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| author | Claudio Freire <klaussfreire@gmail.com> | 2016-01-08 05:31:32 -0300 |
|---|---|---|
| committer | Claudio Freire <klaussfreire@gmail.com> | 2016-01-13 05:28:34 -0300 |
| commit | 6711aa21e263a270ecd2d6a6ee1b673e665ce98a (patch) | |
| tree | 0dabd389dc37350c7fe3c632fd73f558f984cc95 /libavcodec/aaccoder.c | |
| parent | 4dcb69cc12d00d46f93a07178e2087a8d27c8f64 (diff) | |
| download | ffmpeg-6711aa21e263a270ecd2d6a6ee1b673e665ce98a.tar.gz | |
AAC encoder: various fixes in M/S coding
1. Fix sf_idx and band_type addressing to address only the first
subwindow in the group (others could hold garbage values)
2. Don't step on ms_mask when is_mask is set. I/S selection
already sets the ms_mask properly and shouldn't be overridden.
3. Use mid/sid cb/sf when computing coding error, as should be
since those are the cb/sfs that will eventually be set.
4. Fix distortion computation on multi-subwindow groups (was
subtracting the bits terms multiple times)
5. Clear ms_mask when one side uses PNS and the other doesn't.
When using PNS, ms_mask signals correlated noise, which can be
detected just like regular M/S detection, so we don't skip
noise bands, but when only one side uses PNS setting the flag
can confuse some encoders, so avoid that.
Diffstat (limited to 'libavcodec/aaccoder.c')
| -rw-r--r-- | libavcodec/aaccoder.c | 33 |
1 files changed, 18 insertions, 15 deletions
diff --git a/libavcodec/aaccoder.c b/libavcodec/aaccoder.c index 2c125fd080..bf515c21c1 100644 --- a/libavcodec/aaccoder.c +++ b/libavcodec/aaccoder.c @@ -831,8 +831,9 @@ static void search_for_ms(AACEncContext *s, ChannelElement *cpe) start = 0; for (g = 0; g < sce0->ics.num_swb; g++) { float bmax = bval2bmax(g * 17.0f / sce0->ics.num_swb) / 0.0045f; - cpe->ms_mask[w*16+g] = 0; - if (!sce0->zeroes[w*16+g] && !sce1->zeroes[w*16+g]) { + if (!cpe->is_mask[w*16+g]) + cpe->ms_mask[w*16+g] = 0; + if (!sce0->zeroes[w*16+g] && !sce1->zeroes[w*16+g] && !cpe->is_mask[w*16+g]) { float Mmax = 0.0f, Smax = 0.0f; /* Must compute mid/side SF and book for the whole window group */ @@ -861,7 +862,7 @@ static void search_for_ms(AACEncContext *s, ChannelElement *cpe) minidx = FFMIN(sce0->sf_idx[w*16+g], sce1->sf_idx[w*16+g]); mididx = av_clip(minidx, 0, SCALE_MAX_POS - SCALE_DIV_512); sididx = av_clip(minidx - sid_sf_boost * 3, 0, SCALE_MAX_POS - SCALE_DIV_512); - if (!cpe->is_mask[w*16+g] && sce0->band_type[w*16+g] != NOISE_BT && sce1->band_type[w*16+g] != NOISE_BT + if (sce0->band_type[w*16+g] != NOISE_BT && sce1->band_type[w*16+g] != NOISE_BT && ( !ff_sfdelta_can_replace(sce0, nextband0, prev_mid, mididx, w*16+g) || !ff_sfdelta_can_replace(sce1, nextband1, prev_side, sididx, w*16+g))) { /* scalefactor range violation, bad stuff, will decrease quality unacceptably */ @@ -894,40 +895,42 @@ static void search_for_ms(AACEncContext *s, ChannelElement *cpe) dist1 += quantize_band_cost(s, &sce0->coeffs[start + (w+w2)*128], L34, sce0->ics.swb_sizes[g], - sce0->sf_idx[(w+w2)*16+g], - sce0->band_type[(w+w2)*16+g], + sce0->sf_idx[w*16+g], + sce0->band_type[w*16+g], lambda / band0->threshold, INFINITY, &b1, NULL, 0); dist1 += quantize_band_cost(s, &sce1->coeffs[start + (w+w2)*128], R34, sce1->ics.swb_sizes[g], - sce1->sf_idx[(w+w2)*16+g], - sce1->band_type[(w+w2)*16+g], + sce1->sf_idx[w*16+g], + sce1->band_type[w*16+g], lambda / band1->threshold, INFINITY, &b2, NULL, 0); dist2 += quantize_band_cost(s, M, M34, sce0->ics.swb_sizes[g], - sce0->sf_idx[(w+w2)*16+g], - sce0->band_type[(w+w2)*16+g], + mididx, + midcb, lambda / minthr, INFINITY, &b3, NULL, 0); dist2 += quantize_band_cost(s, S, S34, sce1->ics.swb_sizes[g], - sce1->sf_idx[(w+w2)*16+g], - sce1->band_type[(w+w2)*16+g], + sididx, + sidcb, mslambda / (minthr * bmax), INFINITY, &b4, NULL, 0); B0 += b1+b2; B1 += b3+b4; - dist1 -= B0; - dist2 -= B1; + dist1 -= b1+b2; + dist2 -= b3+b4; } cpe->ms_mask[w*16+g] = dist2 <= dist1 && B1 < B0; if (cpe->ms_mask[w*16+g]) { - /* Setting the M/S mask is useful with I/S or PNS, but only the flag */ - if (!cpe->is_mask[w*16+g] && sce0->band_type[w*16+g] != NOISE_BT && sce1->band_type[w*16+g] != NOISE_BT) { + if (sce0->band_type[w*16+g] != NOISE_BT && sce1->band_type[w*16+g] != NOISE_BT) { sce0->sf_idx[w*16+g] = mididx; sce1->sf_idx[w*16+g] = sididx; sce0->band_type[w*16+g] = midcb; sce1->band_type[w*16+g] = sidcb; + } else if ((sce0->band_type[w*16+g] != NOISE_BT) ^ (sce1->band_type[w*16+g] != NOISE_BT)) { + /* ms_mask unneeded, and it confuses some decoders */ + cpe->ms_mask[w*16+g] = 0; } break; } else if (B1 > B0) { |