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aaccoder: respect cutoff when marking bands as PNS 

Makes more sense as users usually set the -cutoff option
to low pass filter the signal. The encoder will still over
shoot slightly when encoding normal coefficients however
that's normal.

Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
This commit is contained in:
Rostislav Pehlivanov 2015-09-11 18:59:15 +01:00
parent abef6383fb
commit 8180b113e1
1 changed files with 2 additions and 5 deletions
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7
libavcodec/aaccoder.c
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@ -51,9 +51,6 @@
/** Frequency in Hz for lower limit of noise substitution **/
#define NOISE_LOW_LIMIT 4000
/** Pointless to substitute very high short lived inaudiable frequencies **/
#define NOISE_HIGH_LIMIT 18120
/* Parameter of f(x) = a*(lambda/100), defines the maximum fourier spread
* beyond which no PNS is used (since the SFBs contain tone rather than noise) */
#define NOISE_SPREAD_THRESHOLD 0.5073f
@ -886,7 +883,7 @@ static void search_for_pns(AACEncContext *s, AVCodecContext *avctx, SingleChanne
const int start = sce->ics.swb_offset[w*16+g];
const float freq = start*freq_mult;
const float freq_boost = FFMAX(0.88f*freq/NOISE_LOW_LIMIT, 1.0f);
if (freq < NOISE_LOW_LIMIT)
if (freq < NOISE_LOW_LIMIT || avctx->cutoff && freq >= avctx->cutoff)
continue;
for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
@ -899,7 +896,7 @@ static void search_for_pns(AACEncContext *s, AVCodecContext *avctx, SingleChanne
dist_thresh = FFMIN(2.5f*NOISE_LOW_LIMIT/freq, 1.27f);
if (sce->zeroes[w*16+g] || spread < spread_threshold ||
sfb_energy > threshold*thr_mult*freq_boost || !sfb_energy) {
sfb_energy > threshold*thr_mult*freq_boost) {
sce->pns_ener[w*16+g] = sfb_energy;
continue;
}