<(pnt1>>2);i++) {
+ *samples++ = conv16to8[*tmp1>>AUSHIFT];
+ tmp1 += 2;
+ }
+ *pnt += pnt1 >> 2;
+
+ return ret;
+}
+
+int synth_ntom_8bit_mono2stereo(real *bandPtr,unsigned char *samples,int *pnt)
+{
+ short samples_tmp[8*64];
+ short *tmp1 = samples_tmp;
+ int i,ret;
+ int pnt1 = 0;
+
+ ret = synth_ntom(bandPtr,0,(unsigned char *) samples_tmp,&pnt1);
+ samples += *pnt;
+
+ for(i=0;i<(pnt1>>2);i++) {
+ *samples++ = conv16to8[*tmp1>>AUSHIFT];
+ *samples++ = conv16to8[*tmp1>>AUSHIFT];
+ tmp1 += 2;
+ }
+ *pnt += pnt1 >> 1;
+
+ return ret;
+}
+
+int synth_ntom_mono(real *bandPtr,unsigned char *samples,int *pnt)
+{
+ short samples_tmp[8*64];
+ short *tmp1 = samples_tmp;
+ int i,ret;
+ int pnt1 = 0;
+
+ ret = synth_ntom(bandPtr,0,(unsigned char *) samples_tmp,&pnt1);
+ samples += *pnt;
+
+ for(i=0;i<(pnt1>>2);i++) {
+ *( (short *)samples) = *tmp1;
+ samples += 2;
+ tmp1 += 2;
+ }
+ *pnt += pnt1 >> 1;
+
+ return ret;
+}
+
+
+int synth_ntom_mono2stereo(real *bandPtr,unsigned char *samples,int *pnt)
+{
+ int i,ret;
+ int pnt1 = *pnt;
+
+ ret = synth_ntom(bandPtr,0,samples,pnt);
+ samples += pnt1;
+
+ for(i=0;i<((*pnt-pnt1)>>2);i++) {
+ ((short *)samples)[1] = ((short *)samples)[0];
+ samples+=4;
+ }
+
+ return ret;
+}
+
+
+int synth_ntom(real *bandPtr,int channel,unsigned char *out,int *pnt)
+{
+ static real buffs[2][2][0x110];
+ static const int step = 2;
+ static int bo = 1;
+ short *samples = (short *) (out + *pnt);
+
+ real *b0,(*buf)[0x110];
+ int clip = 0;
+ int bo1;
+ int ntom;
+
+#ifndef NO_EQUALIZER
+ if(param.enable_equalizer)
+ do_equalizer(bandPtr,channel);
+#endif
+
+ if(!channel) {
+ bo--;
+ bo &= 0xf;
+ buf = buffs[0];
+ ntom = ntom_val[1] = ntom_val[0];
+ }
+ else {
+ samples++;
+ out += 2; /* to compute the right *pnt value */
+ buf = buffs[1];
+ ntom = ntom_val[1];
+ }
+
+ if(bo & 0x1) {
+ b0 = buf[0];
+ bo1 = bo;
+ dct64(buf[1]+((bo+1)&0xf),buf[0]+bo,bandPtr);
+ }
+ else {
+ b0 = buf[1];
+ bo1 = bo+1;
+ dct64(buf[0]+bo,buf[1]+bo+1,bandPtr);
+ }
+
+
+ {
+ register int j;
+ real *window = decwin + 16 - bo1;
+
+ for (j=16;j;j--,window+=0x10)
+ {
+ real sum;
+
+ ntom += ntom_step;
+ if(ntom < NTOM_MUL) {
+ window += 16;
+ b0 += 16;
+ continue;
+ }
+
+ sum = *window++ * *b0++;
+ sum -= *window++ * *b0++;
+ sum += *window++ * *b0++;
+ sum -= *window++ * *b0++;
+ sum += *window++ * *b0++;
+ sum -= *window++ * *b0++;
+ sum += *window++ * *b0++;
+ sum -= *window++ * *b0++;
+ sum += *window++ * *b0++;
+ sum -= *window++ * *b0++;
+ sum += *window++ * *b0++;
+ sum -= *window++ * *b0++;
+ sum += *window++ * *b0++;
+ sum -= *window++ * *b0++;
+ sum += *window++ * *b0++;
+ sum -= *window++ * *b0++;
+
+ while(ntom >= NTOM_MUL) {
+ WRITE_SAMPLE(samples,sum,clip);
+ samples += step;
+ ntom -= NTOM_MUL;
+ }
+ }
+
+ ntom += ntom_step;
+ if(ntom >= NTOM_MUL)
+ {
+ real sum;
+ sum = window[0x0] * b0[0x0];
+ sum += window[0x2] * b0[0x2];
+ sum += window[0x4] * b0[0x4];
+ sum += window[0x6] * b0[0x6];
+ sum += window[0x8] * b0[0x8];
+ sum += window[0xA] * b0[0xA];
+ sum += window[0xC] * b0[0xC];
+ sum += window[0xE] * b0[0xE];
+
+ while(ntom >= NTOM_MUL) {
+ WRITE_SAMPLE(samples,sum,clip);
+ samples += step;
+ ntom -= NTOM_MUL;
+ }
+ }
+
+ b0-=0x10,window-=0x20;
+ window += bo1<<1;
+
+ for (j=15;j;j--,b0-=0x20,window-=0x10)
+ {
+ real sum;
+
+ ntom += ntom_step;
+ if(ntom < NTOM_MUL) {
+ window -= 16;
+ b0 += 16;
+ continue;
+ }
+
+ sum = -*(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+ sum -= *(--window) * *b0++;
+
+ while(ntom >= NTOM_MUL) {
+ WRITE_SAMPLE(samples,sum,clip);
+ samples += step;
+ ntom -= NTOM_MUL;
+ }
+ }
+ }
+
+ ntom_val[channel] = ntom;
+ *pnt = ((unsigned char *) samples - out);
+
+ return clip;
+}
+
+
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