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Code Issues Releases Activity

aacenc: Use an estimated codebook for the TLS (two loop search).

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Originally committed as revision 23134 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Alex Converse 2010-05-14 16:49:30 +00:00
parent 960323a230
commit 51cbabc792
1 changed files with 18 additions and 3 deletions
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21
libavcodec/aaccoder.c
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@ -604,9 +604,26 @@ static void search_for_quantizers_twoloop(AVCodecContext *avctx,
continue;
}
minscaler = FFMIN(minscaler, sce->sf_idx[w*16+g]);
for (cb = 0; cb <= ESC_BT; cb++) {
{
float dist = 0.0f;
int bb = 0;
float maxval = 0.0f;
float Q = ff_aac_pow2sf_tab[200 - sce->sf_idx[w*16+g] + SCALE_ONE_POS - SCALE_DIV_512];
float Q34 = sqrtf(Q * sqrtf(Q));
int qmaxval;
for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
for (i = 0; i < sce->ics.swb_sizes[g]; i++) {
maxval = fmaxf(maxval, scaled[w2*128+i]);
}
}
qmaxval = maxval * Q34 + 0.4054;
if (qmaxval == 0) cb = 0;
else if (qmaxval == 1) cb = 1;
else if (qmaxval == 2) cb = 3;
else if (qmaxval <= 4) cb = 5;
else if (qmaxval <= 7) cb = 7;
else if (qmaxval <= 12) cb = 9;
else cb = 11;
for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
int b;
dist += quantize_band_cost(s, coefs + w2*128,
@ -619,10 +636,8 @@ static void search_for_quantizers_twoloop(AVCodecContext *avctx,
&b);
bb += b;
}
if (dist < mindist) {
mindist = dist;
minbits = bb;
}
}
dists[w*16+g] = (mindist - minbits) / lambda;
bits = minbits;