32 #if FF_API_AVCODEC_RESAMPLE
34 #ifndef CONFIG_RESAMPLE_HP
35 #define FILTER_SHIFT 15
38 #define FELEM2 int32_t
39 #define FELEML int64_t
40 #define FELEM_MAX INT16_MAX
41 #define FELEM_MIN INT16_MIN
43 #elif !defined(CONFIG_RESAMPLE_AUDIOPHILE_KIDDY_MODE)
44 #define FILTER_SHIFT 30
47 #define FELEM2 int64_t
48 #define FELEML int64_t
49 #define FELEM_MAX INT32_MAX
50 #define FELEM_MIN INT32_MIN
51 #define WINDOW_TYPE 12
53 #define FILTER_SHIFT 0
58 #define WINDOW_TYPE 24
62 typedef struct AVResampleContext{
71 int compensation_distance;
80 static double bessel(
double x){
87 for(i=1; v != lastv; i++){
106 const int center= (tap_count-1)/2;
115 for(ph=0;ph<phase_count;ph++) {
117 for(i=0;i<tap_count;i++) {
118 x = M_PI * ((double)(i - center) - (double)ph / phase_count) * factor;
124 x = fabs(((
double)(i - center) - (
double)ph / phase_count) * factor);
125 if(x<1.0) y= 1 - 3*x*x + 2*x*x*x + d*( -x*x + x*x*x);
126 else y= d*(-4 + 8*x - 5*x*x + x*x*x);
129 w = 2.0*x / (factor*tap_count) + M_PI;
130 y *= 0.3635819 - 0.4891775 * cos(w) + 0.1365995 * cos(2*w) - 0.0106411 * cos(3*w);
133 w = 2.0*x / (factor*tap_count*M_PI);
143 for(i=0;i<tap_count;i++) {
144 #ifdef CONFIG_RESAMPLE_AUDIOPHILE_KIDDY_MODE
145 filter[ph * tap_count + i] = tab[i] / norm;
147 filter[ph * tap_count + i] = av_clip(
lrintf(tab[i] * scale / norm), FELEM_MIN, FELEM_MAX);
155 double sine[LEN + tap_count];
156 double filtered[LEN];
157 double maxff=-2, minff=2, maxsf=-2, minsf=2;
158 for(i=0; i<LEN; i++){
159 double ss=0, sf=0, ff=0;
160 for(j=0; j<LEN+tap_count; j++)
161 sine[j]= cos(i*j*M_PI/LEN);
162 for(j=0; j<LEN; j++){
165 for(k=0; k<tap_count; k++)
166 sum += filter[ph * tap_count + k] * sine[k+j];
167 filtered[j]= sum / (1<<FILTER_SHIFT);
168 ss+= sine[j + center] * sine[j + center];
169 ff+= filtered[j] * filtered[j];
170 sf+= sine[j + center] * filtered[j];
175 maxff=
FFMAX(maxff, ff);
176 minff=
FFMIN(minff, ff);
177 maxsf=
FFMAX(maxsf, sf);
178 minsf=
FFMIN(minsf, sf);
180 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);
192 AVResampleContext *av_resample_init(
int out_rate,
int in_rate,
int filter_size,
int phase_shift,
int linear,
double cutoff){
193 AVResampleContext *c=
av_mallocz(
sizeof(AVResampleContext));
194 double factor=
FFMIN(out_rate * cutoff / in_rate, 1.0);
195 int phase_count= 1<<phase_shift;
200 c->phase_shift= phase_shift;
201 c->phase_mask= phase_count-1;
204 c->filter_length=
FFMAX((
int)ceil(filter_size/factor), 1);
205 c->filter_bank=
av_mallocz(c->filter_length*(phase_count+1)*
sizeof(
FELEM));
208 if (
build_filter(c->filter_bank, factor, c->filter_length, phase_count, 1<<FILTER_SHIFT, WINDOW_TYPE))
210 memcpy(&c->filter_bank[c->filter_length*phase_count+1], c->filter_bank, (c->filter_length-1)*
sizeof(
FELEM));
211 c->filter_bank[c->filter_length*phase_count]= c->filter_bank[c->filter_length - 1];
213 c->src_incr= out_rate;
214 c->ideal_dst_incr= c->dst_incr= in_rate * phase_count;
215 c->index= -phase_count*((c->filter_length-1)/2);
224 void av_resample_close(AVResampleContext *c){
229 void av_resample_compensate(AVResampleContext *c,
int sample_delta,
int compensation_distance){
231 c->compensation_distance= compensation_distance;
232 c->dst_incr = c->ideal_dst_incr - c->ideal_dst_incr * (int64_t)sample_delta / compensation_distance;
235 int av_resample(AVResampleContext *c,
short *dst,
short *src,
int *consumed,
int src_size,
int dst_size,
int update_ctx){
239 int dst_incr_frac= c->dst_incr % c->src_incr;
240 int dst_incr= c->dst_incr / c->src_incr;
241 int compensation_distance= c->compensation_distance;
243 if(compensation_distance == 0 && c->filter_length == 1 && c->phase_shift==0){
244 int64_t index2= ((int64_t)index)<<32;
245 int64_t incr= (1LL<<32) * c->dst_incr / c->src_incr;
246 dst_size=
FFMIN(dst_size, (src_size-1-index) * (int64_t)c->src_incr / c->dst_incr);
248 for(dst_index=0; dst_index < dst_size; dst_index++){
249 dst[dst_index] = src[index2>>32];
252 frac += dst_index * dst_incr_frac;
253 index += dst_index * dst_incr;
254 index += frac / c->src_incr;
257 for(dst_index=0; dst_index < dst_size; dst_index++){
258 FELEM *filter= c->filter_bank + c->filter_length*(index & c->phase_mask);
259 int sample_index= index >> c->phase_shift;
262 if(sample_index < 0){
263 for(i=0; i<c->filter_length; i++)
264 val += src[
FFABS(sample_index + i) % src_size] * filter[i];
265 }
else if(sample_index + c->filter_length > src_size){
269 for(i=0; i<c->filter_length; i++){
270 val += src[sample_index + i] * (
FELEM2)filter[i];
271 v2 += src[sample_index + i] * (
FELEM2)filter[i + c->filter_length];
273 val+=(v2-val)*(
FELEML)frac / c->src_incr;
275 for(i=0; i<c->filter_length; i++){
276 val += src[sample_index + i] * (
FELEM2)filter[i];
280 #ifdef CONFIG_RESAMPLE_AUDIOPHILE_KIDDY_MODE
281 dst[dst_index] = av_clip_int16(
lrintf(val));
283 val = (val + (1<<(FILTER_SHIFT-1)))>>FILTER_SHIFT;
284 dst[dst_index] = (unsigned)(val + 32768) > 65535 ? (val>>31) ^ 32767 : val;
287 frac += dst_incr_frac;
289 if(frac >= c->src_incr){
294 if(dst_index + 1 == compensation_distance){
295 compensation_distance= 0;
296 dst_incr_frac= c->ideal_dst_incr % c->src_incr;
297 dst_incr= c->ideal_dst_incr / c->src_incr;
301 *consumed=
FFMAX(index, 0) >> c->phase_shift;
302 if(index>=0) index &= c->phase_mask;
304 if(compensation_distance){
305 compensation_distance -= dst_index;
306 assert(compensation_distance > 0);
311 c->dst_incr= dst_incr_frac + c->src_incr*dst_incr;
312 c->compensation_distance= compensation_distance;
315 if(update_ctx && !c->compensation_distance){
317 av_resample_compensate(c, rand() % (8000*2) - 8000, 8000*2);
318 av_log(
NULL, AV_LOG_DEBUG,
"%d %d %d\n", c->dst_incr, c->ideal_dst_incr, c->compensation_distance);