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aacenc: Factor out find_min_book so it can be used by multiple coefficient coders.

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Originally committed as revision 23316 to svn://svn.ffmpeg.org/ffmpeg/trunk
oldabi
Alex Converse 15 years ago
parent aafb822ba5
commit 05e659ef83
1 changed files with 22 additions and 17 deletions
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  1. 39
      libavcodec/aaccoder.c

39
libavcodec/aaccoder.c
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@ -216,6 +216,27 @@ static void quantize_and_encode_band(struct AACEncContext *s, PutBitContext *pb,
INFINITY, NULL);
}
static int find_min_book(int sf, int group_len, int swb_size, const float *scaled) {
float maxval = 0.0f;
float Q = ff_aac_pow2sf_tab[200 - sf + SCALE_ONE_POS - SCALE_DIV_512];
float Q34 = sqrtf(Q * sqrtf(Q));
int qmaxval, cb, w2, i;
for (w2 = 0; w2 < group_len; w2++) {
for (i = 0; i < swb_size; i++) {
maxval = FFMAX(maxval, scaled[w2*128+i]);
}
}
qmaxval = maxval * Q34 + 0.4054f;
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;
return cb;
}
/**
* structure used in optimal codebook search
*/
@ -673,23 +694,7 @@ static void search_for_quantizers_twoloop(AVCodecContext *avctx,
{
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 = FFMAX(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;
cb = find_min_book(sce->sf_idx[w*16+g], sce->ics.group_len[w], sce->ics.swb_sizes[g], scaled);
sce->band_type[w*16+g] = cb;
for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
int b;

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