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ffmpeg/libavformat/nutenc.c
Anton Khirnov 9200514ad8 lavf: replace AVStream.codec with AVStream.codecpar 
Currently, AVStream contains an embedded AVCodecContext instance, which
is used by demuxers to export stream parameters to the caller and by
muxers to receive stream parameters from the caller. It is also used
internally as the codec context that is passed to parsers.

In addition, it is also widely used by the callers as the decoding (when
demuxer) or encoding (when muxing) context, though this has been
officially discouraged since Libav 11.

There are multiple important problems with this approach:
    - the fields in AVCodecContext are in general one of
        * stream parameters
        * codec options
        * codec state
      However, it's not clear which ones are which. It is consequently
      unclear which fields are a demuxer allowed to set or a muxer allowed to
      read. This leads to erratic behaviour depending on whether decoding or
      encoding is being performed or not (and whether it uses the AVStream
      embedded codec context).
    - various synchronization issues arising from the fact that the same
      context is used by several different APIs (muxers/demuxers,
      parsers, bitstream filters and encoders/decoders) simultaneously, with
      there being no clear rules for who can modify what and the different
      processes being typically delayed with respect to each other.
    - avformat_find_stream_info() making it necessary to support opening
      and closing a single codec context multiple times, thus
      complicating the semantics of freeing various allocated objects in the
      codec context.

Those problems are resolved by replacing the AVStream embedded codec
context with a newly added AVCodecParameters instance, which stores only
the stream parameters exported by the demuxers or read by the muxers.
2016-02-23 17:01:58 +01:00

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/*
* nut muxer
* Copyright (c) 2004-2007 Michael Niedermayer
*
* 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 <stdint.h>
#include "libavutil/intreadwrite.h"
#include "libavutil/mathematics.h"
#include "libavutil/tree.h"
#include "libavutil/dict.h"
#include "libavutil/time.h"
#include "libavutil/opt.h"
#include "libavcodec/mpegaudiodata.h"
#include "nut.h"
#include "internal.h"
#include "avio_internal.h"
#include "riff.h"
static int find_expected_header(AVCodecParameters *p, int size, int key_frame,
uint8_t out[64])
{
int sample_rate = p->sample_rate;
if (size > 4096)
return 0;
AV_WB24(out, 1);
if (p->codec_id == AV_CODEC_ID_MPEG4) {
if (key_frame) {
return 3;
} else {
out[3] = 0xB6;
return 4;
}
} else if (p->codec_id == AV_CODEC_ID_MPEG1VIDEO ||
p->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
return 3;
} else if (p->codec_id == AV_CODEC_ID_H264) {
return 3;
} else if (p->codec_id == AV_CODEC_ID_MP3 ||
p->codec_id == AV_CODEC_ID_MP2) {
int lsf, mpeg25, sample_rate_index, bitrate_index, frame_size;
int layer = p->codec_id == AV_CODEC_ID_MP3 ? 3 : 2;
unsigned int header = 0xFFF00000;
lsf = sample_rate < (24000 + 32000) / 2;
mpeg25 = sample_rate < (12000 + 16000) / 2;
sample_rate <<= lsf + mpeg25;
if (sample_rate < (32000 + 44100) / 2)
sample_rate_index = 2;
else if (sample_rate < (44100 + 48000) / 2)
sample_rate_index = 0;
else
sample_rate_index = 1;
sample_rate = avpriv_mpa_freq_tab[sample_rate_index] >> (lsf + mpeg25);
for (bitrate_index = 2; bitrate_index < 30; bitrate_index++) {
frame_size =
avpriv_mpa_bitrate_tab[lsf][layer - 1][bitrate_index >> 1];
frame_size = (frame_size * 144000) / (sample_rate << lsf) +
(bitrate_index & 1);
if (frame_size == size)
break;
}
header |= (!lsf) << 19;
header |= (4 - layer) << 17;
header |= 1 << 16; //no crc
AV_WB32(out, header);
if (size <= 0)
return 2; //we guess there is no crc, if there is one the user clearly does not care about overhead
if (bitrate_index == 30)
return -1; //something is wrong ...
header |= (bitrate_index >> 1) << 12;
header |= sample_rate_index << 10;
header |= (bitrate_index & 1) << 9;
return 2; //FIXME actually put the needed ones in build_elision_headers()
//return 3; //we guess that the private bit is not set
//FIXME the above assumptions should be checked, if these turn out false too often something should be done
}
return 0;
}
static int find_header_idx(AVFormatContext *s, AVCodecParameters *p, int size,
int frame_type)
{
NUTContext *nut = s->priv_data;
uint8_t out[64];
int i;
int len = find_expected_header(p, size, frame_type, out);
for (i = 1; i < nut->header_count; i++) {
if (len == nut->header_len[i] && !memcmp(out, nut->header[i], len)) {
return i;
}
}
return 0;
}
static void build_elision_headers(AVFormatContext *s)
{
NUTContext *nut = s->priv_data;
int i;
//FIXME this is lame
//FIXME write a 2pass mode to find the maximal headers
static const uint8_t headers[][5] = {
{ 3, 0x00, 0x00, 0x01 },
{ 4, 0x00, 0x00, 0x01, 0xB6},
{ 2, 0xFF, 0xFA }, //mp3+crc
{ 2, 0xFF, 0xFB }, //mp3
{ 2, 0xFF, 0xFC }, //mp2+crc
{ 2, 0xFF, 0xFD }, //mp2
};
nut->header_count = 7;
for (i = 1; i < nut->header_count; i++) {
nut->header_len[i] = headers[i - 1][0];
nut->header[i] = &headers[i - 1][1];
}
}
static void build_frame_code(AVFormatContext *s)
{
NUTContext *nut = s->priv_data;
int key_frame, index, pred, stream_id;
int start = 1;
int end = 254;
int keyframe_0_esc = s->nb_streams > 2;
int pred_table[10];
FrameCode *ft;
ft = &nut->frame_code[start];
ft->flags = FLAG_CODED;
ft->size_mul = 1;
ft->pts_delta = 1;
start++;
if (keyframe_0_esc) {
/* keyframe = 0 escape */
FrameCode *ft = &nut->frame_code[start];
ft->flags = FLAG_STREAM_ID | FLAG_SIZE_MSB | FLAG_CODED_PTS;
ft->size_mul = 1;
start++;
}
for (stream_id = 0; stream_id < s->nb_streams; stream_id++) {
int start2 = start + (end - start) * stream_id / s->nb_streams;
int end2 = start + (end - start) * (stream_id + 1) / s->nb_streams;
AVCodecParameters *par = s->streams[stream_id]->codecpar;
const AVCodecDescriptor *desc = avcodec_descriptor_get(par->codec_id);
int is_audio = par->codec_type == AVMEDIA_TYPE_AUDIO;
int intra_only = /*codec->intra_only || */ is_audio;
int pred_count;
for (key_frame = 0; key_frame < 2; key_frame++) {
if (!intra_only || !keyframe_0_esc || key_frame != 0) {
FrameCode *ft = &nut->frame_code[start2];
ft->flags = FLAG_KEY * key_frame;
ft->flags |= FLAG_SIZE_MSB | FLAG_CODED_PTS;
ft->stream_id = stream_id;
ft->size_mul = 1;
if (is_audio)
ft->header_idx = find_header_idx(s, par, -1, key_frame);
start2++;
}
}
key_frame = intra_only;
if (is_audio) {
int frame_bytes;
int pts;
if (par->block_align > 0) {
frame_bytes = par->block_align;
} else {
int frame_size = av_get_audio_frame_duration2(par, 0);
frame_bytes = frame_size * (int64_t)par->bit_rate / (8 * par->sample_rate);
}
for (pts = 0; pts < 2; pts++)
for (pred = 0; pred < 2; pred++) {
FrameCode *ft = &nut->frame_code[start2];
ft->flags = FLAG_KEY * key_frame;
ft->stream_id = stream_id;
ft->size_mul = frame_bytes + 2;
ft->size_lsb = frame_bytes + pred;
ft->pts_delta = pts;
ft->header_idx = find_header_idx(s, par, frame_bytes + pred, key_frame);
start2++;
}
} else {
FrameCode *ft = &nut->frame_code[start2];
ft->flags = FLAG_KEY | FLAG_SIZE_MSB;
ft->stream_id = stream_id;
ft->size_mul = 1;
ft->pts_delta = 1;
start2++;
}
if (desc && desc->props & AV_CODEC_PROP_REORDER) {
pred_count = 5;
pred_table[0] = -2;
pred_table[1] = -1;
pred_table[2] = 1;
pred_table[3] = 3;
pred_table[4] = 4;
} else if (par->codec_id == AV_CODEC_ID_VORBIS) {
pred_count = 3;
pred_table[0] = 2;
pred_table[1] = 9;
pred_table[2] = 16;
} else {
pred_count = 1;
pred_table[0] = 1;
}
for (pred = 0; pred < pred_count; pred++) {
int start3 = start2 + (end2 - start2) * pred / pred_count;
int end3 = start2 + (end2 - start2) * (pred + 1) / pred_count;
for (index = start3; index < end3; index++) {
FrameCode *ft = &nut->frame_code[index];
ft->flags = FLAG_KEY * key_frame;
ft->flags |= FLAG_SIZE_MSB;
ft->stream_id = stream_id;
//FIXME use single byte size and pred from last
ft->size_mul = end3 - start3;
ft->size_lsb = index - start3;
ft->pts_delta = pred_table[pred];
if (is_audio)
ft->header_idx = find_header_idx(s, par, -1, key_frame);
}
}
}
memmove(&nut->frame_code['N' + 1], &nut->frame_code['N'],
sizeof(FrameCode) * (255 - 'N'));
nut->frame_code[0].flags =
nut->frame_code[255].flags =
nut->frame_code['N'].flags = FLAG_INVALID;
}
static void put_tt(NUTContext *nut, AVRational *time_base, AVIOContext *bc,
uint64_t val)
{
val *= nut->time_base_count;
val += time_base - nut->time_base;
ff_put_v(bc, val);
}
/**
* Store a string as vb.
*/
static void put_str(AVIOContext *bc, const char *string)
{
int len = strlen(string);
ff_put_v(bc, len);
avio_write(bc, string, len);
}
static void put_s(AVIOContext *bc, int64_t val)
{
ff_put_v(bc, 2 * FFABS(val) - (val > 0));
}
#ifdef TRACE
static inline void ff_put_v_trace(AVIOContext *bc, uint64_t v, const char *file,
const char *func, int line)
{
av_log(NULL, AV_LOG_DEBUG, "ff_put_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
ff_put_v(bc, v);
}
static inline void put_s_trace(AVIOContext *bc, int64_t v, const char *file,
const char *func, int line)
{
av_log(NULL, AV_LOG_DEBUG, "put_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
put_s(bc, v);
}
#define ff_put_v(bc, v) ff_put_v_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#define put_s(bc, v) put_s_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#endif
//FIXME remove calculate_checksum
static void put_packet(NUTContext *nut, AVIOContext *bc, AVIOContext *dyn_bc,
int calculate_checksum, uint64_t startcode)
{
uint8_t *dyn_buf = NULL;
int dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);
int forw_ptr = dyn_size + 4 * calculate_checksum;
if (forw_ptr > 4096)
ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);
avio_wb64(bc, startcode);
ff_put_v(bc, forw_ptr);
if (forw_ptr > 4096)
avio_wl32(bc, ffio_get_checksum(bc));
if (calculate_checksum)
ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);
avio_write(bc, dyn_buf, dyn_size);
if (calculate_checksum)
avio_wl32(bc, ffio_get_checksum(bc));
av_free(dyn_buf);
}
static void write_mainheader(NUTContext *nut, AVIOContext *bc)
{
int i, j, tmp_pts, tmp_flags, tmp_stream, tmp_mul, tmp_size, tmp_fields,
tmp_head_idx;
int64_t tmp_match;
ff_put_v(bc, nut->version);
ff_put_v(bc, nut->avf->nb_streams);
ff_put_v(bc, nut->max_distance);
ff_put_v(bc, nut->time_base_count);
for (i = 0; i < nut->time_base_count; i++) {
ff_put_v(bc, nut->time_base[i].num);
ff_put_v(bc, nut->time_base[i].den);
}
tmp_pts = 0;
tmp_mul = 1;
tmp_stream = 0;
tmp_match = 1 - (1LL << 62);
tmp_head_idx = 0;
for (i = 0; i < 256; ) {
tmp_fields = 0;
tmp_size = 0;
// tmp_res=0;
if (tmp_pts != nut->frame_code[i].pts_delta)
tmp_fields = 1;
if (tmp_mul != nut->frame_code[i].size_mul)
tmp_fields = 2;
if (tmp_stream != nut->frame_code[i].stream_id)
tmp_fields = 3;
if (tmp_size != nut->frame_code[i].size_lsb)
tmp_fields = 4;
// if(tmp_res != nut->frame_code[i].res ) tmp_fields=5;
if (tmp_head_idx != nut->frame_code[i].header_idx)
tmp_fields = 8;
tmp_pts = nut->frame_code[i].pts_delta;
tmp_flags = nut->frame_code[i].flags;
tmp_stream = nut->frame_code[i].stream_id;
tmp_mul = nut->frame_code[i].size_mul;
tmp_size = nut->frame_code[i].size_lsb;
// tmp_res = nut->frame_code[i].res;
tmp_head_idx = nut->frame_code[i].header_idx;
for (j = 0; i < 256; j++, i++) {
if (i == 'N') {
j--;
continue;
}
if (nut->frame_code[i].pts_delta != tmp_pts ||
nut->frame_code[i].flags != tmp_flags ||
nut->frame_code[i].stream_id != tmp_stream ||
nut->frame_code[i].size_mul != tmp_mul ||
nut->frame_code[i].size_lsb != tmp_size + j ||
// nut->frame_code[i].res != tmp_res ||
nut->frame_code[i].header_idx != tmp_head_idx)
break;
}
if (j != tmp_mul - tmp_size)
tmp_fields = 6;
ff_put_v(bc, tmp_flags);
ff_put_v(bc, tmp_fields);
if (tmp_fields > 0)
put_s(bc, tmp_pts);
if (tmp_fields > 1)
ff_put_v(bc, tmp_mul);
if (tmp_fields > 2)
ff_put_v(bc, tmp_stream);
if (tmp_fields > 3)
ff_put_v(bc, tmp_size);
if (tmp_fields > 4)
ff_put_v(bc, 0 /*tmp_res*/);
if (tmp_fields > 5)
ff_put_v(bc, j);
if (tmp_fields > 6)
ff_put_v(bc, tmp_match);
if (tmp_fields > 7)
ff_put_v(bc, tmp_head_idx);
}
ff_put_v(bc, nut->header_count - 1);
for (i = 1; i < nut->header_count; i++) {
ff_put_v(bc, nut->header_len[i]);
avio_write(bc, nut->header[i], nut->header_len[i]);
}
// flags had been effectively introduced in version 4
if (nut->version > NUT_STABLE_VERSION)
ff_put_v(bc, nut->flags);
}
static int write_streamheader(AVFormatContext *avctx, AVIOContext *bc,
AVStream *st, int i)
{
NUTContext *nut = avctx->priv_data;
AVCodecParameters *par = st->codecpar;
const AVCodecDescriptor *desc = avcodec_descriptor_get(par->codec_id);
unsigned codec_tag = av_codec_get_tag(ff_nut_codec_tags, par->codec_id);
ff_put_v(bc, i);
switch (par->codec_type) {
case AVMEDIA_TYPE_VIDEO:
ff_put_v(bc, 0);
break;
case AVMEDIA_TYPE_AUDIO:
ff_put_v(bc, 1);
break;
case AVMEDIA_TYPE_SUBTITLE:
ff_put_v(bc, 2);
break;
default:
ff_put_v(bc, 3);
break;
}
ff_put_v(bc, 4);
if (av_codec_get_id(ff_nut_codec_tags, par->codec_tag) == par->codec_id ||
!codec_tag || par->codec_id == AV_CODEC_ID_RAWVIDEO)
codec_tag = par->codec_tag;
if (codec_tag) {
avio_wl32(bc, codec_tag);
} else {
av_log(avctx, AV_LOG_ERROR, "No codec tag defined for stream %d\n", i);
return AVERROR(EINVAL);
}
ff_put_v(bc, nut->stream[i].time_base - nut->time_base);
ff_put_v(bc, nut->stream[i].msb_pts_shift);
ff_put_v(bc, nut->stream[i].max_pts_distance);
ff_put_v(bc, (desc && desc->props & AV_CODEC_PROP_REORDER) ? 16 : 0);
avio_w8(bc, 0); /* flags: 0x1 - fixed_fps, 0x2 - index_present */
ff_put_v(bc, par->extradata_size);
avio_write(bc, par->extradata, par->extradata_size);
switch (par->codec_type) {
case AVMEDIA_TYPE_AUDIO:
ff_put_v(bc, par->sample_rate);
ff_put_v(bc, 1);
ff_put_v(bc, par->channels);
break;
case AVMEDIA_TYPE_VIDEO:
ff_put_v(bc, par->width);
ff_put_v(bc, par->height);
if (st->sample_aspect_ratio.num <= 0 ||
st->sample_aspect_ratio.den <= 0) {
ff_put_v(bc, 0);
ff_put_v(bc, 0);
} else {
ff_put_v(bc, st->sample_aspect_ratio.num);
ff_put_v(bc, st->sample_aspect_ratio.den);
}
ff_put_v(bc, 0); /* csp type -- unknown */
break;
default:
break;
}
return 0;
}
static int add_info(AVIOContext *bc, const char *type, const char *value)
{
put_str(bc, type);
put_s(bc, -1);
put_str(bc, value);
return 1;
}
static int write_globalinfo(NUTContext *nut, AVIOContext *bc)
{
AVFormatContext *s = nut->avf;
AVDictionaryEntry *t = NULL;
AVIOContext *dyn_bc;
uint8_t *dyn_buf = NULL;
int count = 0, dyn_size;
int ret = avio_open_dyn_buf(&dyn_bc);
if (ret < 0)
return ret;
while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX)))
count += add_info(dyn_bc, t->key, t->value);
ff_put_v(bc, 0); //stream_if_plus1
ff_put_v(bc, 0); //chapter_id
ff_put_v(bc, 0); //timestamp_start
ff_put_v(bc, 0); //length
ff_put_v(bc, count);
dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);
avio_write(bc, dyn_buf, dyn_size);
av_free(dyn_buf);
return 0;
}
static int write_streaminfo(NUTContext *nut, AVIOContext *bc, int stream_id){
AVFormatContext *s= nut->avf;
AVStream* st = s->streams[stream_id];
AVIOContext *dyn_bc;
uint8_t *dyn_buf=NULL;
int count=0, dyn_size, i;
int ret = avio_open_dyn_buf(&dyn_bc);
if(ret < 0)
return ret;
for (i=0; ff_nut_dispositions[i].flag; ++i) {
if (st->disposition & ff_nut_dispositions[i].flag)
count += add_info(dyn_bc, "Disposition", ff_nut_dispositions[i].str);
}
dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);
if (count) {
ff_put_v(bc, stream_id + 1); //stream_id_plus1
ff_put_v(bc, 0); //chapter_id
ff_put_v(bc, 0); //timestamp_start
ff_put_v(bc, 0); //length
ff_put_v(bc, count);
avio_write(bc, dyn_buf, dyn_size);
}
av_free(dyn_buf);
return count;
}
static int write_chapter(NUTContext *nut, AVIOContext *bc, int id)
{
AVIOContext *dyn_bc;
uint8_t *dyn_buf = NULL;
AVDictionaryEntry *t = NULL;
AVChapter *ch = nut->avf->chapters[id];
int ret, dyn_size, count = 0;
ret = avio_open_dyn_buf(&dyn_bc);
if (ret < 0)
return ret;
ff_put_v(bc, 0); // stream_id_plus1
put_s(bc, id + 1); // chapter_id
put_tt(nut, nut->chapter[id].time_base, bc, ch->start); // chapter_start
ff_put_v(bc, ch->end - ch->start); // chapter_len
while ((t = av_dict_get(ch->metadata, "", t, AV_DICT_IGNORE_SUFFIX)))
count += add_info(dyn_bc, t->key, t->value);
ff_put_v(bc, count);
dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);
avio_write(bc, dyn_buf, dyn_size);
av_freep(&dyn_buf);
return 0;
}
static int write_headers(AVFormatContext *avctx, AVIOContext *bc)
{
NUTContext *nut = avctx->priv_data;
AVIOContext *dyn_bc;
int i, ret;
ff_metadata_conv_ctx(avctx, ff_nut_metadata_conv, NULL);
ret = avio_open_dyn_buf(&dyn_bc);
if (ret < 0)
return ret;
write_mainheader(nut, dyn_bc);
put_packet(nut, bc, dyn_bc, 1, MAIN_STARTCODE);
for (i = 0; i < nut->avf->nb_streams; i++) {
ret = avio_open_dyn_buf(&dyn_bc);
if (ret < 0)
return ret;
ret = write_streamheader(avctx, dyn_bc, nut->avf->streams[i], i);
if (ret < 0)
return ret;
put_packet(nut, bc, dyn_bc, 1, STREAM_STARTCODE);
}
ret = avio_open_dyn_buf(&dyn_bc);
if (ret < 0)
return ret;
write_globalinfo(nut, dyn_bc);
put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);
for (i = 0; i < nut->avf->nb_streams; i++) {
ret = avio_open_dyn_buf(&dyn_bc);
if (ret < 0)
return ret;
ret = write_streaminfo(nut, dyn_bc, i);
if (ret < 0)
return ret;
if (ret > 0)
put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);
else
ffio_free_dyn_buf(&dyn_bc);
}
for (i = 0; i < nut->avf->nb_chapters; i++) {
ret = avio_open_dyn_buf(&dyn_bc);
if (ret < 0)
return ret;
ret = write_chapter(nut, dyn_bc, i);
if (ret < 0) {
ffio_free_dyn_buf(&dyn_bc);
return ret;
}
put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);
}
nut->last_syncpoint_pos = INT_MIN;
nut->header_count++;
return 0;
}
static int nut_write_header(AVFormatContext *s)
{
NUTContext *nut = s->priv_data;
AVIOContext *bc = s->pb;
int i, j, ret;
nut->avf = s;
nut->version = NUT_STABLE_VERSION + !!nut->flags;
if (nut->flags && s->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL) {
av_log(s, AV_LOG_ERROR,
"The additional syncpoint modes require version %d, "
"that is currently not finalized, "
"please set -f_strict experimental in order to enable it.\n",
nut->version);
return AVERROR_EXPERIMENTAL;
}
nut->stream = av_mallocz(sizeof(StreamContext) * s->nb_streams);
if (s->nb_chapters)
nut->chapter = av_mallocz(sizeof(ChapterContext) * s->nb_chapters);
nut->time_base = av_mallocz(sizeof(AVRational) * (s->nb_streams +
s->nb_chapters));
if (!nut->stream || (s->nb_chapters && !nut->chapter) || !nut->time_base) {
av_freep(&nut->stream);
av_freep(&nut->chapter);
av_freep(&nut->time_base);
return AVERROR(ENOMEM);
}
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
int ssize;
AVRational time_base;
ff_parse_specific_params(st, &time_base.den, &ssize,
&time_base.num);
avpriv_set_pts_info(st, 64, time_base.num, time_base.den);
for (j = 0; j < nut->time_base_count; j++)
if (!memcmp(&time_base, &nut->time_base[j], sizeof(AVRational))) {
break;
}
nut->time_base[j] = time_base;
nut->stream[i].time_base = &nut->time_base[j];
if (j == nut->time_base_count)
nut->time_base_count++;
if (INT64_C(1000) * time_base.num >= time_base.den)
nut->stream[i].msb_pts_shift = 7;
else
nut->stream[i].msb_pts_shift = 14;
nut->stream[i].max_pts_distance =
FFMAX(time_base.den, time_base.num) / time_base.num;
}
for (i = 0; i < s->nb_chapters; i++) {
AVChapter *ch = s->chapters[i];
for (j = 0; j < nut->time_base_count; j++)
if (!memcmp(&ch->time_base, &nut->time_base[j], sizeof(AVRational)))
break;
nut->time_base[j] = ch->time_base;
nut->chapter[i].time_base = &nut->time_base[j];
if (j == nut->time_base_count)
nut->time_base_count++;
}
nut->max_distance = MAX_DISTANCE;
build_elision_headers(s);
build_frame_code(s);
assert(nut->frame_code['N'].flags == FLAG_INVALID);
avio_write(bc, ID_STRING, strlen(ID_STRING));
avio_w8(bc, 0);
if ((ret = write_headers(s, bc)) < 0)
return ret;
avio_flush(bc);
//FIXME index
return 0;
}
static int get_needed_flags(NUTContext *nut, StreamContext *nus, FrameCode *fc,
AVPacket *pkt)
{
int flags = 0;
if (pkt->flags & AV_PKT_FLAG_KEY)
flags |= FLAG_KEY;
if (pkt->stream_index != fc->stream_id)
flags |= FLAG_STREAM_ID;
if (pkt->size / fc->size_mul)
flags |= FLAG_SIZE_MSB;
if (pkt->pts - nus->last_pts != fc->pts_delta)
flags |= FLAG_CODED_PTS;
if (pkt->size > 2 * nut->max_distance)
flags |= FLAG_CHECKSUM;
if (FFABS(pkt->pts - nus->last_pts) > nus->max_pts_distance)
flags |= FLAG_CHECKSUM;
if (pkt->size < nut->header_len[fc->header_idx] ||
(pkt->size > 4096 && fc->header_idx) ||
memcmp(pkt->data, nut->header[fc->header_idx],
nut->header_len[fc->header_idx]))
flags |= FLAG_HEADER_IDX;
return flags | (fc->flags & FLAG_CODED);
}
static int find_best_header_idx(NUTContext *nut, AVPacket *pkt)
{
int i;
int best_i = 0;
int best_len = 0;
if (pkt->size > 4096)
return 0;
for (i = 1; i < nut->header_count; i++)
if (pkt->size >= nut->header_len[i]
&& nut->header_len[i] > best_len
&& !memcmp(pkt->data, nut->header[i], nut->header_len[i])) {
best_i = i;
best_len = nut->header_len[i];
}
return best_i;
}
static int nut_write_packet(AVFormatContext *s, AVPacket *pkt)
{
NUTContext *nut = s->priv_data;
StreamContext *nus = &nut->stream[pkt->stream_index];
AVIOContext *bc = s->pb, *dyn_bc;
FrameCode *fc;
int64_t coded_pts;
int best_length, frame_code, flags, needed_flags, i, header_idx,
best_header_idx;
int key_frame = !!(pkt->flags & AV_PKT_FLAG_KEY);
int store_sp = 0;
int ret;
if (pkt->pts < 0) {
av_log(s, AV_LOG_ERROR,
"Negative pts not supported stream %d, pts %"PRId64"\n",
pkt->stream_index, pkt->pts);
return AVERROR_INVALIDDATA;
}
if (1LL << (20 + 3 * nut->header_count) <= avio_tell(bc))
write_headers(s, bc);
if (key_frame && !(nus->last_flags & FLAG_KEY))
store_sp = 1;
if (pkt->size + 30 /*FIXME check*/ + avio_tell(bc) >=
nut->last_syncpoint_pos + nut->max_distance)
store_sp = 1;
//FIXME: Ensure store_sp is 1 in the first place.
if (store_sp &&
(!(nut->flags & NUT_PIPE) || nut->last_syncpoint_pos == INT_MIN)) {
Syncpoint *sp, dummy = { .pos = INT64_MAX };
ff_nut_reset_ts(nut, *nus->time_base, pkt->dts);
for (i = 0; i < s->nb_streams; i++) {
AVStream *st = s->streams[i];
int64_t dts_tb = av_rescale_rnd(pkt->dts,
nus->time_base->num * (int64_t)nut->stream[i].time_base->den,
nus->time_base->den * (int64_t)nut->stream[i].time_base->num,
AV_ROUND_DOWN);
int index = av_index_search_timestamp(st, dts_tb,
AVSEEK_FLAG_BACKWARD);
if (index >= 0)
dummy.pos = FFMIN(dummy.pos, st->index_entries[index].pos);
}
if (dummy.pos == INT64_MAX)
dummy.pos = 0;
sp = av_tree_find(nut->syncpoints, &dummy, (void *)ff_nut_sp_pos_cmp,
NULL);
nut->last_syncpoint_pos = avio_tell(bc);
ret = avio_open_dyn_buf(&dyn_bc);
if (ret < 0)
return ret;
put_tt(nut, nus->time_base, dyn_bc, pkt->dts);
ff_put_v(dyn_bc, sp ? (nut->last_syncpoint_pos - sp->pos) >> 4 : 0);
if (nut->flags & NUT_BROADCAST) {
put_tt(nut, nus->time_base, dyn_bc,
av_rescale_q(av_gettime(), AV_TIME_BASE_Q, *nus->time_base));
}
put_packet(nut, bc, dyn_bc, 1, SYNCPOINT_STARTCODE);
if ((ret = ff_nut_add_sp(nut, nut->last_syncpoint_pos, 0 /*unused*/, pkt->dts)) < 0)
return ret;
}
assert(nus->last_pts != AV_NOPTS_VALUE);
coded_pts = pkt->pts & ((1 << nus->msb_pts_shift) - 1);
if (ff_lsb2full(nus, coded_pts) != pkt->pts)
coded_pts = pkt->pts + (1 << nus->msb_pts_shift);
best_header_idx = find_best_header_idx(nut, pkt);
best_length = INT_MAX;
frame_code = -1;
for (i = 0; i < 256; i++) {
int length = 0;
FrameCode *fc = &nut->frame_code[i];
int flags = fc->flags;
if (flags & FLAG_INVALID)
continue;
needed_flags = get_needed_flags(nut, nus, fc, pkt);
if (flags & FLAG_CODED) {
length++;
flags = needed_flags;
}
if ((flags & needed_flags) != needed_flags)
continue;
if ((flags ^ needed_flags) & FLAG_KEY)
continue;
if (flags & FLAG_STREAM_ID)
length += ff_get_v_length(pkt->stream_index);
if (pkt->size % fc->size_mul != fc->size_lsb)
continue;
if (flags & FLAG_SIZE_MSB)
length += ff_get_v_length(pkt->size / fc->size_mul);
if (flags & FLAG_CHECKSUM)
length += 4;
if (flags & FLAG_CODED_PTS)
length += ff_get_v_length(coded_pts);
if ((flags & FLAG_CODED)
&& nut->header_len[best_header_idx] >
nut->header_len[fc->header_idx] + 1) {
flags |= FLAG_HEADER_IDX;
}
if (flags & FLAG_HEADER_IDX) {
length += 1 - nut->header_len[best_header_idx];
} else {
length -= nut->header_len[fc->header_idx];
}
length *= 4;
length += !(flags & FLAG_CODED_PTS);
length += !(flags & FLAG_CHECKSUM);
if (length < best_length) {
best_length = length;
frame_code = i;
}
}
if (frame_code < 0)
return AVERROR_BUG;
fc = &nut->frame_code[frame_code];
flags = fc->flags;
needed_flags = get_needed_flags(nut, nus, fc, pkt);
header_idx = fc->header_idx;
ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);
avio_w8(bc, frame_code);
if (flags & FLAG_CODED) {
ff_put_v(bc, (flags ^ needed_flags) & ~(FLAG_CODED));
flags = needed_flags;
}
if (flags & FLAG_STREAM_ID)
ff_put_v(bc, pkt->stream_index);
if (flags & FLAG_CODED_PTS)
ff_put_v(bc, coded_pts);
if (flags & FLAG_SIZE_MSB)
ff_put_v(bc, pkt->size / fc->size_mul);
if (flags & FLAG_HEADER_IDX)
ff_put_v(bc, header_idx = best_header_idx);
if (flags & FLAG_CHECKSUM)
avio_wl32(bc, ffio_get_checksum(bc));
else
ffio_get_checksum(bc);
avio_write(bc, pkt->data + nut->header_len[header_idx],
pkt->size - nut->header_len[header_idx]);
nus->last_flags = flags;
nus->last_pts = pkt->pts;
//FIXME just store one per syncpoint
if (flags & FLAG_KEY && !(nut->flags & NUT_PIPE))
av_add_index_entry(
s->streams[pkt->stream_index],
nut->last_syncpoint_pos,
pkt->pts,
0,
0,
AVINDEX_KEYFRAME);
return 0;
}
static int nut_write_trailer(AVFormatContext *s)
{
NUTContext *nut = s->priv_data;
AVIOContext *bc = s->pb;
while (nut->header_count < 3)
write_headers(s, bc);
ff_nut_free_sp(nut);
av_freep(&nut->stream);
av_freep(&nut->chapter);
av_freep(&nut->time_base);
return 0;
}
#define OFFSET(x) offsetof(NUTContext, x)
#define E AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
{ "syncpoints", "NUT syncpoint behaviour", OFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, INT_MIN, INT_MAX, E, "syncpoints" },
{ "default", "", 0, AV_OPT_TYPE_CONST, {.i64 = 0}, INT_MIN, INT_MAX, E, "syncpoints" },
{ "none", "Disable syncpoints, low overhead and unseekable", 0, AV_OPT_TYPE_CONST, {.i64 = NUT_PIPE}, INT_MIN, INT_MAX, E, "syncpoints" },
{ "timestamped", "Extend syncpoints with a wallclock timestamp", 0, AV_OPT_TYPE_CONST, {.i64 = NUT_BROADCAST}, INT_MIN, INT_MAX, E, "syncpoints" },
{ NULL },
};
static const AVClass class = {
.class_name = "nutenc",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
AVOutputFormat ff_nut_muxer = {
.name = "nut",
.long_name = NULL_IF_CONFIG_SMALL("NUT"),
.mime_type = "video/x-nut",
.extensions = "nut",
.priv_data_size = sizeof(NUTContext),
.audio_codec = CONFIG_LIBVORBIS ? AV_CODEC_ID_VORBIS :
CONFIG_LIBMP3LAME ? AV_CODEC_ID_MP3 : AV_CODEC_ID_MP2,
.video_codec = AV_CODEC_ID_MPEG4,
.write_header = nut_write_header,
.write_packet = nut_write_packet,
.write_trailer = nut_write_trailer,
.flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS,
.codec_tag = ff_nut_codec_tags,
.priv_class = &class,
};
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