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FFmpeg/libavcodec/nellymoserenc.c
Anton Khirnov 2df0c32ea1 lavc: use a separate field for exporting audio encoder padding
Currently, the amount of padding inserted at the beginning by some audio
encoders, is exported through AVCodecContext.delay. However
- the term 'delay' is heavily overloaded and can have multiple different
  meanings even in the case of audio encoding.
- this field has entirely different meanings, depending on whether the
  codec context is used for encoding or decoding (and has yet another
  different meaning for video), preventing generic handling of the codec
  context.

Therefore, add a new field -- AVCodecContext.initial_padding. It could
conceivably be used for decoding as well at a later point.
2014-10-13 19:09:01 +00:00

422 lines
14 KiB
C

/*
* Nellymoser encoder
* This code is developed as part of Google Summer of Code 2008 Program.
*
* Copyright (c) 2008 Bartlomiej Wolowiec
*
* 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
* Nellymoser encoder
* by Bartlomiej Wolowiec
*
* Generic codec information: libavcodec/nellymoserdec.c
*
* Some information also from: http://samples.libav.org/A-codecs/Nelly_Moser/ASAO/ASAO.zip
* (Copyright Joseph Artsimovich and UAB "DKD")
*
* for more information about nellymoser format, visit:
* http://wiki.multimedia.cx/index.php?title=Nellymoser
*/
#include "libavutil/common.h"
#include "libavutil/float_dsp.h"
#include "libavutil/mathematics.h"
#include "audio_frame_queue.h"
#include "avcodec.h"
#include "fft.h"
#include "internal.h"
#include "nellymoser.h"
#include "sinewin.h"
#define BITSTREAM_WRITER_LE
#include "put_bits.h"
#define POW_TABLE_SIZE (1<<11)
#define POW_TABLE_OFFSET 3
#define OPT_SIZE ((1<<15) + 3000)
typedef struct NellyMoserEncodeContext {
AVCodecContext *avctx;
int last_frame;
AVFloatDSPContext fdsp;
FFTContext mdct_ctx;
AudioFrameQueue afq;
DECLARE_ALIGNED(32, float, mdct_out)[NELLY_SAMPLES];
DECLARE_ALIGNED(32, float, in_buff)[NELLY_SAMPLES];
DECLARE_ALIGNED(32, float, buf)[3 * NELLY_BUF_LEN]; ///< sample buffer
float (*opt )[NELLY_BANDS];
uint8_t (*path)[NELLY_BANDS];
} NellyMoserEncodeContext;
static float pow_table[POW_TABLE_SIZE]; ///< -pow(2, -i / 2048.0 - 3.0);
static const uint8_t sf_lut[96] = {
0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 4, 4,
5, 5, 5, 6, 7, 7, 8, 8, 9, 10, 11, 11, 12, 13, 13, 14,
15, 15, 16, 17, 17, 18, 19, 19, 20, 21, 22, 22, 23, 24, 25, 26,
27, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40,
41, 41, 42, 43, 44, 45, 45, 46, 47, 48, 49, 50, 51, 52, 52, 53,
54, 55, 55, 56, 57, 57, 58, 59, 59, 60, 60, 60, 61, 61, 61, 62,
};
static const uint8_t sf_delta_lut[78] = {
0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 4, 4,
4, 5, 5, 5, 6, 6, 7, 7, 8, 8, 9, 10, 10, 11, 11, 12,
13, 13, 14, 15, 16, 17, 17, 18, 19, 19, 20, 21, 21, 22, 22, 23,
23, 24, 24, 25, 25, 25, 26, 26, 26, 26, 27, 27, 27, 27, 27, 28,
28, 28, 28, 28, 28, 29, 29, 29, 29, 29, 29, 29, 29, 30,
};
static const uint8_t quant_lut[230] = {
0,
0, 1, 2,
0, 1, 2, 3, 4, 5, 6,
0, 1, 1, 2, 2, 3, 3, 4, 5, 6, 7, 8, 9, 10, 11, 11,
12, 13, 13, 13, 14,
0, 1, 1, 2, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 8,
8, 9, 10, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,
22, 23, 23, 24, 24, 25, 25, 26, 26, 27, 27, 28, 28, 29, 29, 29,
30,
0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 3,
4, 4, 4, 5, 5, 5, 6, 6, 7, 7, 7, 8, 8, 9, 9, 9,
10, 10, 11, 11, 11, 12, 12, 13, 13, 13, 13, 14, 14, 14, 15, 15,
15, 15, 16, 16, 16, 17, 17, 17, 18, 18, 18, 19, 19, 20, 20, 20,
21, 21, 22, 22, 23, 23, 24, 25, 26, 26, 27, 28, 29, 30, 31, 32,
33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 42, 43, 44, 44, 45, 45,
46, 47, 47, 48, 48, 49, 49, 50, 50, 50, 51, 51, 51, 52, 52, 52,
53, 53, 53, 54, 54, 54, 55, 55, 55, 56, 56, 56, 57, 57, 57, 57,
58, 58, 58, 58, 59, 59, 59, 59, 60, 60, 60, 60, 60, 61, 61, 61,
61, 61, 61, 61, 62,
};
static const float quant_lut_mul[7] = { 0.0, 0.0, 2.0, 2.0, 5.0, 12.0, 36.6 };
static const float quant_lut_add[7] = { 0.0, 0.0, 2.0, 7.0, 21.0, 56.0, 157.0 };
static const uint8_t quant_lut_offset[8] = { 0, 0, 1, 4, 11, 32, 81, 230 };
static void apply_mdct(NellyMoserEncodeContext *s)
{
float *in0 = s->buf;
float *in1 = s->buf + NELLY_BUF_LEN;
float *in2 = s->buf + 2 * NELLY_BUF_LEN;
s->fdsp.vector_fmul (s->in_buff, in0, ff_sine_128, NELLY_BUF_LEN);
s->fdsp.vector_fmul_reverse(s->in_buff + NELLY_BUF_LEN, in1, ff_sine_128, NELLY_BUF_LEN);
s->mdct_ctx.mdct_calc(&s->mdct_ctx, s->mdct_out, s->in_buff);
s->fdsp.vector_fmul (s->in_buff, in1, ff_sine_128, NELLY_BUF_LEN);
s->fdsp.vector_fmul_reverse(s->in_buff + NELLY_BUF_LEN, in2, ff_sine_128, NELLY_BUF_LEN);
s->mdct_ctx.mdct_calc(&s->mdct_ctx, s->mdct_out + NELLY_BUF_LEN, s->in_buff);
}
static av_cold int encode_end(AVCodecContext *avctx)
{
NellyMoserEncodeContext *s = avctx->priv_data;
ff_mdct_end(&s->mdct_ctx);
if (s->avctx->trellis) {
av_free(s->opt);
av_free(s->path);
}
ff_af_queue_close(&s->afq);
return 0;
}
static av_cold int encode_init(AVCodecContext *avctx)
{
NellyMoserEncodeContext *s = avctx->priv_data;
int i, ret;
if (avctx->channels != 1) {
av_log(avctx, AV_LOG_ERROR, "Nellymoser supports only 1 channel\n");
return AVERROR(EINVAL);
}
if (avctx->sample_rate != 8000 && avctx->sample_rate != 16000 &&
avctx->sample_rate != 11025 &&
avctx->sample_rate != 22050 && avctx->sample_rate != 44100 &&
avctx->strict_std_compliance >= FF_COMPLIANCE_NORMAL) {
av_log(avctx, AV_LOG_ERROR, "Nellymoser works only with 8000, 16000, 11025, 22050 and 44100 sample rate\n");
return AVERROR(EINVAL);
}
avctx->frame_size = NELLY_SAMPLES;
avctx->initial_padding = NELLY_BUF_LEN;
ff_af_queue_init(avctx, &s->afq);
s->avctx = avctx;
if ((ret = ff_mdct_init(&s->mdct_ctx, 8, 0, 32768.0)) < 0)
goto error;
avpriv_float_dsp_init(&s->fdsp, avctx->flags & CODEC_FLAG_BITEXACT);
/* Generate overlap window */
ff_sine_window_init(ff_sine_128, 128);
for (i = 0; i < POW_TABLE_SIZE; i++)
pow_table[i] = -pow(2, -i / 2048.0 - 3.0 + POW_TABLE_OFFSET);
if (s->avctx->trellis) {
s->opt = av_malloc(NELLY_BANDS * OPT_SIZE * sizeof(float ));
s->path = av_malloc(NELLY_BANDS * OPT_SIZE * sizeof(uint8_t));
if (!s->opt || !s->path) {
ret = AVERROR(ENOMEM);
goto error;
}
}
return 0;
error:
encode_end(avctx);
return ret;
}
#define find_best(val, table, LUT, LUT_add, LUT_size) \
best_idx = \
LUT[av_clip ((lrintf(val) >> 8) + LUT_add, 0, LUT_size - 1)]; \
if (fabs(val - table[best_idx]) > fabs(val - table[best_idx + 1])) \
best_idx++;
static void get_exponent_greedy(NellyMoserEncodeContext *s, float *cand, int *idx_table)
{
int band, best_idx, power_idx = 0;
float power_candidate;
//base exponent
find_best(cand[0], ff_nelly_init_table, sf_lut, -20, 96);
idx_table[0] = best_idx;
power_idx = ff_nelly_init_table[best_idx];
for (band = 1; band < NELLY_BANDS; band++) {
power_candidate = cand[band] - power_idx;
find_best(power_candidate, ff_nelly_delta_table, sf_delta_lut, 37, 78);
idx_table[band] = best_idx;
power_idx += ff_nelly_delta_table[best_idx];
}
}
static inline float distance(float x, float y, int band)
{
//return pow(fabs(x-y), 2.0);
float tmp = x - y;
return tmp * tmp;
}
static void get_exponent_dynamic(NellyMoserEncodeContext *s, float *cand, int *idx_table)
{
int i, j, band, best_idx;
float power_candidate, best_val;
float (*opt )[NELLY_BANDS] = s->opt ;
uint8_t(*path)[NELLY_BANDS] = s->path;
for (i = 0; i < NELLY_BANDS * OPT_SIZE; i++) {
opt[0][i] = INFINITY;
}
for (i = 0; i < 64; i++) {
opt[0][ff_nelly_init_table[i]] = distance(cand[0], ff_nelly_init_table[i], 0);
path[0][ff_nelly_init_table[i]] = i;
}
for (band = 1; band < NELLY_BANDS; band++) {
int q, c = 0;
float tmp;
int idx_min, idx_max, idx;
power_candidate = cand[band];
for (q = 1000; !c && q < OPT_SIZE; q <<= 2) {
idx_min = FFMAX(0, cand[band] - q);
idx_max = FFMIN(OPT_SIZE, cand[band - 1] + q);
for (i = FFMAX(0, cand[band - 1] - q); i < FFMIN(OPT_SIZE, cand[band - 1] + q); i++) {
if ( isinf(opt[band - 1][i]) )
continue;
for (j = 0; j < 32; j++) {
idx = i + ff_nelly_delta_table[j];
if (idx > idx_max)
break;
if (idx >= idx_min) {
tmp = opt[band - 1][i] + distance(idx, power_candidate, band);
if (opt[band][idx] > tmp) {
opt[band][idx] = tmp;
path[band][idx] = j;
c = 1;
}
}
}
}
}
assert(c); //FIXME
}
best_val = INFINITY;
best_idx = -1;
band = NELLY_BANDS - 1;
for (i = 0; i < OPT_SIZE; i++) {
if (best_val > opt[band][i]) {
best_val = opt[band][i];
best_idx = i;
}
}
for (band = NELLY_BANDS - 1; band >= 0; band--) {
idx_table[band] = path[band][best_idx];
if (band) {
best_idx -= ff_nelly_delta_table[path[band][best_idx]];
}
}
}
/**
* Encode NELLY_SAMPLES samples. It assumes, that samples contains 3 * NELLY_BUF_LEN values
* @param s encoder context
* @param output output buffer
* @param output_size size of output buffer
*/
static void encode_block(NellyMoserEncodeContext *s, unsigned char *output, int output_size)
{
PutBitContext pb;
int i, j, band, block, best_idx, power_idx = 0;
float power_val, coeff, coeff_sum;
float pows[NELLY_FILL_LEN];
int bits[NELLY_BUF_LEN], idx_table[NELLY_BANDS];
float cand[NELLY_BANDS];
apply_mdct(s);
init_put_bits(&pb, output, output_size * 8);
i = 0;
for (band = 0; band < NELLY_BANDS; band++) {
coeff_sum = 0;
for (j = 0; j < ff_nelly_band_sizes_table[band]; i++, j++) {
coeff_sum += s->mdct_out[i ] * s->mdct_out[i ]
+ s->mdct_out[i + NELLY_BUF_LEN] * s->mdct_out[i + NELLY_BUF_LEN];
}
cand[band] =
log(FFMAX(1.0, coeff_sum / (ff_nelly_band_sizes_table[band] << 7))) * 1024.0 / M_LN2;
}
if (s->avctx->trellis) {
get_exponent_dynamic(s, cand, idx_table);
} else {
get_exponent_greedy(s, cand, idx_table);
}
i = 0;
for (band = 0; band < NELLY_BANDS; band++) {
if (band) {
power_idx += ff_nelly_delta_table[idx_table[band]];
put_bits(&pb, 5, idx_table[band]);
} else {
power_idx = ff_nelly_init_table[idx_table[0]];
put_bits(&pb, 6, idx_table[0]);
}
power_val = pow_table[power_idx & 0x7FF] / (1 << ((power_idx >> 11) + POW_TABLE_OFFSET));
for (j = 0; j < ff_nelly_band_sizes_table[band]; i++, j++) {
s->mdct_out[i] *= power_val;
s->mdct_out[i + NELLY_BUF_LEN] *= power_val;
pows[i] = power_idx;
}
}
ff_nelly_get_sample_bits(pows, bits);
for (block = 0; block < 2; block++) {
for (i = 0; i < NELLY_FILL_LEN; i++) {
if (bits[i] > 0) {
const float *table = ff_nelly_dequantization_table + (1 << bits[i]) - 1;
coeff = s->mdct_out[block * NELLY_BUF_LEN + i];
best_idx =
quant_lut[av_clip (
coeff * quant_lut_mul[bits[i]] + quant_lut_add[bits[i]],
quant_lut_offset[bits[i]],
quant_lut_offset[bits[i]+1] - 1
)];
if (fabs(coeff - table[best_idx]) > fabs(coeff - table[best_idx + 1]))
best_idx++;
put_bits(&pb, bits[i], best_idx);
}
}
if (!block)
put_bits(&pb, NELLY_HEADER_BITS + NELLY_DETAIL_BITS - put_bits_count(&pb), 0);
}
flush_put_bits(&pb);
memset(put_bits_ptr(&pb), 0, output + output_size - put_bits_ptr(&pb));
}
static int encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
const AVFrame *frame, int *got_packet_ptr)
{
NellyMoserEncodeContext *s = avctx->priv_data;
int ret;
if (s->last_frame)
return 0;
memcpy(s->buf, s->buf + NELLY_SAMPLES, NELLY_BUF_LEN * sizeof(*s->buf));
if (frame) {
memcpy(s->buf + NELLY_BUF_LEN, frame->data[0],
frame->nb_samples * sizeof(*s->buf));
if (frame->nb_samples < NELLY_SAMPLES) {
memset(s->buf + NELLY_BUF_LEN + frame->nb_samples, 0,
(NELLY_SAMPLES - frame->nb_samples) * sizeof(*s->buf));
if (frame->nb_samples >= NELLY_BUF_LEN)
s->last_frame = 1;
}
if ((ret = ff_af_queue_add(&s->afq, frame)) < 0)
return ret;
} else {
memset(s->buf + NELLY_BUF_LEN, 0, NELLY_SAMPLES * sizeof(*s->buf));
s->last_frame = 1;
}
if ((ret = ff_alloc_packet(avpkt, NELLY_BLOCK_LEN))) {
av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");
return ret;
}
encode_block(s, avpkt->data, avpkt->size);
/* Get the next frame pts/duration */
ff_af_queue_remove(&s->afq, avctx->frame_size, &avpkt->pts,
&avpkt->duration);
*got_packet_ptr = 1;
return 0;
}
AVCodec ff_nellymoser_encoder = {
.name = "nellymoser",
.long_name = NULL_IF_CONFIG_SMALL("Nellymoser Asao"),
.type = AVMEDIA_TYPE_AUDIO,
.id = AV_CODEC_ID_NELLYMOSER,
.priv_data_size = sizeof(NellyMoserEncodeContext),
.init = encode_init,
.encode2 = encode_frame,
.close = encode_end,
.capabilities = CODEC_CAP_SMALL_LAST_FRAME | CODEC_CAP_DELAY,
.sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_FLT,
AV_SAMPLE_FMT_NONE },
};