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| author | Michael Niedermayer <michaelni@gmx.at> | 2013-01-12 19:11:08 +0100 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2013-01-12 19:17:08 +0100 |
| commit | c8737d348be526d6403856f424a73ad1c81b157f (patch) | |
| tree | c870b7cbcb80791bb29c3283c5cc579b8e08a642 /libswresample | |
| parent | 93bc0f0180391dd05a5ee35d5b776ab13ac81ab9 (diff) | |
| download | ffmpeg-c8737d348be526d6403856f424a73ad1c81b157f.tar.gz | |
swr: work with 4 noise shaping coeffs at a time
63->38 kcycles
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Diffstat (limited to 'libswresample')
| -rw-r--r-- | libswresample/dither_template.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/libswresample/dither_template.c b/libswresample/dither_template.c index 8cf0c57681..ecbe55c5dd 100644 --- a/libswresample/dither_template.c +++ b/libswresample/dither_template.c @@ -29,6 +29,9 @@ void RENAME(swri_noise_shaping)(SwrContext *s, AudioData *dsts, const AudioData float S = s->dither.ns_scale; float S_1 = s->dither.ns_scale_1; + av_assert2((taps&3) != 2); + av_assert2((taps&3) != 3 || s->dither.ns_coeffs[taps] == 0); + for (ch=0; ch<srcs->ch_count; ch++) { const float *noise = ((const float *)noises->ch[ch]) + s->dither.noise_pos; const DELEM *src = (const DELEM*)srcs->ch[ch]; @@ -38,7 +41,13 @@ void RENAME(swri_noise_shaping)(SwrContext *s, AudioData *dsts, const AudioData pos = s->dither.ns_pos; for (i=0; i<count; i++) { double d1, d = src[i]*S_1; - for(j=0; j<taps; j++) + for(j=0; j<taps-2; j+=4) { + d -= ns_coeffs[j ] * ns_errors[pos + j ] + +ns_coeffs[j + 1] * ns_errors[pos + j + 1] + +ns_coeffs[j + 2] * ns_errors[pos + j + 2] + +ns_coeffs[j + 3] * ns_errors[pos + j + 3]; + } + if(j < taps) d -= ns_coeffs[j] * ns_errors[pos + j]; pos = pos ? pos - 1 : taps - 1; d1 = rint(d + noise[i]); |