mirror of https://github.com/FFmpeg/FFmpeg.git
This is mostly to serve as a reference example on how to segment the output from the mp4 muxer, capable of writing the segment list in four different ways: - SegmentTemplate with SegmentTimeline - SegmentTemplate with implicit segments - SegmentList with individual files - SegmentList with one single file per track, and byte ranges The muxer is able to serve live content (with optional windowing) or create a static segmented MPD. In advanced cases, users will probably want to do the segmenting in their own application code. Signed-off-by: Martin Storsjö <martin@martin.st>pull/96/head
parent
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6 changed files with 779 additions and 3 deletions
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/*
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* MPEG-DASH ISO BMFF segmenter |
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* Copyright (c) 2014 Martin Storsjo |
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* |
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* This file is part of Libav. |
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* |
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* Libav is free software; you can redistribute it and/or |
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* modify it under the terms of the GNU Lesser General Public |
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* License as published by the Free Software Foundation; either |
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* version 2.1 of the License, or (at your option) any later version. |
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* |
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* Libav is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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* Lesser General Public License for more details. |
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* |
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* You should have received a copy of the GNU Lesser General Public |
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* License along with Libav; if not, write to the Free Software |
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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*/ |
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#include "config.h" |
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#if HAVE_UNISTD_H |
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#include <unistd.h> |
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#endif |
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#include "libavutil/avstring.h" |
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#include "libavutil/intreadwrite.h" |
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#include "libavutil/mathematics.h" |
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#include "libavutil/opt.h" |
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#include "libavutil/time_internal.h" |
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#include "avc.h" |
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#include "avformat.h" |
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#include "avio_internal.h" |
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#include "internal.h" |
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#include "isom.h" |
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#include "os_support.h" |
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#include "url.h" |
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typedef struct Segment { |
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char file[1024]; |
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int64_t start_pos; |
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int range_length, index_length; |
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int64_t time; |
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int duration; |
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int n; |
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} Segment; |
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typedef struct OutputStream { |
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AVFormatContext *ctx; |
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int ctx_inited; |
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uint8_t iobuf[32768]; |
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URLContext *out; |
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int packets_written; |
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char initfile[1024]; |
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int64_t init_start_pos; |
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int init_range_length; |
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int nb_segments, segments_size, segment_index; |
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Segment **segments; |
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int64_t first_dts, start_dts, end_dts; |
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char codec_str[100]; |
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} OutputStream; |
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typedef struct DASHContext { |
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const AVClass *class; /* Class for private options. */ |
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int window_size; |
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int extra_window_size; |
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int min_seg_duration; |
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int remove_at_exit; |
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int use_template; |
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int use_timeline; |
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int single_file; |
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OutputStream *streams; |
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int has_video, has_audio; |
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int nb_segments; |
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int last_duration; |
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int total_duration; |
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char availability_start_time[100]; |
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char dirname[1024]; |
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} DASHContext; |
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static int dash_write(void *opaque, uint8_t *buf, int buf_size) |
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{ |
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OutputStream *os = opaque; |
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if (os->out) |
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ffurl_write(os->out, buf, buf_size); |
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return buf_size; |
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} |
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// RFC 6381
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static void set_codec_str(AVFormatContext *s, AVCodecContext *codec, |
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char *str, int size) |
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{ |
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const AVCodecTag *tags[2] = { NULL, NULL }; |
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uint32_t tag; |
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if (codec->codec_type == AVMEDIA_TYPE_VIDEO) |
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tags[0] = ff_codec_movvideo_tags; |
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else if (codec->codec_type == AVMEDIA_TYPE_AUDIO) |
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tags[0] = ff_codec_movaudio_tags; |
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else |
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return; |
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tag = av_codec_get_tag(tags, codec->codec_id); |
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if (!tag) |
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return; |
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if (size < 5) |
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return; |
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AV_WL32(str, tag); |
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str[4] = '\0'; |
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if (!strcmp(str, "mp4a") || !strcmp(str, "mp4v")) { |
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uint32_t oti; |
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tags[0] = ff_mp4_obj_type; |
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oti = av_codec_get_tag(tags, codec->codec_id); |
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if (oti) |
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av_strlcatf(str, size, ".%02x", oti); |
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else |
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return; |
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if (tag == MKTAG('m', 'p', '4', 'a')) { |
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if (codec->extradata_size >= 2) { |
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int aot = codec->extradata[0] >> 3; |
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if (aot == 31) |
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aot = ((AV_RB16(codec->extradata) >> 5) & 0x3f) + 32; |
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av_strlcatf(str, size, ".%d", aot); |
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} |
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} else if (tag == MKTAG('m', 'p', '4', 'v')) { |
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// Unimplemented, should output ProfileLevelIndication as a decimal number
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av_log(s, AV_LOG_WARNING, "Incomplete RFC 6381 codec string for mp4v\n"); |
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} |
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} else if (!strcmp(str, "avc1")) { |
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uint8_t *tmpbuf = NULL; |
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uint8_t *extradata = codec->extradata; |
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int extradata_size = codec->extradata_size; |
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if (!extradata_size) |
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return; |
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if (extradata[0] != 1) { |
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AVIOContext *pb; |
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if (avio_open_dyn_buf(&pb) < 0) |
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return; |
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if (ff_isom_write_avcc(pb, extradata, extradata_size) < 0) { |
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avio_close_dyn_buf(pb, &tmpbuf); |
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av_free(tmpbuf); |
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return; |
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} |
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extradata_size = avio_close_dyn_buf(pb, &extradata); |
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tmpbuf = extradata; |
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} |
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if (extradata_size >= 4) |
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av_strlcatf(str, size, ".%02x%02x%02x", |
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extradata[1], extradata[2], extradata[3]); |
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av_free(tmpbuf); |
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} |
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} |
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static void dash_free(AVFormatContext *s) |
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{ |
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DASHContext *c = s->priv_data; |
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int i, j; |
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if (!c->streams) |
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return; |
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for (i = 0; i < s->nb_streams; i++) { |
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OutputStream *os = &c->streams[i]; |
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if (os->ctx && os->ctx_inited) |
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av_write_trailer(os->ctx); |
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if (os->ctx && os->ctx->pb) |
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av_free(os->ctx->pb); |
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ffurl_close(os->out); |
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os->out = NULL; |
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if (os->ctx) |
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avformat_free_context(os->ctx); |
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for (j = 0; j < os->nb_segments; j++) |
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av_free(os->segments[j]); |
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av_free(os->segments); |
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} |
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av_freep(&c->streams); |
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} |
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static void output_segment_list(OutputStream *os, AVIOContext *out, DASHContext *c) |
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{ |
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int i, start_index = 0, start_number = 1; |
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if (c->window_size) { |
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start_index = FFMAX(os->nb_segments - c->window_size, 0); |
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start_number = FFMAX(os->segment_index - c->window_size, 1); |
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} |
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if (c->use_template) { |
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int timescale = c->use_timeline ? os->ctx->streams[0]->time_base.den : AV_TIME_BASE; |
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avio_printf(out, "\t\t\t\t<SegmentTemplate timescale=\"%d\" ", timescale); |
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if (!c->use_timeline) |
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avio_printf(out, "duration=\"%d\" ", c->last_duration); |
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avio_printf(out, "initialization=\"init-stream$RepresentationID$.m4s\" media=\"chunk-stream$RepresentationID$-$Number%%05d$.m4s\" startNumber=\"%d\">\n", c->use_timeline ? start_number : 1); |
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if (c->use_timeline) { |
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avio_printf(out, "\t\t\t\t\t<SegmentTimeline>\n"); |
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for (i = start_index; i < os->nb_segments; ) { |
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Segment *seg = os->segments[i]; |
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int repeat = 0; |
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avio_printf(out, "\t\t\t\t\t\t<S "); |
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if (i == start_index) |
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avio_printf(out, "t=\"%"PRId64"\" ", seg->time); |
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avio_printf(out, "d=\"%d\" ", seg->duration); |
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while (i + repeat + 1 < os->nb_segments && os->segments[i + repeat + 1]->duration == seg->duration) |
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repeat++; |
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if (repeat > 0) |
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avio_printf(out, "r=\"%d\" ", repeat); |
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avio_printf(out, "/>\n"); |
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i += 1 + repeat; |
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} |
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avio_printf(out, "\t\t\t\t\t</SegmentTimeline>\n"); |
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} |
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avio_printf(out, "\t\t\t\t</SegmentTemplate>\n"); |
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} else if (c->single_file) { |
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avio_printf(out, "\t\t\t\t<BaseURL>%s</BaseURL>\n", os->initfile); |
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avio_printf(out, "\t\t\t\t<SegmentList timescale=\"%d\" duration=\"%d\" startNumber=\"%d\">\n", AV_TIME_BASE, c->last_duration, start_number); |
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avio_printf(out, "\t\t\t\t\t<Initialization range=\"%"PRId64"-%"PRId64"\" />\n", os->init_start_pos, os->init_start_pos + os->init_range_length - 1); |
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for (i = start_index; i < os->nb_segments; i++) { |
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Segment *seg = os->segments[i]; |
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avio_printf(out, "\t\t\t\t\t<SegmentURL mediaRange=\"%"PRId64"-%"PRId64"\" ", seg->start_pos, seg->start_pos + seg->range_length - 1); |
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if (seg->index_length) |
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avio_printf(out, "indexRange=\"%"PRId64"-%"PRId64"\" ", seg->start_pos, seg->start_pos + seg->index_length - 1); |
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avio_printf(out, "/>\n"); |
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} |
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avio_printf(out, "\t\t\t\t</SegmentList>\n"); |
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} else { |
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avio_printf(out, "\t\t\t\t<SegmentList timescale=\"%d\" duration=\"%d\" startNumber=\"%d\">\n", AV_TIME_BASE, c->last_duration, start_number); |
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avio_printf(out, "\t\t\t\t\t<Initialization sourceURL=\"%s\" />\n", os->initfile); |
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for (i = start_index; i < os->nb_segments; i++) { |
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Segment *seg = os->segments[i]; |
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avio_printf(out, "\t\t\t\t\t<SegmentURL media=\"%s\" />\n", seg->file); |
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} |
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avio_printf(out, "\t\t\t\t</SegmentList>\n"); |
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} |
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} |
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static char *xmlescape(const char *str) { |
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int outlen = strlen(str)*3/2 + 6; |
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char *out = av_realloc(NULL, outlen + 1); |
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int pos = 0; |
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if (!out) |
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return NULL; |
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for (; *str; str++) { |
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if (pos + 6 > outlen) { |
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char *tmp; |
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outlen = 2 * outlen + 6; |
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tmp = av_realloc(out, outlen + 1); |
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if (!tmp) { |
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av_free(out); |
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return NULL; |
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} |
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out = tmp; |
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} |
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if (*str == '&') { |
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memcpy(&out[pos], "&", 5); |
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pos += 5; |
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} else if (*str == '<') { |
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memcpy(&out[pos], "<", 4); |
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pos += 4; |
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} else if (*str == '>') { |
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memcpy(&out[pos], ">", 4); |
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pos += 4; |
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} else if (*str == '\'') { |
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memcpy(&out[pos], "'", 6); |
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pos += 6; |
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} else if (*str == '\"') { |
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memcpy(&out[pos], """, 6); |
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pos += 6; |
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} else { |
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out[pos++] = *str; |
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} |
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} |
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out[pos] = '\0'; |
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return out; |
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} |
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static void write_time(AVIOContext *out, int64_t time) |
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{ |
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int seconds = time / AV_TIME_BASE; |
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int fractions = time % AV_TIME_BASE; |
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int minutes = seconds / 60; |
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int hours = minutes / 60; |
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seconds %= 60; |
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minutes %= 60; |
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avio_printf(out, "PT"); |
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if (hours) |
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avio_printf(out, "%dH", hours); |
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if (hours || minutes) |
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avio_printf(out, "%dM", minutes); |
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avio_printf(out, "%d.%dS", seconds, fractions / (AV_TIME_BASE / 10)); |
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} |
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static int write_manifest(AVFormatContext *s, int final) |
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{ |
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DASHContext *c = s->priv_data; |
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AVIOContext *out; |
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char temp_filename[1024]; |
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int ret, i; |
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AVDictionaryEntry *title = av_dict_get(s->metadata, "title", NULL, 0); |
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snprintf(temp_filename, sizeof(temp_filename), "%s.tmp", s->filename); |
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ret = avio_open2(&out, temp_filename, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL); |
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if (ret < 0) { |
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av_log(s, AV_LOG_ERROR, "Unable to open %s for writing\n", temp_filename); |
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return ret; |
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} |
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avio_printf(out, "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"); |
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avio_printf(out, "<MPD xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\n" |
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"\txmlns=\"urn:mpeg:dash:schema:mpd:2011\"\n" |
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"\txmlns:xlink=\"http://www.w3.org/1999/xlink\"\n" |
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"\txsi:schemaLocation=\"urn:mpeg:DASH:schema:MPD:2011 http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-DASH_schema_files/DASH-MPD.xsd\"\n" |
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"\tprofiles=\"urn:mpeg:dash:profile:isoff-live:2011\"\n" |
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"\ttype=\"%s\"\n", final ? "static" : "dynamic"); |
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if (final) { |
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avio_printf(out, "\tmediaPresentationDuration=\""); |
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write_time(out, c->total_duration); |
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avio_printf(out, "\"\n"); |
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} else { |
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int update_period = c->last_duration / AV_TIME_BASE; |
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if (c->use_template && !c->use_timeline) |
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update_period = 500; |
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avio_printf(out, "\tminimumUpdatePeriod=\"PT%dS\"\n", update_period); |
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avio_printf(out, "\tsuggestedPresentationDelay=\"PT%dS\"\n", c->last_duration / AV_TIME_BASE); |
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if (!c->availability_start_time[0] && s->nb_streams > 0 && c->streams[0].nb_segments > 0) { |
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time_t t = time(NULL); |
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struct tm *ptm, tmbuf; |
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ptm = gmtime_r(&t, &tmbuf); |
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if (ptm) { |
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if (!strftime(c->availability_start_time, sizeof(c->availability_start_time), |
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"%Y-%m-%dT%H:%M:%S", ptm)) |
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c->availability_start_time[0] = '\0'; |
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} |
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} |
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if (c->availability_start_time[0]) |
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avio_printf(out, "\tavailabilityStartTime=\"%s\"\n", c->availability_start_time); |
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if (c->window_size && c->use_template) { |
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avio_printf(out, "\ttimeShiftBufferDepth=\""); |
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write_time(out, c->last_duration * c->window_size); |
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avio_printf(out, "\"\n"); |
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} |
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} |
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avio_printf(out, "\tminBufferTime=\""); |
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write_time(out, c->last_duration); |
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avio_printf(out, "\">\n"); |
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avio_printf(out, "\t<ProgramInformation>\n"); |
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if (title) { |
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char *escaped = xmlescape(title->value); |
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avio_printf(out, "\t\t<Title>%s</Title>\n", escaped); |
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av_free(escaped); |
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} |
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avio_printf(out, "\t</ProgramInformation>\n"); |
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if (c->window_size && s->nb_streams > 0 && c->streams[0].nb_segments > 0 && !c->use_template) { |
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OutputStream *os = &c->streams[0]; |
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int start_index = FFMAX(os->nb_segments - c->window_size, 0); |
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int64_t start_time = av_rescale_q(os->segments[start_index]->time, s->streams[0]->time_base, AV_TIME_BASE_Q); |
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avio_printf(out, "\t<Period start=\""); |
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write_time(out, start_time); |
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avio_printf(out, "\">\n"); |
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} else { |
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avio_printf(out, "\t<Period start=\"PT0.0S\">\n"); |
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} |
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if (c->has_video) { |
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avio_printf(out, "\t\t<AdaptationSet id=\"video\" segmentAlignment=\"true\" bitstreamSwitching=\"true\">\n"); |
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for (i = 0; i < s->nb_streams; i++) { |
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AVStream *st = s->streams[i]; |
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OutputStream *os = &c->streams[i]; |
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if (s->streams[i]->codec->codec_type != AVMEDIA_TYPE_VIDEO) |
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continue; |
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avio_printf(out, "\t\t\t<Representation id=\"%d\" mimeType=\"video/mp4\" codecs=\"%s\" bandwidth=\"%d\" width=\"%d\" height=\"%d\">\n", i, os->codec_str, st->codec->bit_rate, st->codec->width, st->codec->height); |
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output_segment_list(&c->streams[i], out, c); |
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avio_printf(out, "\t\t\t</Representation>\n"); |
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} |
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avio_printf(out, "\t\t</AdaptationSet>\n"); |
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} |
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if (c->has_audio) { |
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avio_printf(out, "\t\t<AdaptationSet id=\"audio\" segmentAlignment=\"true\" bitstreamSwitching=\"true\">\n"); |
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for (i = 0; i < s->nb_streams; i++) { |
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AVStream *st = s->streams[i]; |
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OutputStream *os = &c->streams[i]; |
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if (s->streams[i]->codec->codec_type != AVMEDIA_TYPE_AUDIO) |
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continue; |
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avio_printf(out, "\t\t\t<Representation id=\"%d\" mimeType=\"audio/mp4\" codecs=\"%s\" bandwidth=\"%d\" audioSamplingRate=\"%d\">\n", i, os->codec_str, st->codec->bit_rate, st->codec->sample_rate); |
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avio_printf(out, "\t\t\t\t<AudioChannelConfiguration schemeIdUri=\"urn:mpeg:dash:23003:3:audio_channel_configuration:2011\" value=\"%d\" />\n", st->codec->channels); |
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output_segment_list(&c->streams[i], out, c); |
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avio_printf(out, "\t\t\t</Representation>\n"); |
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} |
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avio_printf(out, "\t\t</AdaptationSet>\n"); |
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} |
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avio_printf(out, "\t</Period>\n"); |
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avio_printf(out, "</MPD>\n"); |
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avio_flush(out); |
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avio_close(out); |
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return ff_rename(temp_filename, s->filename); |
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} |
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|
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static int dash_write_header(AVFormatContext *s) |
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{ |
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DASHContext *c = s->priv_data; |
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int ret = 0, i; |
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AVOutputFormat *oformat; |
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char *ptr; |
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char basename[1024]; |
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|
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if (c->single_file) |
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c->use_template = 0; |
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|
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av_strlcpy(c->dirname, s->filename, sizeof(c->dirname)); |
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ptr = strrchr(c->dirname, '/'); |
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if (ptr) { |
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av_strlcpy(basename, &ptr[1], sizeof(basename)); |
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ptr[1] = '\0'; |
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} else { |
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c->dirname[0] = '\0'; |
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av_strlcpy(basename, s->filename, sizeof(basename)); |
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} |
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|
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ptr = strrchr(basename, '.'); |
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if (ptr) |
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*ptr = '\0'; |
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|
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oformat = av_guess_format("mp4", NULL, NULL); |
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if (!oformat) { |
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ret = AVERROR_MUXER_NOT_FOUND; |
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goto fail; |
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} |
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|
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c->streams = av_mallocz(sizeof(*c->streams) * s->nb_streams); |
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if (!c->streams) { |
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ret = AVERROR(ENOMEM); |
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goto fail; |
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} |
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|
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for (i = 0; i < s->nb_streams; i++) { |
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OutputStream *os = &c->streams[i]; |
||||
AVFormatContext *ctx; |
||||
AVStream *st; |
||||
AVDictionary *opts = NULL; |
||||
char filename[1024]; |
||||
|
||||
if (!s->streams[i]->codec->bit_rate) { |
||||
av_log(s, AV_LOG_ERROR, "No bit rate set for stream %d\n", i); |
||||
ret = AVERROR(EINVAL); |
||||
goto fail; |
||||
} |
||||
|
||||
ctx = avformat_alloc_context(); |
||||
if (!ctx) { |
||||
ret = AVERROR(ENOMEM); |
||||
goto fail; |
||||
} |
||||
os->ctx = ctx; |
||||
ctx->oformat = oformat; |
||||
ctx->interrupt_callback = s->interrupt_callback; |
||||
|
||||
if (!(st = avformat_new_stream(ctx, NULL))) { |
||||
ret = AVERROR(ENOMEM); |
||||
goto fail; |
||||
} |
||||
avcodec_copy_context(st->codec, s->streams[i]->codec); |
||||
st->sample_aspect_ratio = s->streams[i]->sample_aspect_ratio; |
||||
st->time_base = s->streams[i]->time_base; |
||||
ctx->avoid_negative_ts = s->avoid_negative_ts; |
||||
|
||||
ctx->pb = avio_alloc_context(os->iobuf, sizeof(os->iobuf), AVIO_FLAG_WRITE, os, NULL, dash_write, NULL); |
||||
if (!ctx->pb) { |
||||
ret = AVERROR(ENOMEM); |
||||
goto fail; |
||||
} |
||||
|
||||
if (c->single_file) |
||||
snprintf(os->initfile, sizeof(os->initfile), "%s-stream%d.m4s", basename, i); |
||||
else |
||||
snprintf(os->initfile, sizeof(os->initfile), "init-stream%d.m4s", i); |
||||
snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->initfile); |
||||
ret = ffurl_open(&os->out, filename, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL); |
||||
if (ret < 0) |
||||
goto fail; |
||||
os->init_start_pos = 0; |
||||
|
||||
av_dict_set(&opts, "movflags", "frag_custom+dash", 0); |
||||
if ((ret = avformat_write_header(ctx, &opts)) < 0) { |
||||
goto fail; |
||||
} |
||||
os->ctx_inited = 1; |
||||
avio_flush(ctx->pb); |
||||
av_dict_free(&opts); |
||||
|
||||
if (c->single_file) { |
||||
os->init_range_length = avio_tell(ctx->pb); |
||||
} else { |
||||
ffurl_close(os->out); |
||||
os->out = NULL; |
||||
} |
||||
|
||||
s->streams[i]->time_base = st->time_base; |
||||
// If the muxer wants to shift timestamps, request to have them shifted
|
||||
// already before being handed to this muxer, so we don't have mismatches
|
||||
// between the MPD and the actual segments.
|
||||
s->avoid_negative_ts = ctx->avoid_negative_ts; |
||||
if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) |
||||
c->has_video = 1; |
||||
else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) |
||||
c->has_audio = 1; |
||||
|
||||
set_codec_str(s, os->ctx->streams[0]->codec, os->codec_str, sizeof(os->codec_str)); |
||||
os->first_dts = AV_NOPTS_VALUE; |
||||
os->segment_index = 1; |
||||
} |
||||
|
||||
if (!c->has_video && c->min_seg_duration <= 0) { |
||||
av_log(s, AV_LOG_WARNING, "no video stream and no min seg duration set\n"); |
||||
ret = AVERROR(EINVAL); |
||||
} |
||||
ret = write_manifest(s, 0); |
||||
|
||||
fail: |
||||
if (ret) |
||||
dash_free(s); |
||||
return ret; |
||||
} |
||||
|
||||
static int add_segment(OutputStream *os, const char *file, |
||||
int64_t time, int duration, |
||||
int64_t start_pos, int64_t range_length, |
||||
int64_t index_length) |
||||
{ |
||||
int err; |
||||
Segment *seg; |
||||
if (os->nb_segments >= os->segments_size) { |
||||
os->segments_size = (os->segments_size + 1) * 2; |
||||
if ((err = av_reallocp(&os->segments, sizeof(*os->segments) * |
||||
os->segments_size)) < 0) { |
||||
os->segments_size = 0; |
||||
os->nb_segments = 0; |
||||
return err; |
||||
} |
||||
} |
||||
seg = av_mallocz(sizeof(*seg)); |
||||
if (!seg) |
||||
return AVERROR(ENOMEM); |
||||
av_strlcpy(seg->file, file, sizeof(seg->file)); |
||||
seg->time = time; |
||||
seg->duration = duration; |
||||
seg->start_pos = start_pos; |
||||
seg->range_length = range_length; |
||||
seg->index_length = index_length; |
||||
os->segments[os->nb_segments++] = seg; |
||||
os->segment_index++; |
||||
return 0; |
||||
} |
||||
|
||||
static void write_styp(AVIOContext *pb) |
||||
{ |
||||
avio_wb32(pb, 24); |
||||
ffio_wfourcc(pb, "styp"); |
||||
ffio_wfourcc(pb, "msdh"); |
||||
avio_wb32(pb, 0); /* minor */ |
||||
ffio_wfourcc(pb, "msdh"); |
||||
ffio_wfourcc(pb, "msix"); |
||||
} |
||||
|
||||
static void find_index_range(AVFormatContext *s, const char *dirname, |
||||
const char *filename, int64_t pos, |
||||
int *index_length) |
||||
{ |
||||
char full_path[1024]; |
||||
uint8_t buf[8]; |
||||
URLContext *fd; |
||||
int ret; |
||||
|
||||
snprintf(full_path, sizeof(full_path), "%s%s", dirname, filename); |
||||
ret = ffurl_open(&fd, full_path, AVIO_FLAG_READ, &s->interrupt_callback, NULL); |
||||
if (ret < 0) |
||||
return; |
||||
if (ffurl_seek(fd, pos, SEEK_SET) != pos) { |
||||
ffurl_close(fd); |
||||
return; |
||||
} |
||||
ret = ffurl_read(fd, buf, 8); |
||||
ffurl_close(fd); |
||||
if (ret < 8) |
||||
return; |
||||
if (AV_RL32(&buf[4]) != MKTAG('s', 'i', 'd', 'x')) |
||||
return; |
||||
*index_length = AV_RB32(&buf[0]); |
||||
} |
||||
|
||||
static int dash_flush(AVFormatContext *s, int final) |
||||
{ |
||||
DASHContext *c = s->priv_data; |
||||
int i, ret = 0; |
||||
|
||||
for (i = 0; i < s->nb_streams; i++) { |
||||
OutputStream *os = &c->streams[i]; |
||||
char filename[1024] = "", full_path[1024], temp_path[1024]; |
||||
int64_t start_pos = avio_tell(os->ctx->pb); |
||||
int range_length, index_length = 0; |
||||
|
||||
if (!os->packets_written) |
||||
continue; |
||||
|
||||
if (!c->single_file) { |
||||
snprintf(filename, sizeof(filename), "chunk-stream%d-%05d.m4s", i, os->segment_index); |
||||
snprintf(full_path, sizeof(full_path), "%s%s", c->dirname, filename); |
||||
snprintf(temp_path, sizeof(temp_path), "%s.tmp", full_path); |
||||
ret = ffurl_open(&os->out, temp_path, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL); |
||||
if (ret < 0) |
||||
break; |
||||
write_styp(os->ctx->pb); |
||||
} |
||||
av_write_frame(os->ctx, NULL); |
||||
avio_flush(os->ctx->pb); |
||||
os->packets_written = 0; |
||||
|
||||
range_length = avio_tell(os->ctx->pb) - start_pos; |
||||
if (c->single_file) { |
||||
find_index_range(s, c->dirname, os->initfile, start_pos, &index_length); |
||||
} else { |
||||
ffurl_close(os->out); |
||||
os->out = NULL; |
||||
ret = ff_rename(temp_path, full_path); |
||||
if (ret < 0) |
||||
break; |
||||
} |
||||
add_segment(os, filename, os->start_dts, os->end_dts - os->start_dts, start_pos, range_length, index_length); |
||||
} |
||||
|
||||
if (c->window_size || (final && c->remove_at_exit)) { |
||||
for (i = 0; i < s->nb_streams; i++) { |
||||
OutputStream *os = &c->streams[i]; |
||||
int j; |
||||
int remove = os->nb_segments - c->window_size - c->extra_window_size; |
||||
if (final && c->remove_at_exit) |
||||
remove = os->nb_segments; |
||||
if (remove > 0) { |
||||
for (j = 0; j < remove; j++) { |
||||
char filename[1024]; |
||||
snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->segments[j]->file); |
||||
unlink(filename); |
||||
av_free(os->segments[j]); |
||||
} |
||||
os->nb_segments -= remove; |
||||
memmove(os->segments, os->segments + remove, os->nb_segments * sizeof(*os->segments)); |
||||
} |
||||
} |
||||
} |
||||
|
||||
if (ret >= 0) |
||||
ret = write_manifest(s, final); |
||||
return ret; |
||||
} |
||||
|
||||
static int dash_write_packet(AVFormatContext *s, AVPacket *pkt) |
||||
{ |
||||
DASHContext *c = s->priv_data; |
||||
AVStream *st = s->streams[pkt->stream_index]; |
||||
OutputStream *os = &c->streams[pkt->stream_index]; |
||||
int64_t seg_end_duration = (c->nb_segments + 1) * (int64_t) c->min_seg_duration; |
||||
int ret; |
||||
|
||||
// If forcing the stream to start at 0, the mp4 muxer will set the start
|
||||
// timestamps to 0. Do the same here, to avoid mismatches in duration/timestamps.
|
||||
if (os->first_dts == AV_NOPTS_VALUE && |
||||
s->avoid_negative_ts == AVFMT_AVOID_NEG_TS_MAKE_ZERO) { |
||||
pkt->pts -= pkt->dts; |
||||
pkt->dts = 0; |
||||
} |
||||
|
||||
if (os->first_dts == AV_NOPTS_VALUE) |
||||
os->first_dts = pkt->dts; |
||||
|
||||
if ((!c->has_video || st->codec->codec_type == AVMEDIA_TYPE_VIDEO) && |
||||
pkt->flags & AV_PKT_FLAG_KEY && os->packets_written && |
||||
av_compare_ts(pkt->dts - os->first_dts, st->time_base, |
||||
seg_end_duration, AV_TIME_BASE_Q) >= 0) { |
||||
int64_t prev_duration = c->last_duration; |
||||
|
||||
c->last_duration = av_rescale_q(pkt->dts - os->start_dts, |
||||
st->time_base, |
||||
AV_TIME_BASE_Q); |
||||
c->total_duration = av_rescale_q(pkt->dts - os->first_dts, |
||||
st->time_base, |
||||
AV_TIME_BASE_Q); |
||||
|
||||
if ((!c->use_timeline || !c->use_template) && prev_duration) { |
||||
if (c->last_duration < prev_duration*9/10 || |
||||
c->last_duration > prev_duration*11/10) { |
||||
av_log(s, AV_LOG_WARNING, |
||||
"Segment durations differ too much, enable use_timeline " |
||||
"and use_template, or keep a stricter keyframe interval\n"); |
||||
} |
||||
} |
||||
|
||||
if ((ret = dash_flush(s, 0)) < 0) |
||||
return ret; |
||||
c->nb_segments++; |
||||
} |
||||
|
||||
if (!os->packets_written) |
||||
os->start_dts = pkt->dts; |
||||
os->end_dts = pkt->dts + pkt->duration; |
||||
os->packets_written++; |
||||
return ff_write_chained(os->ctx, 0, pkt, s); |
||||
} |
||||
|
||||
static int dash_write_trailer(AVFormatContext *s) |
||||
{ |
||||
DASHContext *c = s->priv_data; |
||||
|
||||
if (s->nb_streams > 0) { |
||||
OutputStream *os = &c->streams[0]; |
||||
// If no segments have been written so far, try to do a crude
|
||||
// guess of the segment duration
|
||||
if (!c->last_duration) |
||||
c->last_duration = av_rescale_q(os->end_dts - os->start_dts, |
||||
s->streams[0]->time_base, |
||||
AV_TIME_BASE_Q); |
||||
c->total_duration = av_rescale_q(os->end_dts - os->first_dts, |
||||
s->streams[0]->time_base, |
||||
AV_TIME_BASE_Q); |
||||
} |
||||
dash_flush(s, 1); |
||||
|
||||
if (c->remove_at_exit) { |
||||
char filename[1024]; |
||||
int i; |
||||
for (i = 0; i < s->nb_streams; i++) { |
||||
OutputStream *os = &c->streams[i]; |
||||
snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->initfile); |
||||
unlink(filename); |
||||
} |
||||
unlink(s->filename); |
||||
} |
||||
|
||||
dash_free(s); |
||||
return 0; |
||||
} |
||||
|
||||
#define OFFSET(x) offsetof(DASHContext, x) |
||||
#define E AV_OPT_FLAG_ENCODING_PARAM |
||||
static const AVOption options[] = { |
||||
{ "window_size", "number of segments kept in the manifest", OFFSET(window_size), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, E }, |
||||
{ "extra_window_size", "number of segments kept outside of the manifest before removing from disk", OFFSET(extra_window_size), AV_OPT_TYPE_INT, { .i64 = 5 }, 0, INT_MAX, E }, |
||||
{ "min_seg_duration", "minimum segment duration (in microseconds)", OFFSET(min_seg_duration), AV_OPT_TYPE_INT64, { .i64 = 5000000 }, 0, INT_MAX, E }, |
||||
{ "remove_at_exit", "remove all segments when finished", OFFSET(remove_at_exit), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, E }, |
||||
{ "use_template", "Use SegmentTemplate instead of SegmentList", OFFSET(use_template), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E }, |
||||
{ "use_timeline", "Use SegmentTimeline in SegmentTemplate", OFFSET(use_timeline), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E }, |
||||
{ "single_file", "Store all segments in one file, accessed using byte ranges", OFFSET(single_file), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, E }, |
||||
{ NULL }, |
||||
}; |
||||
|
||||
static const AVClass dash_class = { |
||||
.class_name = "dash muxer", |
||||
.item_name = av_default_item_name, |
||||
.option = options, |
||||
.version = LIBAVUTIL_VERSION_INT, |
||||
}; |
||||
|
||||
AVOutputFormat ff_dash_muxer = { |
||||
.name = "dash", |
||||
.long_name = NULL_IF_CONFIG_SMALL("DASH Muxer"), |
||||
.priv_data_size = sizeof(DASHContext), |
||||
.audio_codec = AV_CODEC_ID_AAC, |
||||
.video_codec = AV_CODEC_ID_H264, |
||||
.flags = AVFMT_GLOBALHEADER | AVFMT_NOFILE | AVFMT_TS_NEGATIVE, |
||||
.write_header = dash_write_header, |
||||
.write_packet = dash_write_packet, |
||||
.write_trailer = dash_write_trailer, |
||||
.codec_tag = (const AVCodecTag* const []){ ff_mp4_obj_type, 0 }, |
||||
.priv_class = &dash_class, |
||||
}; |
Loading…
Reference in new issue