MrBesen
/
ffmpeg
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

swr: generate more dither noise to improve quality. 

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2012-04-11 13:26:32 +02:00
parent 22057e8ecb
commit 1fc4ff2205
2 changed files with 9 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
libswresample/swresample.c
View File

@ -519,18 +519,22 @@ static int swr_convert_internal(struct SwrContext *s, AudioData *out, int out_co
if(preout != out && out_count){
if(s->dither_method){
int ch;
int dither_count= FFMAX(out_count, 1<<16);
av_assert0(preout != in);
if((ret=realloc_audio(&s->dither, out_count))<0)
if((ret=realloc_audio(&s->dither, dither_count))<0)
return ret;
if(ret)
for(ch=0; ch<s->dither.ch_count; ch++)
swri_get_dither(s->dither.ch[ch], s->dither.count, 12345678913579<<ch, s->out_sample_fmt, s->int_sample_fmt, s->dither_method);
av_assert0(s->dither.ch_count == preout->ch_count);
for(ch=0; ch<preout->ch_count; ch++){
swri_sum2(s->int_sample_fmt, preout->ch[ch], preout->ch[ch], s->dither.ch[ch], 1, 1, out_count);
}
if(s->dither_pos + out_count > s->dither.count)
s->dither_pos = 0;
for(ch=0; ch<preout->ch_count; ch++)
swri_sum2(s->int_sample_fmt, preout->ch[ch], preout->ch[ch], s->dither.ch[ch] + s->dither.bps * s->dither_pos, 1, 1, out_count);
s->dither_pos += out_count;
}
//FIXME packed doesnt need more than 1 chan here!
swri_audio_convert(s->out_convert, out, preout, out_count);

1
libswresample/swresample_internal.h
View File

@ -50,6 +50,7 @@ struct SwrContext {
const int *channel_map; ///< channel index (or -1 if muted channel) map
int used_ch_count; ///< number of used input channels (mapped channel count if channel_map, otherwise in.ch_count)
enum SwrDitherType dither_method;
int dither_pos;
int int_bps; ///< internal bytes per sample
int resample_first; ///< 1 if resampling must come first, 0 if rematrixing