Author: kostya
Date: Thu Jul 17 07:50:30 2008
New Revision: 2809
Log:
Better scalefactor calculation
Modified:
aacenc/aacpsy.c
Modified: aacenc/aacpsy.c
==============================================================================
--- aacenc/aacpsy.c (original)
+++ aacenc/aacpsy.c Thu Jul 17 07:50:30 2008
@@ -577,16 +577,15 @@ static void psy_3gpp_process(AACPsyConte
}
//determine scalefactors - 5.6.2
- //TODO: quantization optimization, scalefactor difference reduction
for(ch = 0; ch < apc->avctx->channels; ch++){
int min_scale = 256;
prev_scale = -1;
cpe->ch[ch].gain = 0;
for(g = 0; g < apc->num_bands1024; g++){
+ cpe->ch[ch].zeroes[0][g] = pctx->band[ch][g].thr >=
pctx->band[ch][g].energy;
if(cpe->ch[ch].zeroes[0][g]) continue;
//spec gives constant for lg() but we scaled it for log2()
cpe->ch[ch].sf_idx[0][g] = (int)(2.66667 *
(log2(6.75*pctx->band[ch][g].thr) - log2(pctx->band[ch][g].ffac)));
- cpe->ch[ch].sf_idx[0][g] = av_clip(cpe->ch[ch].sf_idx[0][g], 0,
255);
if(prev_scale != -1)
cpe->ch[ch].sf_idx[0][g] = av_clip(cpe->ch[ch].sf_idx[0][g],
prev_scale - SCALE_MAX_DIFF, prev_scale + SCALE_MAX_DIFF);
prev_scale = cpe->ch[ch].sf_idx[0][g];
@@ -599,6 +598,10 @@ static void psy_3gpp_process(AACPsyConte
for(g = 0; g < apc->num_bands1024; g++){
if(cpe->ch[ch].zeroes[0][g]) continue;
cpe->ch[ch].sf_idx[0][g] = FFMIN(cpe->ch[ch].sf_idx[0][g],
min_scale + SCALE_MAX_DIFF);
+ }
+ for(g = 0; g < apc->num_bands1024; g++){
+ if(cpe->ch[ch].zeroes[0][g]) continue;
+ cpe->ch[ch].sf_idx[0][g] = SCALE_ONE_POS +
cpe->ch[ch].sf_idx[0][g];
if(!cpe->ch[ch].gain) cpe->ch[ch].gain = cpe->ch[ch].sf_idx[0][g];
}
}
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