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Diffstat (limited to 'contrib/ffmpeg/libavcodec/resample2.c')
-rw-r--r--contrib/ffmpeg/libavcodec/resample2.c88
1 files changed, 70 insertions, 18 deletions
diff --git a/contrib/ffmpeg/libavcodec/resample2.c b/contrib/ffmpeg/libavcodec/resample2.c
index 3ae0ba855..4209b9705 100644
--- a/contrib/ffmpeg/libavcodec/resample2.c
+++ b/contrib/ffmpeg/libavcodec/resample2.c
@@ -30,20 +30,31 @@
#include "common.h"
#include "dsputil.h"
-#if 1
+#ifndef CONFIG_RESAMPLE_HP
#define FILTER_SHIFT 15
#define FELEM int16_t
#define FELEM2 int32_t
+#define FELEML int64_t
#define FELEM_MAX INT16_MAX
#define FELEM_MIN INT16_MIN
-#else
-#define FILTER_SHIFT 22
+#define WINDOW_TYPE 9
+#elif !defined(CONFIG_RESAMPLE_AUDIOPHILE_KIDDY_MODE)
+#define FILTER_SHIFT 30
#define FELEM int32_t
#define FELEM2 int64_t
+#define FELEML int64_t
#define FELEM_MAX INT32_MAX
#define FELEM_MIN INT32_MIN
+#define WINDOW_TYPE 12
+#else
+#define FILTER_SHIFT 0
+
+#define FELEM double
+#define FELEM2 double
+#define FELEML double
+#define WINDOW_TYPE 24
#endif
@@ -69,9 +80,10 @@ static double bessel(double x){
double t=1;
int i;
+ x= x*x/4;
for(i=1; i<50; i++){
- t *= i;
- v += pow(x*x/4, i)/(t*t);
+ t *= x/(i*i);
+ v += t;
}
return v;
}
@@ -80,7 +92,7 @@ static double bessel(double x){
* builds a polyphase filterbank.
* @param factor resampling factor
* @param scale wanted sum of coefficients for each filter
- * @param type 0->cubic, 1->blackman nuttall windowed sinc, 2->kaiser windowed sinc beta=16
+ * @param type 0->cubic, 1->blackman nuttall windowed sinc, 2..16->kaiser windowed sinc beta=2..16
*/
void av_build_filter(FELEM *filter, double factor, int tap_count, int phase_count, int scale, int type){
int ph, i, v;
@@ -93,7 +105,6 @@ void av_build_filter(FELEM *filter, double factor, int tap_count, int phase_coun
for(ph=0;ph<phase_count;ph++) {
double norm = 0;
- double e= 0;
for(i=0;i<tap_count;i++) {
x = M_PI * ((double)(i - center) - (double)ph / phase_count) * factor;
if (x == 0) y = 1.0;
@@ -109,9 +120,9 @@ void av_build_filter(FELEM *filter, double factor, int tap_count, int phase_coun
w = 2.0*x / (factor*tap_count) + M_PI;
y *= 0.3635819 - 0.4891775 * cos(w) + 0.1365995 * cos(2*w) - 0.0106411 * cos(3*w);
break;
- case 2:
+ default:
w = 2.0*x / (factor*tap_count*M_PI);
- y *= bessel(16*sqrt(FFMAX(1-w*w, 0)));
+ y *= bessel(type*sqrt(FFMAX(1-w*w, 0)));
break;
}
@@ -121,11 +132,49 @@ void av_build_filter(FELEM *filter, double factor, int tap_count, int phase_coun
/* normalize so that an uniform color remains the same */
for(i=0;i<tap_count;i++) {
- v = clip(lrintf(tab[i] * scale / norm + e), FELEM_MIN, FELEM_MAX);
- filter[ph * tap_count + i] = v;
- e += tab[i] * scale / norm - v;
+#ifdef CONFIG_RESAMPLE_AUDIOPHILE_KIDDY_MODE
+ filter[ph * tap_count + i] = tab[i] / norm;
+#else
+ filter[ph * tap_count + i] = av_clip(lrintf(tab[i] * scale / norm), FELEM_MIN, FELEM_MAX);
+#endif
+ }
+ }
+#if 0
+ {
+#define LEN 1024
+ int j,k;
+ double sine[LEN + tap_count];
+ double filtered[LEN];
+ double maxff=-2, minff=2, maxsf=-2, minsf=2;
+ for(i=0; i<LEN; i++){
+ double ss=0, sf=0, ff=0;
+ for(j=0; j<LEN+tap_count; j++)
+ sine[j]= cos(i*j*M_PI/LEN);
+ for(j=0; j<LEN; j++){
+ double sum=0;
+ ph=0;
+ for(k=0; k<tap_count; k++)
+ sum += filter[ph * tap_count + k] * sine[k+j];
+ filtered[j]= sum / (1<<FILTER_SHIFT);
+ ss+= sine[j + center] * sine[j + center];
+ ff+= filtered[j] * filtered[j];
+ sf+= sine[j + center] * filtered[j];
+ }
+ ss= sqrt(2*ss/LEN);
+ ff= sqrt(2*ff/LEN);
+ sf= 2*sf/LEN;
+ maxff= FFMAX(maxff, ff);
+ minff= FFMIN(minff, ff);
+ maxsf= FFMAX(maxsf, sf);
+ minsf= FFMIN(minsf, sf);
+ if(i%11==0){
+ av_log(NULL, AV_LOG_ERROR, "i:%4d ss:%f ff:%13.6e-%13.6e sf:%13.6e-%13.6e\n", i, ss, maxff, minff, maxsf, minsf);
+ minff=minsf= 2;
+ maxff=maxsf= -2;
+ }
}
}
+#endif
}
/**
@@ -143,7 +192,7 @@ AVResampleContext *av_resample_init(int out_rate, int in_rate, int filter_size,
c->filter_length= FFMAX((int)ceil(filter_size/factor), 1);
c->filter_bank= av_mallocz(c->filter_length*(phase_count+1)*sizeof(FELEM));
- av_build_filter(c->filter_bank, factor, c->filter_length, phase_count, 1<<FILTER_SHIFT, 1);
+ av_build_filter(c->filter_bank, factor, c->filter_length, phase_count, 1<<FILTER_SHIFT, WINDOW_TYPE);
memcpy(&c->filter_bank[c->filter_length*phase_count+1], c->filter_bank, (c->filter_length-1)*sizeof(FELEM));
c->filter_bank[c->filter_length*phase_count]= c->filter_bank[c->filter_length - 1];
@@ -219,21 +268,24 @@ int av_resample(AVResampleContext *c, short *dst, short *src, int *consumed, int
}else if(sample_index + c->filter_length > src_size){
break;
}else if(c->linear){
- int64_t v=0;
- int sub_phase= (frac<<8) / c->src_incr;
+ FELEM2 v2=0;
for(i=0; i<c->filter_length; i++){
- int64_t coeff= filter[i]*(256 - sub_phase) + filter[i + c->filter_length]*sub_phase;
- v += src[sample_index + i] * coeff;
+ val += src[sample_index + i] * (FELEM2)filter[i];
+ v2 += src[sample_index + i] * (FELEM2)filter[i + c->filter_length];
}
- val= v>>8;
+ val+=(v2-val)*(FELEML)frac / c->src_incr;
}else{
for(i=0; i<c->filter_length; i++){
val += src[sample_index + i] * (FELEM2)filter[i];
}
}
+#ifdef CONFIG_RESAMPLE_AUDIOPHILE_KIDDY_MODE
+ dst[dst_index] = av_clip(lrintf(val), -32768, 32767);
+#else
val = (val + (1<<(FILTER_SHIFT-1)))>>FILTER_SHIFT;
dst[dst_index] = (unsigned)(val + 32768) > 65535 ? (val>>31) ^ 32767 : val;
+#endif
frac += dst_incr_frac;
index += dst_incr;
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-26 20:15:23 +0000