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 "dcpomatic_log.h"
28 #include "ffmpeg_subtitle_stream.h"
29 #include "ffmpeg_audio_stream.h"
31 #include "compose.hpp"
32 #include <dcp/raw_convert.h>
34 #include <libavcodec/avcodec.h>
35 #include <libavformat/avformat.h>
36 #include <libswscale/swscale.h>
38 #include <boost/algorithm/string.hpp>
39 #include <boost/foreach.hpp>
48 using boost::shared_ptr;
49 using boost::optional;
50 using dcp::raw_convert;
52 boost::mutex FFmpeg::_mutex;
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);
101 boost::algorithm::trim (str);
102 dcpomatic_log->log (String::compose ("FFmpeg: %1", str), LogEntry::TYPE_GENERAL);
106 FFmpeg::setup_general ()
108 /* This might not work too well in some cases of multiple FFmpeg decoders,
109 but it's probably good enough.
111 av_log_set_callback (FFmpeg::ffmpeg_log_callback);
113 _file_group.set_paths (_ffmpeg_content->paths ());
114 _avio_buffer = static_cast<uint8_t*> (wrapped_av_malloc (_avio_buffer_size));
115 _avio_context = avio_alloc_context (_avio_buffer, _avio_buffer_size, 0, this, avio_read_wrapper, 0, avio_seek_wrapper);
116 _format_context = avformat_alloc_context ();
117 _format_context->pb = _avio_context;
119 AVDictionary* options = 0;
120 /* These durations are in microseconds, and represent how far into the content file
121 we will look for streams.
123 av_dict_set (&options, "analyzeduration", raw_convert<string> (5 * 60 * 1000000).c_str(), 0);
124 av_dict_set (&options, "probesize", raw_convert<string> (5 * 60 * 1000000).c_str(), 0);
125 if (_ffmpeg_content->decryption_key()) {
126 av_dict_set (&options, "decryption_key", _ffmpeg_content->decryption_key()->c_str(), 0);
129 int e = avformat_open_input (&_format_context, 0, 0, &options);
131 throw OpenFileError (_ffmpeg_content->path(0).string(), e, OpenFileError::READ);
134 if (avformat_find_stream_info (_format_context, 0) < 0) {
135 throw DecodeError (_("could not find stream information"));
138 /* Find video stream */
140 optional<int> video_stream_undefined_frame_rate;
142 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
143 AVStream* s = _format_context->streams[i];
144 if (s->codec->codec_type == AVMEDIA_TYPE_VIDEO && avcodec_find_decoder(s->codec->codec_id)) {
145 if (s->avg_frame_rate.num > 0 && s->avg_frame_rate.den > 0) {
146 /* This is definitely our video stream */
149 /* This is our video stream if we don't get a better offer */
150 video_stream_undefined_frame_rate = i;
155 /* Files from iTunes sometimes have two video streams, one with the avg_frame_rate.num and .den set
156 to zero. Only use such a stream if there is no alternative.
158 if (!_video_stream && video_stream_undefined_frame_rate) {
159 _video_stream = video_stream_undefined_frame_rate.get();
162 /* Ignore video streams with crazy frame rates. These are usually things like album art on MP3s. */
163 if (_video_stream && av_q2d(av_guess_frame_rate(_format_context, _format_context->streams[_video_stream.get()], 0)) > 1000) {
164 _video_stream = optional<int>();
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);
216 /* Enable following of links in files */
217 av_dict_set_int (&options, "enable_drefs", 1, 0);
219 if (avcodec_open2 (context, codec, &options) < 0) {
220 throw DecodeError (N_("could not open decoder"));
223 dcpomatic_log->log (String::compose ("No codec found for stream %1", i), LogEntry::TYPE_WARNING);
229 FFmpeg::video_codec_context () const
231 if (!_video_stream) {
235 return _format_context->streams[_video_stream.get()]->codec;
239 FFmpeg::subtitle_codec_context () const
241 if (!_ffmpeg_content->subtitle_stream ()) {
245 return _ffmpeg_content->subtitle_stream()->stream(_format_context)->codec;
249 FFmpeg::avio_read (uint8_t* buffer, int const amount)
251 return _file_group.read (buffer, amount);
255 FFmpeg::avio_seek (int64_t const pos, int whence)
257 if (whence == AVSEEK_SIZE) {
258 return _file_group.length ();
261 return _file_group.seek (pos, whence);
265 FFmpeg::subtitle_period (AVSubtitle const & sub)
267 ContentTime const packet_time = ContentTime::from_seconds (static_cast<double> (sub.pts) / AV_TIME_BASE);
269 if (sub.end_display_time == static_cast<uint32_t> (-1)) {
270 /* End time is not known */
271 return FFmpegSubtitlePeriod (packet_time + ContentTime::from_seconds (sub.start_display_time / 1e3));
274 return FFmpegSubtitlePeriod (
275 packet_time + ContentTime::from_seconds (sub.start_display_time / 1e3),
276 packet_time + ContentTime::from_seconds (sub.end_display_time / 1e3)
280 /** Compute the pts offset to use given a set of audio streams and some video details.
281 * Sometimes these parameters will have just been determined by an Examiner, sometimes
282 * they will have been retrieved from a piece of Content, hence the need for this method
286 FFmpeg::pts_offset (vector<shared_ptr<FFmpegAudioStream> > audio_streams, optional<ContentTime> first_video, double video_frame_rate) const
288 /* Audio and video frame PTS values may not start with 0. We want
289 to fiddle them so that:
291 1. One of them starts at time 0.
292 2. The first video PTS value ends up on a frame boundary.
294 Then we remove big initial gaps in PTS and we allow our
295 insertion of black frames to work.
298 audio_pts_to_use = audio_pts_from_ffmpeg + pts_offset;
299 video_pts_to_use = video_pts_from_ffmpeg + pts_offset;
302 /* First, make one of them start at 0 */
304 ContentTime po = ContentTime::min ();
307 po = - first_video.get ();
310 BOOST_FOREACH (shared_ptr<FFmpegAudioStream> i, audio_streams) {
311 if (i->first_audio) {
312 po = max (po, - i->first_audio.get ());
316 /* If the offset is positive we would be pushing things from a -ve PTS to be played.
317 I don't think we ever want to do that, as it seems things at -ve PTS are not meant
318 to be seen (use for alignment bars etc.); see mantis #418.
320 if (po > ContentTime ()) {
324 /* Now adjust so that the video pts starts on a frame */
326 ContentTime const fvc = first_video.get() + po;
327 po += fvc.ceil (video_frame_rate) - fvc;