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, true);
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 /* Hack: if the AVStreams have duplicate IDs, replace them with our
163 own. We use the IDs so that we can cope with VOBs, in which streams
164 move about in index but remain with the same ID in different
165 VOBs. However, some files have duplicate IDs, hence this hack.
168 bool duplicates = false;
169 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
170 for (uint32_t j = i + 1; j < _format_context->nb_streams; ++j) {
171 if (_format_context->streams[i]->id == _format_context->streams[j]->id) {
178 /* Put in our own IDs */
179 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
180 _format_context->streams[i]->id = i;
184 _frame = av_frame_alloc ();
186 throw DecodeError (N_("could not allocate frame"));
191 FFmpeg::setup_decoders ()
193 boost::mutex::scoped_lock lm (_mutex);
195 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
196 AVCodecContext* context = _format_context->streams[i]->codec;
198 AVCodec* codec = avcodec_find_decoder (context->codec_id);
201 AVDictionary* options = 0;
202 /* This option disables decoding of DCA frame footers in our patched version
203 of FFmpeg. I believe these footers are of no use to us, and they can cause
204 problems when FFmpeg fails to decode them (mantis #352).
206 av_dict_set (&options, "disable_footer", "1", 0);
207 /* This allows decoding of some DNxHR 444 and HQX files; see
208 https://trac.ffmpeg.org/ticket/5681
210 av_dict_set_int (&options, "strict", FF_COMPLIANCE_EXPERIMENTAL, 0);
211 /* Enable following of links in files */
212 av_dict_set_int (&options, "enable_drefs", 1, 0);
214 if (avcodec_open2 (context, codec, &options) < 0) {
215 throw DecodeError (N_("could not open decoder"));
218 dcpomatic_log->log (String::compose ("No codec found for stream %1", i), LogEntry::TYPE_WARNING);
224 FFmpeg::video_codec_context () const
226 if (!_video_stream) {
230 return _format_context->streams[_video_stream.get()]->codec;
234 FFmpeg::subtitle_codec_context () const
236 if (!_ffmpeg_content->subtitle_stream ()) {
240 return _ffmpeg_content->subtitle_stream()->stream(_format_context)->codec;
244 FFmpeg::avio_read (uint8_t* buffer, int const amount)
246 return _file_group.read (buffer, amount);
250 FFmpeg::avio_seek (int64_t const pos, int whence)
252 if (whence == AVSEEK_SIZE) {
253 return _file_group.length ();
256 return _file_group.seek (pos, whence);
260 FFmpeg::subtitle_period (AVSubtitle const & sub)
262 ContentTime const packet_time = ContentTime::from_seconds (static_cast<double> (sub.pts) / AV_TIME_BASE);
264 if (sub.end_display_time == static_cast<uint32_t> (-1)) {
265 /* End time is not known */
266 return FFmpegSubtitlePeriod (packet_time + ContentTime::from_seconds (sub.start_display_time / 1e3));
269 return FFmpegSubtitlePeriod (
270 packet_time + ContentTime::from_seconds (sub.start_display_time / 1e3),
271 packet_time + ContentTime::from_seconds (sub.end_display_time / 1e3)
275 /** Compute the pts offset to use given a set of audio streams and some video details.
276 * Sometimes these parameters will have just been determined by an Examiner, sometimes
277 * they will have been retrieved from a piece of Content, hence the need for this method
281 FFmpeg::pts_offset (vector<shared_ptr<FFmpegAudioStream> > audio_streams, optional<ContentTime> first_video, double video_frame_rate) const
283 /* Audio and video frame PTS values may not start with 0. We want
284 to fiddle them so that:
286 1. One of them starts at time 0.
287 2. The first video PTS value ends up on a frame boundary.
289 Then we remove big initial gaps in PTS and we allow our
290 insertion of black frames to work.
293 audio_pts_to_use = audio_pts_from_ffmpeg + pts_offset;
294 video_pts_to_use = video_pts_from_ffmpeg + pts_offset;
297 /* First, make one of them start at 0 */
299 ContentTime po = ContentTime::min ();
302 po = - first_video.get ();
305 BOOST_FOREACH (shared_ptr<FFmpegAudioStream> i, audio_streams) {
306 if (i->first_audio) {
307 po = max (po, - i->first_audio.get ());
311 /* If the offset is positive we would be pushing things from a -ve PTS to be played.
312 I don't think we ever want to do that, as it seems things at -ve PTS are not meant
313 to be seen (use for alignment bars etc.); see mantis #418.
315 if (po > ContentTime ()) {
319 /* Now adjust so that the video pts starts on a frame */
321 ContentTime const fvc = first_video.get() + po;
322 po += fvc.ceil (video_frame_rate) - fvc;