ffmpeg | branch: master | Lynne <d...@lynne.ee> | Wed Jun 12 03:20:56 2024 +0200| [11a8e0a4e585c0a5acf09397e39bccf45e1ba7ae] | committer: Lynne
aacdec_usac: dequantize scalefactors after noise synthesis The issue here is that the spec implied that the offset is done on the dequantized scalefactor, but in fact, it is done on the scalefactor offset. Delay dequantizing the scalefactors until after noise synthesis is performed, and change to apply the offset onto the offset. > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=11a8e0a4e585c0a5acf09397e39bccf45e1ba7ae --- libavcodec/aac/aacdec_usac.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/libavcodec/aac/aacdec_usac.c b/libavcodec/aac/aacdec_usac.c index aa89b83182..100203ff71 100644 --- a/libavcodec/aac/aacdec_usac.c +++ b/libavcodec/aac/aacdec_usac.c @@ -971,7 +971,7 @@ static void apply_noise_fill(AACDecContext *ac, SingleChannelElement *sce, } if (band_quantized_to_zero) - sce->sf[g*ics->max_sfb + sfb] += noise_offset; + sce->sfo[g*ics->max_sfb + sfb] += noise_offset; } coef += g_len << 7; } @@ -987,6 +987,9 @@ static void spectrum_scale(AACDecContext *ac, SingleChannelElement *sce, if (ue->noise.level) apply_noise_fill(ac, sce, ue); + /* Noise filling may apply an offset to the scalefactor offset */ + ac->dsp.dequant_scalefactors(sce); + /* Apply scalefactors */ coef = sce->coeffs; for (int g = 0; g < ics->num_window_groups; g++) { @@ -1371,8 +1374,6 @@ static int decode_usac_core_coder(AACDecContext *ac, AACUSACConfig *usac, if (ret < 0) return ret; - ac->dsp.dequant_scalefactors(sce); - if (ue->tns_data_present) { sce->tns.present = 1; ret = ff_aac_decode_tns(ac, &sce->tns, gb, ics); _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog To unsubscribe, visit link above, or email ffmpeg-cvslog-requ...@ffmpeg.org with subject "unsubscribe".
