2 Copyright (C) 2013-2016 Carl Hetherington <cth@carlh.net>
4 This file is part of DCP-o-matic.
6 DCP-o-matic is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 DCP-o-matic is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with DCP-o-matic. If not, see <http://www.gnu.org/licenses/>.
22 #include "ffmpeg_content.h"
24 #include "exceptions.h"
27 #include "ffmpeg_subtitle_stream.h"
28 #include "ffmpeg_audio_stream.h"
30 #include "compose.hpp"
31 #include <dcp/raw_convert.h>
33 #include <libavcodec/avcodec.h>
34 #include <libavformat/avformat.h>
35 #include <libswscale/swscale.h>
37 #include <boost/algorithm/string.hpp>
38 #include <boost/foreach.hpp>
47 using boost::shared_ptr;
48 using boost::optional;
49 using dcp::raw_convert;
51 boost::mutex FFmpeg::_mutex;
52 boost::weak_ptr<Log> FFmpeg::_ffmpeg_log;
54 FFmpeg::FFmpeg (boost::shared_ptr<const FFmpegContent> c)
57 , _avio_buffer_size (4096)
68 boost::mutex::scoped_lock lm (_mutex);
70 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
71 avcodec_close (_format_context->streams[i]->codec);
74 av_frame_free (&_frame);
75 avformat_close_input (&_format_context);
79 avio_read_wrapper (void* data, uint8_t* buffer, int amount)
81 return reinterpret_cast<FFmpeg*>(data)->avio_read (buffer, amount);
85 avio_seek_wrapper (void* data, int64_t offset, int whence)
87 return reinterpret_cast<FFmpeg*>(data)->avio_seek (offset, whence);
91 FFmpeg::ffmpeg_log_callback (void* ptr, int level, const char* fmt, va_list vl)
93 if (level > AV_LOG_WARNING) {
98 static int prefix = 0;
99 av_log_format_line (ptr, level, fmt, vl, line, sizeof (line), &prefix);
100 shared_ptr<Log> log = _ffmpeg_log.lock ();
103 boost::algorithm::trim (str);
104 log->log (String::compose ("FFmpeg: %1", str), LogEntry::TYPE_GENERAL);
111 FFmpeg::setup_general ()
113 /* This might not work too well in some cases of multiple FFmpeg decoders,
114 but it's probably good enough.
116 av_log_set_callback (FFmpeg::ffmpeg_log_callback);
118 _file_group.set_paths (_ffmpeg_content->paths ());
119 _avio_buffer = static_cast<uint8_t*> (wrapped_av_malloc (_avio_buffer_size));
120 _avio_context = avio_alloc_context (_avio_buffer, _avio_buffer_size, 0, this, avio_read_wrapper, 0, avio_seek_wrapper);
121 _format_context = avformat_alloc_context ();
122 _format_context->pb = _avio_context;
124 AVDictionary* options = 0;
125 /* These durations are in microseconds, and represent how far into the content file
126 we will look for streams.
128 av_dict_set (&options, "analyzeduration", raw_convert<string> (5 * 60 * 1000000).c_str(), 0);
129 av_dict_set (&options, "probesize", raw_convert<string> (5 * 60 * 1000000).c_str(), 0);
130 if (_ffmpeg_content->decryption_key()) {
131 av_dict_set (&options, "decryption_key", _ffmpeg_content->decryption_key()->c_str(), 0);
134 int e = avformat_open_input (&_format_context, 0, 0, &options);
136 throw OpenFileError (_ffmpeg_content->path(0).string(), e, true);
139 if (avformat_find_stream_info (_format_context, 0) < 0) {
140 throw DecodeError (_("could not find stream information"));
143 /* Find video stream */
145 optional<int> video_stream_undefined_frame_rate;
147 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
148 AVStream* s = _format_context->streams[i];
149 if (s->codec->codec_type == AVMEDIA_TYPE_VIDEO && avcodec_find_decoder(s->codec->codec_id)) {
150 if (s->avg_frame_rate.num > 0 && s->avg_frame_rate.den > 0) {
151 /* This is definitely our video stream */
154 /* This is our video stream if we don't get a better offer */
155 video_stream_undefined_frame_rate = i;
160 /* Files from iTunes sometimes have two video streams, one with the avg_frame_rate.num and .den set
161 to zero. Only use such a stream if there is no alternative.
163 if (!_video_stream && video_stream_undefined_frame_rate) {
164 _video_stream = video_stream_undefined_frame_rate.get();
167 /* Hack: if the AVStreams have duplicate IDs, replace them with our
168 own. We use the IDs so that we can cope with VOBs, in which streams
169 move about in index but remain with the same ID in different
170 VOBs. However, some files have duplicate IDs, hence this hack.
173 bool duplicates = false;
174 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
175 for (uint32_t j = i + 1; j < _format_context->nb_streams; ++j) {
176 if (_format_context->streams[i]->id == _format_context->streams[j]->id) {
183 /* Put in our own IDs */
184 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
185 _format_context->streams[i]->id = i;
189 _frame = av_frame_alloc ();
191 throw DecodeError (N_("could not allocate frame"));
196 FFmpeg::setup_decoders ()
198 boost::mutex::scoped_lock lm (_mutex);
200 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
201 AVCodecContext* context = _format_context->streams[i]->codec;
203 AVCodec* codec = avcodec_find_decoder (context->codec_id);
206 AVDictionary* options = 0;
207 /* This option disables decoding of DCA frame footers in our patched version
208 of FFmpeg. I believe these footers are of no use to us, and they can cause
209 problems when FFmpeg fails to decode them (mantis #352).
211 av_dict_set (&options, "disable_footer", "1", 0);
212 /* This allows decoding of some DNxHR 444 and HQX files; see
213 https://trac.ffmpeg.org/ticket/5681
215 av_dict_set_int (&options, "strict", FF_COMPLIANCE_EXPERIMENTAL, 0);
217 if (avcodec_open2 (context, codec, &options) < 0) {
218 throw DecodeError (N_("could not open decoder"));
221 dcpomatic_log->log (String::compose ("No codec found for stream %1", i), LogEntry::TYPE_WARNING);
227 FFmpeg::video_codec_context () const
229 if (!_video_stream) {
233 return _format_context->streams[_video_stream.get()]->codec;
237 FFmpeg::subtitle_codec_context () const
239 if (!_ffmpeg_content->subtitle_stream ()) {
243 return _ffmpeg_content->subtitle_stream()->stream(_format_context)->codec;
247 FFmpeg::avio_read (uint8_t* buffer, int const amount)
249 return _file_group.read (buffer, amount);
253 FFmpeg::avio_seek (int64_t const pos, int whence)
255 if (whence == AVSEEK_SIZE) {
256 return _file_group.length ();
259 return _file_group.seek (pos, whence);
263 FFmpeg::subtitle_period (AVSubtitle const & sub)
265 ContentTime const packet_time = ContentTime::from_seconds (static_cast<double> (sub.pts) / AV_TIME_BASE);
267 if (sub.end_display_time == static_cast<uint32_t> (-1)) {
268 /* End time is not known */
269 return FFmpegSubtitlePeriod (packet_time + ContentTime::from_seconds (sub.start_display_time / 1e3));
272 return FFmpegSubtitlePeriod (
273 packet_time + ContentTime::from_seconds (sub.start_display_time / 1e3),
274 packet_time + ContentTime::from_seconds (sub.end_display_time / 1e3)
278 /** Compute the pts offset to use given a set of audio streams and some video details.
279 * Sometimes these parameters will have just been determined by an Examiner, sometimes
280 * they will have been retrieved from a piece of Content, hence the need for this method
284 FFmpeg::pts_offset (vector<shared_ptr<FFmpegAudioStream> > audio_streams, optional<ContentTime> first_video, double video_frame_rate) const
286 /* Audio and video frame PTS values may not start with 0. We want
287 to fiddle them so that:
289 1. One of them starts at time 0.
290 2. The first video PTS value ends up on a frame boundary.
292 Then we remove big initial gaps in PTS and we allow our
293 insertion of black frames to work.
296 audio_pts_to_use = audio_pts_from_ffmpeg + pts_offset;
297 video_pts_to_use = video_pts_from_ffmpeg + pts_offset;
300 /* First, make one of them start at 0 */
302 ContentTime po = ContentTime::min ();
305 po = - first_video.get ();
308 BOOST_FOREACH (shared_ptr<FFmpegAudioStream> i, audio_streams) {
309 if (i->first_audio) {
310 po = max (po, - i->first_audio.get ());
314 /* If the offset is positive we would be pushing things from a -ve PTS to be played.
315 I don't think we ever want to do that, as it seems things at -ve PTS are not meant
316 to be seen (use for alignment bars etc.); see mantis #418.
318 if (po > ContentTime ()) {
322 /* Now adjust so that the video pts starts on a frame */
324 ContentTime const fvc = first_video.get() + po;
325 po += fvc.ceil (video_frame_rate) - fvc;