It's close...
On Tue, Apr 14, 2015 at 11:17 PM, Rostislav Pehlivanov
<atomnu...@gmail.com> wrote:
> @@ -711,9 +748,11 @@ static void search_for_quantizers_twoloop(AVCodecContext
> *avctx,
> {
> int start = 0, i, w, w2, g;
> int destbits = avctx->bit_rate * 1024.0 / avctx->sample_rate /
> avctx->channels * (lambda / 120.f);
> - float dists[128] = { 0 }, uplims[128];
> + const int freq_mul = avctx->sample_rate/(1024/sce->ics.num_windows)/2;
Storing it in a const can induce a huge rounding error.
Think sample_rate 7350, 1 window. That's freq_mult = 3.588, but
rounding it will put 3, which is a huge rounding error.
Just put the whole expression when needed, that will avoid the
rounding error. Like:
> + if (s->options.pns && start*freq_mul > NOISE_LOW_LIMIT && energy
> < uplim * 1.2f) {
start*avctx->sample_rate/(1024/sce->ics.num_windows)/2 =
start*7350/1024/2 = implicitly ((start*7350)/1024)/2, avoiding the
rounding error completely.
Always consider that when doing integer math, and the possibility of
intermediate results overflowing (not possible here given the maximum
start and sample_rate).
> for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
> for (g = 0; g < sce->ics.num_swb; g++) {
> int prevsc = sce->sf_idx[w*16+g];
> + if (sce->band_type[w*16+g] == NOISE_BT) {
> + sce->sf_idx[w*16+g] = av_clip(noise_sf[w*16+g],
> minscaler_n, minscaler_n + SCALE_MAX_DIFF);
> + continue;
> + }
> if (dists[w*16+g] > uplims[w*16+g] && sce->sf_idx[w*16+g] >
> 60) {
> if (find_min_book(maxvals[w*16+g],
> sce->sf_idx[w*16+g]-1))
> sce->sf_idx[w*16+g]--;
Good, but you don't need to apply the clipping on each iteration. Do
it outside the do { ... } while (fflag && its < 10), which is just
once, at the very end.
With that fixed, I believe it will be committable.
:)
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