mirror of https://git.ffmpeg.org/ffmpeg.git
312 lines
11 KiB
C
312 lines
11 KiB
C
/*
|
|
* Copyright (c) CMU 1993 Computer Science, Speech Group
|
|
* Chengxiang Lu and Alex Hauptmann
|
|
* Copyright (c) 2005 Steve Underwood <steveu at coppice.org>
|
|
* Copyright (c) 2009 Kenan Gillet
|
|
* Copyright (c) 2010 Martin Storsjo
|
|
*
|
|
* This file is part of Libav.
|
|
*
|
|
* Libav is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* Libav is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with Libav; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* G.722 ADPCM audio encoder
|
|
*/
|
|
|
|
#include "avcodec.h"
|
|
#include "g722.h"
|
|
|
|
#define FREEZE_INTERVAL 128
|
|
|
|
static av_cold int g722_encode_init(AVCodecContext * avctx)
|
|
{
|
|
G722Context *c = avctx->priv_data;
|
|
|
|
if (avctx->channels != 1) {
|
|
av_log(avctx, AV_LOG_ERROR, "Only mono tracks are allowed.\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
c->band[0].scale_factor = 8;
|
|
c->band[1].scale_factor = 2;
|
|
c->prev_samples_pos = 22;
|
|
|
|
if (avctx->trellis) {
|
|
int frontier = 1 << avctx->trellis;
|
|
int max_paths = frontier * FREEZE_INTERVAL;
|
|
int i;
|
|
for (i = 0; i < 2; i++) {
|
|
c->paths[i] = av_mallocz(max_paths * sizeof(**c->paths));
|
|
c->node_buf[i] = av_mallocz(2 * frontier * sizeof(**c->node_buf));
|
|
c->nodep_buf[i] = av_mallocz(2 * frontier * sizeof(**c->nodep_buf));
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static av_cold int g722_encode_close(AVCodecContext *avctx)
|
|
{
|
|
G722Context *c = avctx->priv_data;
|
|
int i;
|
|
for (i = 0; i < 2; i++) {
|
|
av_freep(&c->paths[i]);
|
|
av_freep(&c->node_buf[i]);
|
|
av_freep(&c->nodep_buf[i]);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static const int16_t low_quant[33] = {
|
|
35, 72, 110, 150, 190, 233, 276, 323,
|
|
370, 422, 473, 530, 587, 650, 714, 786,
|
|
858, 940, 1023, 1121, 1219, 1339, 1458, 1612,
|
|
1765, 1980, 2195, 2557, 2919
|
|
};
|
|
|
|
static inline void filter_samples(G722Context *c, const int16_t *samples,
|
|
int *xlow, int *xhigh)
|
|
{
|
|
int xout1, xout2;
|
|
c->prev_samples[c->prev_samples_pos++] = samples[0];
|
|
c->prev_samples[c->prev_samples_pos++] = samples[1];
|
|
ff_g722_apply_qmf(c->prev_samples + c->prev_samples_pos - 24, &xout1, &xout2);
|
|
*xlow = xout1 + xout2 >> 13;
|
|
*xhigh = xout1 - xout2 >> 13;
|
|
if (c->prev_samples_pos >= PREV_SAMPLES_BUF_SIZE) {
|
|
memmove(c->prev_samples,
|
|
c->prev_samples + c->prev_samples_pos - 22,
|
|
22 * sizeof(c->prev_samples[0]));
|
|
c->prev_samples_pos = 22;
|
|
}
|
|
}
|
|
|
|
static inline int encode_high(const struct G722Band *state, int xhigh)
|
|
{
|
|
int diff = av_clip_int16(xhigh - state->s_predictor);
|
|
int pred = 141 * state->scale_factor >> 8;
|
|
/* = diff >= 0 ? (diff < pred) + 2 : diff >= -pred */
|
|
return ((diff ^ (diff >> (sizeof(diff)*8-1))) < pred) + 2*(diff >= 0);
|
|
}
|
|
|
|
static inline int encode_low(const struct G722Band* state, int xlow)
|
|
{
|
|
int diff = av_clip_int16(xlow - state->s_predictor);
|
|
/* = diff >= 0 ? diff : -(diff + 1) */
|
|
int limit = diff ^ (diff >> (sizeof(diff)*8-1));
|
|
int i = 0;
|
|
limit = limit + 1 << 10;
|
|
if (limit > low_quant[8] * state->scale_factor)
|
|
i = 9;
|
|
while (i < 29 && limit > low_quant[i] * state->scale_factor)
|
|
i++;
|
|
return (diff < 0 ? (i < 2 ? 63 : 33) : 61) - i;
|
|
}
|
|
|
|
static int g722_encode_trellis(AVCodecContext *avctx,
|
|
uint8_t *dst, int buf_size, void *data)
|
|
{
|
|
G722Context *c = avctx->priv_data;
|
|
const int16_t *samples = data;
|
|
int i, j, k;
|
|
int frontier = 1 << avctx->trellis;
|
|
struct TrellisNode **nodes[2];
|
|
struct TrellisNode **nodes_next[2];
|
|
int pathn[2] = {0, 0}, froze = -1;
|
|
struct TrellisPath *p[2];
|
|
|
|
for (i = 0; i < 2; i++) {
|
|
nodes[i] = c->nodep_buf[i];
|
|
nodes_next[i] = c->nodep_buf[i] + frontier;
|
|
memset(c->nodep_buf[i], 0, 2 * frontier * sizeof(*c->nodep_buf));
|
|
nodes[i][0] = c->node_buf[i] + frontier;
|
|
nodes[i][0]->ssd = 0;
|
|
nodes[i][0]->path = 0;
|
|
nodes[i][0]->state = c->band[i];
|
|
}
|
|
|
|
for (i = 0; i < buf_size >> 1; i++) {
|
|
int xlow, xhigh;
|
|
struct TrellisNode *next[2];
|
|
int heap_pos[2] = {0, 0};
|
|
|
|
for (j = 0; j < 2; j++) {
|
|
next[j] = c->node_buf[j] + frontier*(i & 1);
|
|
memset(nodes_next[j], 0, frontier * sizeof(**nodes_next));
|
|
}
|
|
|
|
filter_samples(c, &samples[2*i], &xlow, &xhigh);
|
|
|
|
for (j = 0; j < frontier && nodes[0][j]; j++) {
|
|
/* Only k >> 2 affects the future adaptive state, therefore testing
|
|
* small steps that don't change k >> 2 is useless, the orignal
|
|
* value from encode_low is better than them. Since we step k
|
|
* in steps of 4, make sure range is a multiple of 4, so that
|
|
* we don't miss the original value from encode_low. */
|
|
int range = j < frontier/2 ? 4 : 0;
|
|
struct TrellisNode *cur_node = nodes[0][j];
|
|
|
|
int ilow = encode_low(&cur_node->state, xlow);
|
|
|
|
for (k = ilow - range; k <= ilow + range && k <= 63; k += 4) {
|
|
int decoded, dec_diff, pos;
|
|
uint32_t ssd;
|
|
struct TrellisNode* node;
|
|
|
|
if (k < 0)
|
|
continue;
|
|
|
|
decoded = av_clip((cur_node->state.scale_factor *
|
|
ff_g722_low_inv_quant6[k] >> 10)
|
|
+ cur_node->state.s_predictor, -16384, 16383);
|
|
dec_diff = xlow - decoded;
|
|
|
|
#define STORE_NODE(index, UPDATE, VALUE)\
|
|
ssd = cur_node->ssd + dec_diff*dec_diff;\
|
|
/* Check for wraparound. Using 64 bit ssd counters would \
|
|
* be simpler, but is slower on x86 32 bit. */\
|
|
if (ssd < cur_node->ssd)\
|
|
continue;\
|
|
if (heap_pos[index] < frontier) {\
|
|
pos = heap_pos[index]++;\
|
|
assert(pathn[index] < FREEZE_INTERVAL * frontier);\
|
|
node = nodes_next[index][pos] = next[index]++;\
|
|
node->path = pathn[index]++;\
|
|
} else {\
|
|
/* Try to replace one of the leaf nodes with the new \
|
|
* one, but not always testing the same leaf position */\
|
|
pos = (frontier>>1) + (heap_pos[index] & ((frontier>>1) - 1));\
|
|
if (ssd >= nodes_next[index][pos]->ssd)\
|
|
continue;\
|
|
heap_pos[index]++;\
|
|
node = nodes_next[index][pos];\
|
|
}\
|
|
node->ssd = ssd;\
|
|
node->state = cur_node->state;\
|
|
UPDATE;\
|
|
c->paths[index][node->path].value = VALUE;\
|
|
c->paths[index][node->path].prev = cur_node->path;\
|
|
/* Sift the newly inserted node up in the heap to restore \
|
|
* the heap property */\
|
|
while (pos > 0) {\
|
|
int parent = (pos - 1) >> 1;\
|
|
if (nodes_next[index][parent]->ssd <= ssd)\
|
|
break;\
|
|
FFSWAP(struct TrellisNode*, nodes_next[index][parent],\
|
|
nodes_next[index][pos]);\
|
|
pos = parent;\
|
|
}
|
|
STORE_NODE(0, ff_g722_update_low_predictor(&node->state, k >> 2), k);
|
|
}
|
|
}
|
|
|
|
for (j = 0; j < frontier && nodes[1][j]; j++) {
|
|
int ihigh;
|
|
struct TrellisNode *cur_node = nodes[1][j];
|
|
|
|
/* We don't try to get any initial guess for ihigh via
|
|
* encode_high - since there's only 4 possible values, test
|
|
* them all. Testing all of these gives a much, much larger
|
|
* gain than testing a larger range around ilow. */
|
|
for (ihigh = 0; ihigh < 4; ihigh++) {
|
|
int dhigh, decoded, dec_diff, pos;
|
|
uint32_t ssd;
|
|
struct TrellisNode* node;
|
|
|
|
dhigh = cur_node->state.scale_factor *
|
|
ff_g722_high_inv_quant[ihigh] >> 10;
|
|
decoded = av_clip(dhigh + cur_node->state.s_predictor,
|
|
-16384, 16383);
|
|
dec_diff = xhigh - decoded;
|
|
|
|
STORE_NODE(1, ff_g722_update_high_predictor(&node->state, dhigh, ihigh), ihigh);
|
|
}
|
|
}
|
|
|
|
for (j = 0; j < 2; j++) {
|
|
FFSWAP(struct TrellisNode**, nodes[j], nodes_next[j]);
|
|
|
|
if (nodes[j][0]->ssd > (1 << 16)) {
|
|
for (k = 1; k < frontier && nodes[j][k]; k++)
|
|
nodes[j][k]->ssd -= nodes[j][0]->ssd;
|
|
nodes[j][0]->ssd = 0;
|
|
}
|
|
}
|
|
|
|
if (i == froze + FREEZE_INTERVAL) {
|
|
p[0] = &c->paths[0][nodes[0][0]->path];
|
|
p[1] = &c->paths[1][nodes[1][0]->path];
|
|
for (j = i; j > froze; j--) {
|
|
dst[j] = p[1]->value << 6 | p[0]->value;
|
|
p[0] = &c->paths[0][p[0]->prev];
|
|
p[1] = &c->paths[1][p[1]->prev];
|
|
}
|
|
froze = i;
|
|
pathn[0] = pathn[1] = 0;
|
|
memset(nodes[0] + 1, 0, (frontier - 1)*sizeof(**nodes));
|
|
memset(nodes[1] + 1, 0, (frontier - 1)*sizeof(**nodes));
|
|
}
|
|
}
|
|
|
|
p[0] = &c->paths[0][nodes[0][0]->path];
|
|
p[1] = &c->paths[1][nodes[1][0]->path];
|
|
for (j = i; j > froze; j--) {
|
|
dst[j] = p[1]->value << 6 | p[0]->value;
|
|
p[0] = &c->paths[0][p[0]->prev];
|
|
p[1] = &c->paths[1][p[1]->prev];
|
|
}
|
|
c->band[0] = nodes[0][0]->state;
|
|
c->band[1] = nodes[1][0]->state;
|
|
|
|
return i;
|
|
}
|
|
|
|
static int g722_encode_frame(AVCodecContext *avctx,
|
|
uint8_t *dst, int buf_size, void *data)
|
|
{
|
|
G722Context *c = avctx->priv_data;
|
|
const int16_t *samples = data;
|
|
int i;
|
|
|
|
if (avctx->trellis)
|
|
return g722_encode_trellis(avctx, dst, buf_size, data);
|
|
|
|
for (i = 0; i < buf_size >> 1; i++) {
|
|
int xlow, xhigh, ihigh, ilow;
|
|
filter_samples(c, &samples[2*i], &xlow, &xhigh);
|
|
ihigh = encode_high(&c->band[1], xhigh);
|
|
ilow = encode_low(&c->band[0], xlow);
|
|
ff_g722_update_high_predictor(&c->band[1], c->band[1].scale_factor *
|
|
ff_g722_high_inv_quant[ihigh] >> 10, ihigh);
|
|
ff_g722_update_low_predictor(&c->band[0], ilow >> 2);
|
|
*dst++ = ihigh << 6 | ilow;
|
|
}
|
|
return i;
|
|
}
|
|
|
|
AVCodec ff_adpcm_g722_encoder = {
|
|
.name = "g722",
|
|
.type = AVMEDIA_TYPE_AUDIO,
|
|
.id = CODEC_ID_ADPCM_G722,
|
|
.priv_data_size = sizeof(G722Context),
|
|
.init = g722_encode_init,
|
|
.close = g722_encode_close,
|
|
.encode = g722_encode_frame,
|
|
.long_name = NULL_IF_CONFIG_SMALL("G.722 ADPCM"),
|
|
.sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE},
|
|
};
|