diff options
| author | Alex Converse <alex.converse@gmail.com> | 2008-11-05 13:59:42 +0000 |
|---|---|---|
| committer | Robert Swain <robert.swain@gmail.com> | 2008-11-05 13:59:42 +0000 |
| commit | d0ee50216d8f33f5c03a856112204cbd66009d92 (patch) | |
| tree | 685363ab2977deb47bea1a6a79609f66f4072584 /libavcodec/aac.c | |
| parent | c2dec19420e9246c8da12d7095d7fecfe98d317a (diff) | |
Fix perceptual noise shaping scaling including an oversight of the offset for
the EIGHT_SHORT window type. Fixes issue 664.
Patch by Alex Converse (alex converse gmail com)
Originally committed as revision 15776 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/aac.c')
| -rw-r--r-- | libavcodec/aac.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/libavcodec/aac.c b/libavcodec/aac.c index a207ce119f..36742bae81 100644 --- a/libavcodec/aac.c +++ b/libavcodec/aac.c @@ -399,7 +399,7 @@ static av_cold int aac_decode_init(AVCodecContext * avccontext) { } #ifndef CONFIG_HARDCODED_TABLES - for (i = 0; i < 316; i++) + for (i = 0; i < 428; i++) ff_aac_pow2sf_tab[i] = pow(2, (i - 200)/4.); #endif /* CONFIG_HARDCODED_TABLES */ @@ -573,7 +573,7 @@ static int decode_scalefactors(AACContext * ac, float sf[120], GetBitContext * g "%s (%d) out of range.\n", sf_str[1], offset[1]); return -1; } - sf[idx] = -ff_aac_pow2sf_tab[ offset[1] + sf_offset]; + sf[idx] = -ff_aac_pow2sf_tab[ offset[1] + sf_offset + 100]; } }else { for(; i < run_end; i++, idx++) { @@ -704,11 +704,17 @@ static int decode_spectrum_and_dequant(AACContext * ac, float coef[1024], GetBit memset(coef + group * 128 + offsets[i], 0, (offsets[i+1] - offsets[i])*sizeof(float)); } }else if (cur_band_type == NOISE_BT) { - const float scale = sf[idx] / ((offsets[i+1] - offsets[i]) * PNS_MEAN_ENERGY); for (group = 0; group < ics->group_len[g]; group++) { + float scale; + float band_energy = 0; for (k = offsets[i]; k < offsets[i+1]; k++) { ac->random_state = lcg_random(ac->random_state); - coef[group*128+k] = ac->random_state * scale; + coef[group*128+k] = ac->random_state; + band_energy += coef[group*128+k]*coef[group*128+k]; + } + scale = sf[idx] / sqrtf(band_energy); + for (k = offsets[i]; k < offsets[i+1]; k++) { + coef[group*128+k] *= scale; } } }else if (cur_band_type != INTENSITY_BT2 && cur_band_type != INTENSITY_BT) { |