2 Copyright (C) 2013 Carl Hetherington <cth@carlh.net>
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 #include <libavcodec/avcodec.h>
22 #include <libavformat/avformat.h>
24 #include "ffmpeg_examiner.h"
25 #include "ffmpeg_content.h"
32 using std::stringstream;
33 using boost::shared_ptr;
34 using boost::optional;
36 FFmpegExaminer::FFmpegExaminer (shared_ptr<const FFmpegContent> c)
39 /* Find audio and subtitle streams */
41 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
42 AVStream* s = _format_context->streams[i];
43 if (s->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
45 /* This is a hack; sometimes it seems that _audio_codec_context->channel_layout isn't set up,
46 so bodge it here. No idea why we should have to do this.
49 if (s->codec->channel_layout == 0) {
50 s->codec->channel_layout = av_get_default_channel_layout (s->codec->channels);
53 _audio_streams.push_back (
54 shared_ptr<FFmpegAudioStream> (
55 new FFmpegAudioStream (audio_stream_name (s), s->id, s->codec->sample_rate, s->codec->channels)
59 } else if (s->codec->codec_type == AVMEDIA_TYPE_SUBTITLE) {
60 _subtitle_streams.push_back (shared_ptr<FFmpegSubtitleStream> (new FFmpegSubtitleStream (subtitle_stream_name (s), s->id)));
64 /* Run through until we find the first audio (for each stream) and video */
67 int r = av_read_frame (_format_context, &_packet);
74 AVCodecContext* context = _format_context->streams[_packet.stream_index]->codec;
76 if (_packet.stream_index == _video_stream && !_first_video) {
77 if (avcodec_decode_video2 (context, _frame, &frame_finished, &_packet) >= 0 && frame_finished) {
78 _first_video = frame_time (_format_context->streams[_video_stream]);
81 for (size_t i = 0; i < _audio_streams.size(); ++i) {
82 if (_audio_streams[i]->uses_index (_format_context, _packet.stream_index) && !_audio_streams[i]->first_audio) {
83 if (avcodec_decode_audio4 (context, _frame, &frame_finished, &_packet) >= 0 && frame_finished) {
84 _audio_streams[i]->first_audio = frame_time (_audio_streams[i]->stream (_format_context));
90 bool have_all_audio = true;
92 while (i < _audio_streams.size() && have_all_audio) {
93 have_all_audio = _audio_streams[i]->first_audio;
97 av_free_packet (&_packet);
99 if (_first_video && have_all_audio) {
106 FFmpegExaminer::frame_time (AVStream* s) const
110 int64_t const bet = av_frame_get_best_effort_timestamp (_frame);
111 if (bet != AV_NOPTS_VALUE) {
112 t = bet * av_q2d (s->time_base);
119 FFmpegExaminer::video_frame_rate () const
121 AVStream* s = _format_context->streams[_video_stream];
123 if (s->avg_frame_rate.num && s->avg_frame_rate.den) {
124 return av_q2d (s->avg_frame_rate);
127 return av_q2d (s->r_frame_rate);
131 FFmpegExaminer::video_size () const
133 return libdcp::Size (video_codec_context()->width, video_codec_context()->height);
136 /** @return Length (in video frames) according to our content's header */
138 FFmpegExaminer::video_length () const
140 VideoContent::Frame const length = (double (_format_context->duration) / AV_TIME_BASE) * video_frame_rate();
141 return max (1, length);
145 FFmpegExaminer::audio_stream_name (AVStream* s) const
149 n << stream_name (s);
151 if (!n.str().empty()) {
155 n << s->codec->channels << " channels";
161 FFmpegExaminer::subtitle_stream_name (AVStream* s) const
165 n << stream_name (s);
167 if (n.str().empty()) {
175 FFmpegExaminer::stream_name (AVStream* s) const
180 AVDictionaryEntry const * lang = av_dict_get (s->metadata, "language", 0, 0);
185 AVDictionaryEntry const * title = av_dict_get (s->metadata, "title", 0, 0);
187 if (!n.str().empty()) {