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FFmpeg/libavcodec/flacenc.c
Vittorio Giovara 6064f697a3 lavc: Enable side data only packets by default 
Deprecate the now unused option, but temporarily retain the capability
to disable the now default behaviour.

Mention this change in the AVPacket documentation.

Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
2015-09-12 13:38:31 +02:00

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/*
* FLAC audio encoder
* Copyright (c) 2006 Justin Ruggles <justin.ruggles@gmail.com>
*
* 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
*/
#include "libavutil/crc.h"
#include "libavutil/intmath.h"
#include "libavutil/md5.h"
#include "libavutil/opt.h"
#include "avcodec.h"
#include "bswapdsp.h"
#include "get_bits.h"
#include "golomb.h"
#include "internal.h"
#include "lpc.h"
#include "flac.h"
#include "flacdata.h"
#include "flacdsp.h"
#define FLAC_SUBFRAME_CONSTANT 0
#define FLAC_SUBFRAME_VERBATIM 1
#define FLAC_SUBFRAME_FIXED 8
#define FLAC_SUBFRAME_LPC 32
#define MAX_FIXED_ORDER 4
#define MAX_PARTITION_ORDER 8
#define MAX_PARTITIONS (1 << MAX_PARTITION_ORDER)
#define MAX_LPC_PRECISION 15
#define MAX_LPC_SHIFT 15
enum CodingMode {
CODING_MODE_RICE = 4,
CODING_MODE_RICE2 = 5,
};
typedef struct CompressionOptions {
int compression_level;
int block_time_ms;
enum FFLPCType lpc_type;
int lpc_passes;
int lpc_coeff_precision;
int min_prediction_order;
int max_prediction_order;
int prediction_order_method;
int min_partition_order;
int max_partition_order;
int ch_mode;
} CompressionOptions;
typedef struct RiceContext {
enum CodingMode coding_mode;
int porder;
int params[MAX_PARTITIONS];
uint32_t udata[FLAC_MAX_BLOCKSIZE];
} RiceContext;
typedef struct FlacSubframe {
int type;
int type_code;
int obits;
int wasted;
int order;
int32_t coefs[MAX_LPC_ORDER];
int shift;
RiceContext rc;
int32_t samples[FLAC_MAX_BLOCKSIZE];
int32_t residual[FLAC_MAX_BLOCKSIZE+1];
} FlacSubframe;
typedef struct FlacFrame {
FlacSubframe subframes[FLAC_MAX_CHANNELS];
int blocksize;
int bs_code[2];
uint8_t crc8;
int ch_mode;
int verbatim_only;
} FlacFrame;
typedef struct FlacEncodeContext {
AVClass *class;
PutBitContext pb;
int channels;
int samplerate;
int sr_code[2];
int bps_code;
int max_blocksize;
int min_framesize;
int max_framesize;
int max_encoded_framesize;
uint32_t frame_count;
uint64_t sample_count;
uint8_t md5sum[16];
FlacFrame frame;
CompressionOptions options;
AVCodecContext *avctx;
LPCContext lpc_ctx;
struct AVMD5 *md5ctx;
uint8_t *md5_buffer;
unsigned int md5_buffer_size;
BswapDSPContext bdsp;
FLACDSPContext flac_dsp;
int flushed;
int64_t next_pts;
} FlacEncodeContext;
/**
* Write streaminfo metadata block to byte array.
*/
static void write_streaminfo(FlacEncodeContext *s, uint8_t *header)
{
PutBitContext pb;
memset(header, 0, FLAC_STREAMINFO_SIZE);
init_put_bits(&pb, header, FLAC_STREAMINFO_SIZE);
/* streaminfo metadata block */
put_bits(&pb, 16, s->max_blocksize);
put_bits(&pb, 16, s->max_blocksize);
put_bits(&pb, 24, s->min_framesize);
put_bits(&pb, 24, s->max_framesize);
put_bits(&pb, 20, s->samplerate);
put_bits(&pb, 3, s->channels-1);
put_bits(&pb, 5, s->avctx->bits_per_raw_sample - 1);
/* write 36-bit sample count in 2 put_bits() calls */
put_bits(&pb, 24, (s->sample_count & 0xFFFFFF000LL) >> 12);
put_bits(&pb, 12, s->sample_count & 0x000000FFFLL);
flush_put_bits(&pb);
memcpy(&header[18], s->md5sum, 16);
}
/**
* Set blocksize based on samplerate.
* Choose the closest predefined blocksize >= BLOCK_TIME_MS milliseconds.
*/
static int select_blocksize(int samplerate, int block_time_ms)
{
int i;
int target;
int blocksize;
assert(samplerate > 0);
blocksize = ff_flac_blocksize_table[1];
target = (samplerate * block_time_ms) / 1000;
for (i = 0; i < 16; i++) {
if (target >= ff_flac_blocksize_table[i] &&
ff_flac_blocksize_table[i] > blocksize) {
blocksize = ff_flac_blocksize_table[i];
}
}
return blocksize;
}
static av_cold void dprint_compression_options(FlacEncodeContext *s)
{
AVCodecContext *avctx = s->avctx;
CompressionOptions *opt = &s->options;
av_log(avctx, AV_LOG_DEBUG, " compression: %d\n", opt->compression_level);
switch (opt->lpc_type) {
case FF_LPC_TYPE_NONE:
av_log(avctx, AV_LOG_DEBUG, " lpc type: None\n");
break;
case FF_LPC_TYPE_FIXED:
av_log(avctx, AV_LOG_DEBUG, " lpc type: Fixed pre-defined coefficients\n");
break;
case FF_LPC_TYPE_LEVINSON:
av_log(avctx, AV_LOG_DEBUG, " lpc type: Levinson-Durbin recursion with Welch window\n");
break;
case FF_LPC_TYPE_CHOLESKY:
av_log(avctx, AV_LOG_DEBUG, " lpc type: Cholesky factorization, %d pass%s\n",
opt->lpc_passes, opt->lpc_passes == 1 ? "" : "es");
break;
}
av_log(avctx, AV_LOG_DEBUG, " prediction order: %d, %d\n",
opt->min_prediction_order, opt->max_prediction_order);
switch (opt->prediction_order_method) {
case ORDER_METHOD_EST:
av_log(avctx, AV_LOG_DEBUG, " order method: %s\n", "estimate");
break;
case ORDER_METHOD_2LEVEL:
av_log(avctx, AV_LOG_DEBUG, " order method: %s\n", "2-level");
break;
case ORDER_METHOD_4LEVEL:
av_log(avctx, AV_LOG_DEBUG, " order method: %s\n", "4-level");
break;
case ORDER_METHOD_8LEVEL:
av_log(avctx, AV_LOG_DEBUG, " order method: %s\n", "8-level");
break;
case ORDER_METHOD_SEARCH:
av_log(avctx, AV_LOG_DEBUG, " order method: %s\n", "full search");
break;
case ORDER_METHOD_LOG:
av_log(avctx, AV_LOG_DEBUG, " order method: %s\n", "log search");
break;
}
av_log(avctx, AV_LOG_DEBUG, " partition order: %d, %d\n",
opt->min_partition_order, opt->max_partition_order);
av_log(avctx, AV_LOG_DEBUG, " block size: %d\n", avctx->frame_size);
av_log(avctx, AV_LOG_DEBUG, " lpc precision: %d\n",
opt->lpc_coeff_precision);
}
static av_cold int flac_encode_init(AVCodecContext *avctx)
{
int freq = avctx->sample_rate;
int channels = avctx->channels;
FlacEncodeContext *s = avctx->priv_data;
int i, level, ret;
uint8_t *streaminfo;
s->avctx = avctx;
switch (avctx->sample_fmt) {
case AV_SAMPLE_FMT_S16:
avctx->bits_per_raw_sample = 16;
s->bps_code = 4;
break;
case AV_SAMPLE_FMT_S32:
if (avctx->bits_per_raw_sample != 24)
av_log(avctx, AV_LOG_WARNING, "encoding as 24 bits-per-sample\n");
avctx->bits_per_raw_sample = 24;
s->bps_code = 6;
break;
}
if (channels < 1 || channels > FLAC_MAX_CHANNELS)
return -1;
s->channels = channels;
/* find samplerate in table */
if (freq < 1)
return -1;
for (i = 4; i < 12; i++) {
if (freq == ff_flac_sample_rate_table[i]) {
s->samplerate = ff_flac_sample_rate_table[i];
s->sr_code[0] = i;
s->sr_code[1] = 0;
break;
}
}
/* if not in table, samplerate is non-standard */
if (i == 12) {
if (freq % 1000 == 0 && freq < 255000) {
s->sr_code[0] = 12;
s->sr_code[1] = freq / 1000;
} else if (freq % 10 == 0 && freq < 655350) {
s->sr_code[0] = 14;
s->sr_code[1] = freq / 10;
} else if (freq < 65535) {
s->sr_code[0] = 13;
s->sr_code[1] = freq;
} else {
return -1;
}
s->samplerate = freq;
}
/* set compression option defaults based on avctx->compression_level */
if (avctx->compression_level < 0)
s->options.compression_level = 5;
else
s->options.compression_level = avctx->compression_level;
level = s->options.compression_level;
if (level > 12) {
av_log(avctx, AV_LOG_ERROR, "invalid compression level: %d\n",
s->options.compression_level);
return -1;
}
s->options.block_time_ms = ((int[]){ 27, 27, 27,105,105,105,105,105,105,105,105,105,105})[level];
if (s->options.lpc_type == FF_LPC_TYPE_DEFAULT)
s->options.lpc_type = ((int[]){ FF_LPC_TYPE_FIXED, FF_LPC_TYPE_FIXED, FF_LPC_TYPE_FIXED,
FF_LPC_TYPE_LEVINSON, FF_LPC_TYPE_LEVINSON, FF_LPC_TYPE_LEVINSON,
FF_LPC_TYPE_LEVINSON, FF_LPC_TYPE_LEVINSON, FF_LPC_TYPE_LEVINSON,
FF_LPC_TYPE_LEVINSON, FF_LPC_TYPE_LEVINSON, FF_LPC_TYPE_LEVINSON,
FF_LPC_TYPE_LEVINSON})[level];
s->options.min_prediction_order = ((int[]){ 2, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1})[level];
s->options.max_prediction_order = ((int[]){ 3, 4, 4, 6, 8, 8, 8, 8, 12, 12, 12, 32, 32})[level];
if (s->options.prediction_order_method < 0)
s->options.prediction_order_method = ((int[]){ ORDER_METHOD_EST, ORDER_METHOD_EST, ORDER_METHOD_EST,
ORDER_METHOD_EST, ORDER_METHOD_EST, ORDER_METHOD_EST,
ORDER_METHOD_4LEVEL, ORDER_METHOD_LOG, ORDER_METHOD_4LEVEL,
ORDER_METHOD_LOG, ORDER_METHOD_SEARCH, ORDER_METHOD_LOG,
ORDER_METHOD_SEARCH})[level];
if (s->options.min_partition_order > s->options.max_partition_order) {
av_log(avctx, AV_LOG_ERROR, "invalid partition orders: min=%d max=%d\n",
s->options.min_partition_order, s->options.max_partition_order);
return AVERROR(EINVAL);
}
if (s->options.min_partition_order < 0)
s->options.min_partition_order = ((int[]){ 2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0})[level];
if (s->options.max_partition_order < 0)
s->options.max_partition_order = ((int[]){ 2, 2, 3, 3, 3, 8, 8, 8, 8, 8, 8, 8, 8})[level];
if (s->options.lpc_type == FF_LPC_TYPE_NONE) {
s->options.min_prediction_order = 0;
} else if (avctx->min_prediction_order >= 0) {
if (s->options.lpc_type == FF_LPC_TYPE_FIXED) {
if (avctx->min_prediction_order > MAX_FIXED_ORDER) {
av_log(avctx, AV_LOG_ERROR, "invalid min prediction order: %d\n",
avctx->min_prediction_order);
return -1;
}
} else if (avctx->min_prediction_order < MIN_LPC_ORDER ||
avctx->min_prediction_order > MAX_LPC_ORDER) {
av_log(avctx, AV_LOG_ERROR, "invalid min prediction order: %d\n",
avctx->min_prediction_order);
return -1;
}
s->options.min_prediction_order = avctx->min_prediction_order;
}
if (s->options.lpc_type == FF_LPC_TYPE_NONE) {
s->options.max_prediction_order = 0;
} else if (avctx->max_prediction_order >= 0) {
if (s->options.lpc_type == FF_LPC_TYPE_FIXED) {
if (avctx->max_prediction_order > MAX_FIXED_ORDER) {
av_log(avctx, AV_LOG_ERROR, "invalid max prediction order: %d\n",
avctx->max_prediction_order);
return -1;
}
} else if (avctx->max_prediction_order < MIN_LPC_ORDER ||
avctx->max_prediction_order > MAX_LPC_ORDER) {
av_log(avctx, AV_LOG_ERROR, "invalid max prediction order: %d\n",
avctx->max_prediction_order);
return -1;
}
s->options.max_prediction_order = avctx->max_prediction_order;
}
if (s->options.max_prediction_order < s->options.min_prediction_order) {
av_log(avctx, AV_LOG_ERROR, "invalid prediction orders: min=%d max=%d\n",
s->options.min_prediction_order, s->options.max_prediction_order);
return -1;
}
if (avctx->frame_size > 0) {
if (avctx->frame_size < FLAC_MIN_BLOCKSIZE ||
avctx->frame_size > FLAC_MAX_BLOCKSIZE) {
av_log(avctx, AV_LOG_ERROR, "invalid block size: %d\n",
avctx->frame_size);
return -1;
}
} else {
s->avctx->frame_size = select_blocksize(s->samplerate, s->options.block_time_ms);
}
s->max_blocksize = s->avctx->frame_size;
/* set maximum encoded frame size in verbatim mode */
s->max_framesize = ff_flac_get_max_frame_size(s->avctx->frame_size,
s->channels,
s->avctx->bits_per_raw_sample);
/* initialize MD5 context */
s->md5ctx = av_md5_alloc();
if (!s->md5ctx)
return AVERROR(ENOMEM);
av_md5_init(s->md5ctx);
streaminfo = av_malloc(FLAC_STREAMINFO_SIZE);
if (!streaminfo)
return AVERROR(ENOMEM);
write_streaminfo(s, streaminfo);
avctx->extradata = streaminfo;
avctx->extradata_size = FLAC_STREAMINFO_SIZE;
s->frame_count = 0;
s->min_framesize = s->max_framesize;
ret = ff_lpc_init(&s->lpc_ctx, avctx->frame_size,
s->options.max_prediction_order, FF_LPC_TYPE_LEVINSON);
ff_bswapdsp_init(&s->bdsp);
ff_flacdsp_init(&s->flac_dsp, avctx->sample_fmt,
avctx->bits_per_raw_sample);
dprint_compression_options(s);
return ret;
}
static void init_frame(FlacEncodeContext *s, int nb_samples)
{
int i, ch;
FlacFrame *frame;
frame = &s->frame;
for (i = 0; i < 16; i++) {
if (nb_samples == ff_flac_blocksize_table[i]) {
frame->blocksize = ff_flac_blocksize_table[i];
frame->bs_code[0] = i;
frame->bs_code[1] = 0;
break;
}
}
if (i == 16) {
frame->blocksize = nb_samples;
if (frame->blocksize <= 256) {
frame->bs_code[0] = 6;
frame->bs_code[1] = frame->blocksize-1;
} else {
frame->bs_code[0] = 7;
frame->bs_code[1] = frame->blocksize-1;
}
}
for (ch = 0; ch < s->channels; ch++) {
FlacSubframe *sub = &frame->subframes[ch];
sub->wasted = 0;
sub->obits = s->avctx->bits_per_raw_sample;
if (sub->obits > 16)
sub->rc.coding_mode = CODING_MODE_RICE2;
else
sub->rc.coding_mode = CODING_MODE_RICE;
}
frame->verbatim_only = 0;
}
/**
* Copy channel-interleaved input samples into separate subframes.
*/
static void copy_samples(FlacEncodeContext *s, const void *samples)
{
int i, j, ch;
FlacFrame *frame;
int shift = av_get_bytes_per_sample(s->avctx->sample_fmt) * 8 -
s->avctx->bits_per_raw_sample;
#define COPY_SAMPLES(bits) do { \
const int ## bits ## _t *samples0 = samples; \
frame = &s->frame; \
for (i = 0, j = 0; i < frame->blocksize; i++) \
for (ch = 0; ch < s->channels; ch++, j++) \
frame->subframes[ch].samples[i] = samples0[j] >> shift; \
} while (0)
if (s->avctx->sample_fmt == AV_SAMPLE_FMT_S16)
COPY_SAMPLES(16);
else
COPY_SAMPLES(32);
}
static uint64_t rice_count_exact(int32_t *res, int n, int k)
{
int i;
uint64_t count = 0;
for (i = 0; i < n; i++) {
int32_t v = -2 * res[i] - 1;
v ^= v >> 31;
count += (v >> k) + 1 + k;
}
return count;
}
static uint64_t subframe_count_exact(FlacEncodeContext *s, FlacSubframe *sub,
int pred_order)
{
int p, porder, psize;
int i, part_end;
uint64_t count = 0;
/* subframe header */
count += 8;
/* subframe */
if (sub->type == FLAC_SUBFRAME_CONSTANT) {
count += sub->obits;
} else if (sub->type == FLAC_SUBFRAME_VERBATIM) {
count += s->frame.blocksize * sub->obits;
} else {
/* warm-up samples */
count += pred_order * sub->obits;
/* LPC coefficients */
if (sub->type == FLAC_SUBFRAME_LPC)
count += 4 + 5 + pred_order * s->options.lpc_coeff_precision;
/* rice-encoded block */
count += 2;
/* partition order */
porder = sub->rc.porder;
psize = s->frame.blocksize >> porder;
count += 4;
/* residual */
i = pred_order;
part_end = psize;
for (p = 0; p < 1 << porder; p++) {
int k = sub->rc.params[p];
count += sub->rc.coding_mode;
count += rice_count_exact(&sub->residual[i], part_end - i, k);
i = part_end;
part_end = FFMIN(s->frame.blocksize, part_end + psize);
}
}
return count;
}
#define rice_encode_count(sum, n, k) (((n)*((k)+1))+((sum-(n>>1))>>(k)))
/**
* Solve for d/dk(rice_encode_count) = n-((sum-(n>>1))>>(k+1)) = 0.
*/
static int find_optimal_param(uint64_t sum, int n, int max_param)
{
int k;
uint64_t sum2;
if (sum <= n >> 1)
return 0;
sum2 = sum - (n >> 1);
k = av_log2(av_clipl_int32(sum2 / n));
return FFMIN(k, max_param);
}
static uint64_t calc_optimal_rice_params(RiceContext *rc, int porder,
uint64_t *sums, int n, int pred_order)
{
int i;
int k, cnt, part, max_param;
uint64_t all_bits;
max_param = (1 << rc->coding_mode) - 2;
part = (1 << porder);
all_bits = 4 * part;
cnt = (n >> porder) - pred_order;
for (i = 0; i < part; i++) {
k = find_optimal_param(sums[i], cnt, max_param);
rc->params[i] = k;
all_bits += rice_encode_count(sums[i], cnt, k);
cnt = n >> porder;
}
rc->porder = porder;
return all_bits;
}
static void calc_sums(int pmin, int pmax, uint32_t *data, int n, int pred_order,
uint64_t sums[][MAX_PARTITIONS])
{
int i, j;
int parts;
uint32_t *res, *res_end;
/* sums for highest level */
parts = (1 << pmax);
res = &data[pred_order];
res_end = &data[n >> pmax];
for (i = 0; i < parts; i++) {
uint64_t sum = 0;
while (res < res_end)
sum += *(res++);
sums[pmax][i] = sum;
res_end += n >> pmax;
}
/* sums for lower levels */
for (i = pmax - 1; i >= pmin; i--) {
parts = (1 << i);
for (j = 0; j < parts; j++)
sums[i][j] = sums[i+1][2*j] + sums[i+1][2*j+1];
}
}
static uint64_t calc_rice_params(RiceContext *rc, int pmin, int pmax,
int32_t *data, int n, int pred_order)
{
int i;
uint64_t bits[MAX_PARTITION_ORDER+1];
int opt_porder;
RiceContext tmp_rc;
uint64_t sums[MAX_PARTITION_ORDER + 1][MAX_PARTITIONS] = { { 0 } };
assert(pmin >= 0 && pmin <= MAX_PARTITION_ORDER);
assert(pmax >= 0 && pmax <= MAX_PARTITION_ORDER);
assert(pmin <= pmax);
tmp_rc.coding_mode = rc->coding_mode;
for (i = 0; i < n; i++)
rc->udata[i] = (2 * data[i]) ^ (data[i] >> 31);
calc_sums(pmin, pmax, rc->udata, n, pred_order, sums);
opt_porder = pmin;
bits[pmin] = UINT32_MAX;
for (i = pmin; i <= pmax; i++) {
bits[i] = calc_optimal_rice_params(&tmp_rc, i, sums[i], n, pred_order);
if (bits[i] <= bits[opt_porder]) {
opt_porder = i;
*rc = tmp_rc;
}
}
return bits[opt_porder];
}
static int get_max_p_order(int max_porder, int n, int order)
{
int porder = FFMIN(max_porder, av_log2(n^(n-1)));
if (order > 0)
porder = FFMIN(porder, av_log2(n/order));
return porder;
}
static uint64_t find_subframe_rice_params(FlacEncodeContext *s,
FlacSubframe *sub, int pred_order)
{
int pmin = get_max_p_order(s->options.min_partition_order,
s->frame.blocksize, pred_order);
int pmax = get_max_p_order(s->options.max_partition_order,
s->frame.blocksize, pred_order);
uint64_t bits = 8 + pred_order * sub->obits + 2 + sub->rc.coding_mode;
if (sub->type == FLAC_SUBFRAME_LPC)
bits += 4 + 5 + pred_order * s->options.lpc_coeff_precision;
bits += calc_rice_params(&sub->rc, pmin, pmax, sub->residual,
s->frame.blocksize, pred_order);
return bits;
}
static void encode_residual_fixed(int32_t *res, const int32_t *smp, int n,
int order)
{
int i;
for (i = 0; i < order; i++)
res[i] = smp[i];
if (order == 0) {
for (i = order; i < n; i++)
res[i] = smp[i];
} else if (order == 1) {
for (i = order; i < n; i++)
res[i] = smp[i] - smp[i-1];
} else if (order == 2) {
int a = smp[order-1] - smp[order-2];
for (i = order; i < n; i += 2) {
int b = smp[i ] - smp[i-1];
res[i] = b - a;
a = smp[i+1] - smp[i ];
res[i+1] = a - b;
}
} else if (order == 3) {
int a = smp[order-1] - smp[order-2];
int c = smp[order-1] - 2*smp[order-2] + smp[order-3];
for (i = order; i < n; i += 2) {
int b = smp[i ] - smp[i-1];
int d = b - a;
res[i] = d - c;
a = smp[i+1] - smp[i ];
c = a - b;
res[i+1] = c - d;
}
} else {
int a = smp[order-1] - smp[order-2];
int c = smp[order-1] - 2*smp[order-2] + smp[order-3];
int e = smp[order-1] - 3*smp[order-2] + 3*smp[order-3] - smp[order-4];
for (i = order; i < n; i += 2) {
int b = smp[i ] - smp[i-1];
int d = b - a;
int f = d - c;
res[i ] = f - e;
a = smp[i+1] - smp[i ];
c = a - b;
e = c - d;
res[i+1] = e - f;
}
}
}
static int encode_residual_ch(FlacEncodeContext *s, int ch)
{
int i, n;
int min_order, max_order, opt_order, omethod;
FlacFrame *frame;
FlacSubframe *sub;
int32_t coefs[MAX_LPC_ORDER][MAX_LPC_ORDER];
int shift[MAX_LPC_ORDER];
int32_t *res, *smp;
frame = &s->frame;
sub = &frame->subframes[ch];
res = sub->residual;
smp = sub->samples;
n = frame->blocksize;
/* CONSTANT */
for (i = 1; i < n; i++)
if(smp[i] != smp[0])
break;
if (i == n) {
sub->type = sub->type_code = FLAC_SUBFRAME_CONSTANT;
res[0] = smp[0];
return subframe_count_exact(s, sub, 0);
}
/* VERBATIM */
if (frame->verbatim_only || n < 5) {
sub->type = sub->type_code = FLAC_SUBFRAME_VERBATIM;
memcpy(res, smp, n * sizeof(int32_t));
return subframe_count_exact(s, sub, 0);
}
min_order = s->options.min_prediction_order;
max_order = s->options.max_prediction_order;
omethod = s->options.prediction_order_method;
/* FIXED */
sub->type = FLAC_SUBFRAME_FIXED;
if (s->options.lpc_type == FF_LPC_TYPE_NONE ||
s->options.lpc_type == FF_LPC_TYPE_FIXED || n <= max_order) {
uint64_t bits[MAX_FIXED_ORDER+1];
if (max_order > MAX_FIXED_ORDER)
max_order = MAX_FIXED_ORDER;
opt_order = 0;
bits[0] = UINT32_MAX;
for (i = min_order; i <= max_order; i++) {
encode_residual_fixed(res, smp, n, i);
bits[i] = find_subframe_rice_params(s, sub, i);
if (bits[i] < bits[opt_order])
opt_order = i;
}
sub->order = opt_order;
sub->type_code = sub->type | sub->order;
if (sub->order != max_order) {
encode_residual_fixed(res, smp, n, sub->order);
find_subframe_rice_params(s, sub, sub->order);
}
return subframe_count_exact(s, sub, sub->order);
}
/* LPC */
sub->type = FLAC_SUBFRAME_LPC;
opt_order = ff_lpc_calc_coefs(&s->lpc_ctx, smp, n, min_order, max_order,
s->options.lpc_coeff_precision, coefs, shift, s->options.lpc_type,
s->options.lpc_passes, omethod,
MAX_LPC_SHIFT, 0);
if (omethod == ORDER_METHOD_2LEVEL ||
omethod == ORDER_METHOD_4LEVEL ||
omethod == ORDER_METHOD_8LEVEL) {
int levels = 1 << omethod;
uint64_t bits[1 << ORDER_METHOD_8LEVEL];
int order = -1;
int opt_index = levels-1;
opt_order = max_order-1;
bits[opt_index] = UINT32_MAX;
for (i = levels-1; i >= 0; i--) {
int last_order = order;
order = min_order + (((max_order-min_order+1) * (i+1)) / levels)-1;
order = av_clip(order, min_order - 1, max_order - 1);
if (order == last_order)
continue;
s->flac_dsp.lpc_encode(res, smp, n, order+1, coefs[order],
shift[order]);
bits[i] = find_subframe_rice_params(s, sub, order+1);
if (bits[i] < bits[opt_index]) {
opt_index = i;
opt_order = order;
}
}
opt_order++;
} else if (omethod == ORDER_METHOD_SEARCH) {
// brute-force optimal order search
uint64_t bits[MAX_LPC_ORDER];
opt_order = 0;
bits[0] = UINT32_MAX;
for (i = min_order-1; i < max_order; i++) {
s->flac_dsp.lpc_encode(res, smp, n, i+1, coefs[i], shift[i]);
bits[i] = find_subframe_rice_params(s, sub, i+1);
if (bits[i] < bits[opt_order])
opt_order = i;
}
opt_order++;
} else if (omethod == ORDER_METHOD_LOG) {
uint64_t bits[MAX_LPC_ORDER];
int step;
opt_order = min_order - 1 + (max_order-min_order)/3;
memset(bits, -1, sizeof(bits));
for (step = 16; step; step >>= 1) {
int last = opt_order;
for (i = last-step; i <= last+step; i += step) {
if (i < min_order-1 || i >= max_order || bits[i] < UINT32_MAX)
continue;
s->flac_dsp.lpc_encode(res, smp, n, i+1, coefs[i], shift[i]);
bits[i] = find_subframe_rice_params(s, sub, i+1);
if (bits[i] < bits[opt_order])
opt_order = i;
}
}
opt_order++;
}
sub->order = opt_order;
sub->type_code = sub->type | (sub->order-1);
sub->shift = shift[sub->order-1];
for (i = 0; i < sub->order; i++)
sub->coefs[i] = coefs[sub->order-1][i];
s->flac_dsp.lpc_encode(res, smp, n, sub->order, sub->coefs, sub->shift);
find_subframe_rice_params(s, sub, sub->order);
return subframe_count_exact(s, sub, sub->order);
}
static int count_frame_header(FlacEncodeContext *s)
{
uint8_t av_unused tmp;
int count;
/*
<14> Sync code
<1> Reserved
<1> Blocking strategy
<4> Block size in inter-channel samples
<4> Sample rate
<4> Channel assignment
<3> Sample size in bits
<1> Reserved
*/
count = 32;
/* coded frame number */
PUT_UTF8(s->frame_count, tmp, count += 8;)
/* explicit block size */
if (s->frame.bs_code[0] == 6)
count += 8;
else if (s->frame.bs_code[0] == 7)
count += 16;
/* explicit sample rate */
count += ((s->sr_code[0] == 12) + (s->sr_code[0] > 12)) * 8;
/* frame header CRC-8 */
count += 8;
return count;
}
static int encode_frame(FlacEncodeContext *s)
{
int ch;
uint64_t count;
count = count_frame_header(s);
for (ch = 0; ch < s->channels; ch++)
count += encode_residual_ch(s, ch);
count += (8 - (count & 7)) & 7; // byte alignment
count += 16; // CRC-16
count >>= 3;
if (count > INT_MAX)
return AVERROR_BUG;
return count;
}
static void remove_wasted_bits(FlacEncodeContext *s)
{
int ch, i;
for (ch = 0; ch < s->channels; ch++) {
FlacSubframe *sub = &s->frame.subframes[ch];
int32_t v = 0;
for (i = 0; i < s->frame.blocksize; i++) {
v |= sub->samples[i];
if (v & 1)
break;
}
if (v && !(v & 1)) {
v = av_ctz(v);
for (i = 0; i < s->frame.blocksize; i++)
sub->samples[i] >>= v;
sub->wasted = v;
sub->obits -= v;
/* for 24-bit, check if removing wasted bits makes the range better
suited for using RICE instead of RICE2 for entropy coding */
if (sub->obits <= 17)
sub->rc.coding_mode = CODING_MODE_RICE;
}
}
}
static int estimate_stereo_mode(int32_t *left_ch, int32_t *right_ch, int n,
int max_rice_param)
{
int i, best;
int32_t lt, rt;
uint64_t sum[4];
uint64_t score[4];
int k;
/* calculate sum of 2nd order residual for each channel */
sum[0] = sum[1] = sum[2] = sum[3] = 0;
for (i = 2; i < n; i++) {
lt = left_ch[i] - 2*left_ch[i-1] + left_ch[i-2];
rt = right_ch[i] - 2*right_ch[i-1] + right_ch[i-2];
sum[2] += FFABS((lt + rt) >> 1);
sum[3] += FFABS(lt - rt);
sum[0] += FFABS(lt);
sum[1] += FFABS(rt);
}
/* estimate bit counts */
for (i = 0; i < 4; i++) {
k = find_optimal_param(2 * sum[i], n, max_rice_param);
sum[i] = rice_encode_count( 2 * sum[i], n, k);
}
/* calculate score for each mode */
score[0] = sum[0] + sum[1];
score[1] = sum[0] + sum[3];
score[2] = sum[1] + sum[3];
score[3] = sum[2] + sum[3];
/* return mode with lowest score */
best = 0;
for (i = 1; i < 4; i++)
if (score[i] < score[best])
best = i;
return best;
}
/**
* Perform stereo channel decorrelation.
*/
static void channel_decorrelation(FlacEncodeContext *s)
{
FlacFrame *frame;
int32_t *left, *right;
int i, n;
frame = &s->frame;
n = frame->blocksize;
left = frame->subframes[0].samples;
right = frame->subframes[1].samples;
if (s->channels != 2) {
frame->ch_mode = FLAC_CHMODE_INDEPENDENT;
return;
}
if (s->options.ch_mode < 0) {
int max_rice_param = (1 << frame->subframes[0].rc.coding_mode) - 2;
frame->ch_mode = estimate_stereo_mode(left, right, n, max_rice_param);
} else
frame->ch_mode = s->options.ch_mode;
/* perform decorrelation and adjust bits-per-sample */
if (frame->ch_mode == FLAC_CHMODE_INDEPENDENT)
return;
if (frame->ch_mode == FLAC_CHMODE_MID_SIDE) {
int32_t tmp;
for (i = 0; i < n; i++) {
tmp = left[i];
left[i] = (tmp + right[i]) >> 1;
right[i] = tmp - right[i];
}
frame->subframes[1].obits++;
} else if (frame->ch_mode == FLAC_CHMODE_LEFT_SIDE) {
for (i = 0; i < n; i++)
right[i] = left[i] - right[i];
frame->subframes[1].obits++;
} else {
for (i = 0; i < n; i++)
left[i] -= right[i];
frame->subframes[0].obits++;
}
}
static void write_utf8(PutBitContext *pb, uint32_t val)
{
uint8_t tmp;
PUT_UTF8(val, tmp, put_bits(pb, 8, tmp);)
}
static void write_frame_header(FlacEncodeContext *s)
{
FlacFrame *frame;
int crc;
frame = &s->frame;
put_bits(&s->pb, 16, 0xFFF8);
put_bits(&s->pb, 4, frame->bs_code[0]);
put_bits(&s->pb, 4, s->sr_code[0]);
if (frame->ch_mode == FLAC_CHMODE_INDEPENDENT)
put_bits(&s->pb, 4, s->channels-1);
else
put_bits(&s->pb, 4, frame->ch_mode + FLAC_MAX_CHANNELS - 1);
put_bits(&s->pb, 3, s->bps_code);
put_bits(&s->pb, 1, 0);
write_utf8(&s->pb, s->frame_count);
if (frame->bs_code[0] == 6)
put_bits(&s->pb, 8, frame->bs_code[1]);
else if (frame->bs_code[0] == 7)
put_bits(&s->pb, 16, frame->bs_code[1]);
if (s->sr_code[0] == 12)
put_bits(&s->pb, 8, s->sr_code[1]);
else if (s->sr_code[0] > 12)
put_bits(&s->pb, 16, s->sr_code[1]);
flush_put_bits(&s->pb);
crc = av_crc(av_crc_get_table(AV_CRC_8_ATM), 0, s->pb.buf,
put_bits_count(&s->pb) >> 3);
put_bits(&s->pb, 8, crc);
}
static void write_subframes(FlacEncodeContext *s)
{
int ch;
for (ch = 0; ch < s->channels; ch++) {
FlacSubframe *sub = &s->frame.subframes[ch];
int i, p, porder, psize;
int32_t *part_end;
int32_t *res = sub->residual;
int32_t *frame_end = &sub->residual[s->frame.blocksize];
/* subframe header */
put_bits(&s->pb, 1, 0);
put_bits(&s->pb, 6, sub->type_code);
put_bits(&s->pb, 1, !!sub->wasted);
if (sub->wasted)
put_bits(&s->pb, sub->wasted, 1);
/* subframe */
if (sub->type == FLAC_SUBFRAME_CONSTANT) {
put_sbits(&s->pb, sub->obits, res[0]);
} else if (sub->type == FLAC_SUBFRAME_VERBATIM) {
while (res < frame_end)
put_sbits(&s->pb, sub->obits, *res++);
} else {
/* warm-up samples */
for (i = 0; i < sub->order; i++)
put_sbits(&s->pb, sub->obits, *res++);
/* LPC coefficients */
if (sub->type == FLAC_SUBFRAME_LPC) {
int cbits = s->options.lpc_coeff_precision;
put_bits( &s->pb, 4, cbits-1);
put_sbits(&s->pb, 5, sub->shift);
for (i = 0; i < sub->order; i++)
put_sbits(&s->pb, cbits, sub->coefs[i]);
}
/* rice-encoded block */
put_bits(&s->pb, 2, sub->rc.coding_mode - 4);
/* partition order */
porder = sub->rc.porder;
psize = s->frame.blocksize >> porder;
put_bits(&s->pb, 4, porder);
/* residual */
part_end = &sub->residual[psize];
for (p = 0; p < 1 << porder; p++) {
int k = sub->rc.params[p];
put_bits(&s->pb, sub->rc.coding_mode, k);
while (res < part_end)
set_sr_golomb_flac(&s->pb, *res++, k, INT32_MAX, 0);
part_end = FFMIN(frame_end, part_end + psize);
}
}
}
}
static void write_frame_footer(FlacEncodeContext *s)
{
int crc;
flush_put_bits(&s->pb);
crc = av_bswap16(av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0, s->pb.buf,
put_bits_count(&s->pb)>>3));
put_bits(&s->pb, 16, crc);
flush_put_bits(&s->pb);
}
static int write_frame(FlacEncodeContext *s, AVPacket *avpkt)
{
init_put_bits(&s->pb, avpkt->data, avpkt->size);
write_frame_header(s);
write_subframes(s);
write_frame_footer(s);
return put_bits_count(&s->pb) >> 3;
}
static int update_md5_sum(FlacEncodeContext *s, const void *samples)
{
const uint8_t *buf;
int buf_size = s->frame.blocksize * s->channels *
((s->avctx->bits_per_raw_sample + 7) / 8);
if (s->avctx->bits_per_raw_sample > 16 || HAVE_BIGENDIAN) {
av_fast_malloc(&s->md5_buffer, &s->md5_buffer_size, buf_size);
if (!s->md5_buffer)
return AVERROR(ENOMEM);
}
if (s->avctx->bits_per_raw_sample <= 16) {
buf = (const uint8_t *)samples;
#if HAVE_BIGENDIAN
s->bdsp.bswap16_buf((uint16_t *) s->md5_buffer,
(const uint16_t *) samples, buf_size / 2);
buf = s->md5_buffer;
#endif
} else {
int i;
const int32_t *samples0 = samples;
uint8_t *tmp = s->md5_buffer;
for (i = 0; i < s->frame.blocksize * s->channels; i++) {
int32_t v = samples0[i] >> 8;
*tmp++ = (v ) & 0xFF;
*tmp++ = (v >> 8) & 0xFF;
*tmp++ = (v >> 16) & 0xFF;
}
buf = s->md5_buffer;
}
av_md5_update(s->md5ctx, buf, buf_size);
return 0;
}
static int flac_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
const AVFrame *frame, int *got_packet_ptr)
{
FlacEncodeContext *s;
int frame_bytes, out_bytes, ret;
s = avctx->priv_data;
/* when the last block is reached, update the header in extradata */
if (!frame) {
s->max_framesize = s->max_encoded_framesize;
av_md5_final(s->md5ctx, s->md5sum);
write_streaminfo(s, avctx->extradata);
#if FF_API_SIDEDATA_ONLY_PKT
FF_DISABLE_DEPRECATION_WARNINGS
if (avctx->side_data_only_packets && !s->flushed) {
FF_ENABLE_DEPRECATION_WARNINGS
#else
if (!s->flushed) {
#endif
uint8_t *side_data = av_packet_new_side_data(avpkt, AV_PKT_DATA_NEW_EXTRADATA,
avctx->extradata_size);
if (!side_data)
return AVERROR(ENOMEM);
memcpy(side_data, avctx->extradata, avctx->extradata_size);
avpkt->pts = s->next_pts;
*got_packet_ptr = 1;
s->flushed = 1;
}
return 0;
}
/* change max_framesize for small final frame */
if (frame->nb_samples < s->frame.blocksize) {
s->max_framesize = ff_flac_get_max_frame_size(frame->nb_samples,
s->channels,
avctx->bits_per_raw_sample);
}
init_frame(s, frame->nb_samples);
copy_samples(s, frame->data[0]);
channel_decorrelation(s);
remove_wasted_bits(s);
frame_bytes = encode_frame(s);
/* Fall back on verbatim mode if the compressed frame is larger than it
would be if encoded uncompressed. */
if (frame_bytes < 0 || frame_bytes > s->max_framesize) {
s->frame.verbatim_only = 1;
frame_bytes = encode_frame(s);
if (frame_bytes < 0) {
av_log(avctx, AV_LOG_ERROR, "Bad frame count\n");
return frame_bytes;
}
}
if ((ret = ff_alloc_packet(avpkt, frame_bytes))) {
av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");
return ret;
}
out_bytes = write_frame(s, avpkt);
s->frame_count++;
s->sample_count += frame->nb_samples;
if ((ret = update_md5_sum(s, frame->data[0])) < 0) {
av_log(avctx, AV_LOG_ERROR, "Error updating MD5 checksum\n");
return ret;
}
if (out_bytes > s->max_encoded_framesize)
s->max_encoded_framesize = out_bytes;
if (out_bytes < s->min_framesize)
s->min_framesize = out_bytes;
avpkt->pts = frame->pts;
avpkt->duration = ff_samples_to_time_base(avctx, frame->nb_samples);
avpkt->size = out_bytes;
s->next_pts = avpkt->pts + avpkt->duration;
*got_packet_ptr = 1;
return 0;
}
static av_cold int flac_encode_close(AVCodecContext *avctx)
{
if (avctx->priv_data) {
FlacEncodeContext *s = avctx->priv_data;
av_freep(&s->md5ctx);
av_freep(&s->md5_buffer);
ff_lpc_end(&s->lpc_ctx);
}
av_freep(&avctx->extradata);
avctx->extradata_size = 0;
return 0;
}
#define FLAGS AV_OPT_FLAG_ENCODING_PARAM | AV_OPT_FLAG_AUDIO_PARAM
static const AVOption options[] = {
{ "lpc_coeff_precision", "LPC coefficient precision", offsetof(FlacEncodeContext, options.lpc_coeff_precision), AV_OPT_TYPE_INT, {.i64 = 15 }, 0, MAX_LPC_PRECISION, FLAGS },
{ "lpc_type", "LPC algorithm", offsetof(FlacEncodeContext, options.lpc_type), AV_OPT_TYPE_INT, {.i64 = FF_LPC_TYPE_DEFAULT }, FF_LPC_TYPE_DEFAULT, FF_LPC_TYPE_NB-1, FLAGS, "lpc_type" },
{ "none", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = FF_LPC_TYPE_NONE }, INT_MIN, INT_MAX, FLAGS, "lpc_type" },
{ "fixed", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = FF_LPC_TYPE_FIXED }, INT_MIN, INT_MAX, FLAGS, "lpc_type" },
{ "levinson", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = FF_LPC_TYPE_LEVINSON }, INT_MIN, INT_MAX, FLAGS, "lpc_type" },
{ "cholesky", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = FF_LPC_TYPE_CHOLESKY }, INT_MIN, INT_MAX, FLAGS, "lpc_type" },
{ "lpc_passes", "Number of passes to use for Cholesky factorization during LPC analysis", offsetof(FlacEncodeContext, options.lpc_passes), AV_OPT_TYPE_INT, {.i64 = 1 }, 1, INT_MAX, FLAGS },
{ "min_partition_order", NULL, offsetof(FlacEncodeContext, options.min_partition_order), AV_OPT_TYPE_INT, {.i64 = -1 }, -1, MAX_PARTITION_ORDER, FLAGS },
{ "max_partition_order", NULL, offsetof(FlacEncodeContext, options.max_partition_order), AV_OPT_TYPE_INT, {.i64 = -1 }, -1, MAX_PARTITION_ORDER, FLAGS },
{ "prediction_order_method", "Search method for selecting prediction order", offsetof(FlacEncodeContext, options.prediction_order_method), AV_OPT_TYPE_INT, {.i64 = -1 }, -1, ORDER_METHOD_LOG, FLAGS, "predm" },
{ "estimation", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = ORDER_METHOD_EST }, INT_MIN, INT_MAX, FLAGS, "predm" },
{ "2level", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = ORDER_METHOD_2LEVEL }, INT_MIN, INT_MAX, FLAGS, "predm" },
{ "4level", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = ORDER_METHOD_4LEVEL }, INT_MIN, INT_MAX, FLAGS, "predm" },
{ "8level", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = ORDER_METHOD_8LEVEL }, INT_MIN, INT_MAX, FLAGS, "predm" },
{ "search", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = ORDER_METHOD_SEARCH }, INT_MIN, INT_MAX, FLAGS, "predm" },
{ "log", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = ORDER_METHOD_LOG }, INT_MIN, INT_MAX, FLAGS, "predm" },
{ "ch_mode", "Stereo decorrelation mode", offsetof(FlacEncodeContext, options.ch_mode), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, FLAC_CHMODE_MID_SIDE, FLAGS, "ch_mode" },
{ "auto", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = -1 }, INT_MIN, INT_MAX, FLAGS, "ch_mode" },
{ "indep", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FLAC_CHMODE_INDEPENDENT }, INT_MIN, INT_MAX, FLAGS, "ch_mode" },
{ "left_side", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FLAC_CHMODE_LEFT_SIDE }, INT_MIN, INT_MAX, FLAGS, "ch_mode" },
{ "right_side", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FLAC_CHMODE_RIGHT_SIDE }, INT_MIN, INT_MAX, FLAGS, "ch_mode" },
{ "mid_side", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FLAC_CHMODE_MID_SIDE }, INT_MIN, INT_MAX, FLAGS, "ch_mode" },
{ NULL },
};
static const AVClass flac_encoder_class = {
"FLAC encoder",
av_default_item_name,
options,
LIBAVUTIL_VERSION_INT,
};
AVCodec ff_flac_encoder = {
.name = "flac",
.long_name = NULL_IF_CONFIG_SMALL("FLAC (Free Lossless Audio Codec)"),
.type = AVMEDIA_TYPE_AUDIO,
.id = AV_CODEC_ID_FLAC,
.priv_data_size = sizeof(FlacEncodeContext),
.init = flac_encode_init,
.encode2 = flac_encode_frame,
.close = flac_encode_close,
.capabilities = AV_CODEC_CAP_SMALL_LAST_FRAME | AV_CODEC_CAP_DELAY,
.sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
AV_SAMPLE_FMT_S32,
AV_SAMPLE_FMT_NONE },
.priv_class = &flac_encoder_class,
};
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