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opus: simplify coarse energy beta coefficients 

Just put the subtraction in the table.

Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
This commit is contained in:
Rostislav Pehlivanov 2017-07-18 20:47:30 +01:00
parent 9b93795890
commit 79450adfc8
3 changed files with 14 additions and 18 deletions
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24
libavcodec/opus_celt.c
View File

@ -29,25 +29,21 @@
#include "opustab.h"
#include "opus_pvq.h"
/* Use the 2D z-transform to apply prediction in both the time domain (alpha)
* and the frequency domain (beta) */
static void celt_decode_coarse_energy(CeltFrame *f, OpusRangeCoder *rc)
{
int i, j;
float prev[2] = {0};
float alpha, beta;
const uint8_t *model;
float prev[2] = { 0 };
float alpha = ff_celt_alpha_coef[f->size];
float beta = ff_celt_beta_coef[f->size];
const uint8_t *model = ff_celt_coarse_energy_dist[f->size][0];
/* use the 2D z-transform to apply prediction in both */
/* the time domain (alpha) and the frequency domain (beta) */
if (opus_rc_tell(rc)+3 <= f->framebits && ff_opus_rc_dec_log(rc, 3)) {
/* intra frame */
alpha = 0;
beta = 1.0f - 4915.0f/32768.0f;
/* intra frame */
if (opus_rc_tell(rc) + 3 <= f->framebits && ff_opus_rc_dec_log(rc, 3)) {
alpha = 0.0f;
beta = 1.0f - (4915.0f/32768.0f);
model = ff_celt_coarse_energy_dist[f->size][1];
} else {
alpha = ff_celt_alpha_coef[f->size];
beta = 1.0f - ff_celt_beta_coef[f->size];
model = ff_celt_coarse_energy_dist[f->size][0];
}
for (i = 0; i < CELT_MAX_BANDS; i++) {

4
libavcodec/opusenc.c
View File

@ -644,10 +644,10 @@ static void exp_quant_coarse(OpusRangeCoder *rc, CeltFrame *f,
if (intra) {
alpha = 0.0f;
beta = 1.0f - 4915.0f/32768.0f;
beta = 1.0f - (4915.0f/32768.0f);
} else {
alpha = ff_celt_alpha_coef[f->size];
beta = 1.0f - ff_celt_beta_coef[f->size];
beta = ff_celt_beta_coef[f->size];
}
for (i = f->start_band; i < f->end_band; i++) {

4
libavcodec/opustab.c
View File

@ -796,8 +796,8 @@ const float ff_celt_alpha_coef[] = {
29440.0f/32768.0f, 26112.0f/32768.0f, 21248.0f/32768.0f, 16384.0f/32768.0f
};
const float ff_celt_beta_coef[] = { /* TODO: precompute 1 minus this if the code ends up neater */
30147.0f/32768.0f, 22282.0f/32768.0f, 12124.0f/32768.0f, 6554.0f/32768.0f
const float ff_celt_beta_coef[] = {
1.0f - (30147.0f/32768.0f), 1.0f - (22282.0f/32768.0f), 1.0f - (12124.0f/32768.0f), 1.0f - (6554.0f/32768.0f),
};
const uint8_t ff_celt_coarse_energy_dist[4][2][42] = {