2 Copyright (C) 2013-2019 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"
33 #include <dcp/raw_convert.h>
35 #include <libavcodec/avcodec.h>
36 #include <libavformat/avformat.h>
37 #include <libswscale/swscale.h>
39 #include <boost/algorithm/string.hpp>
48 using std::shared_ptr;
49 using boost::optional;
50 using dcp::raw_convert;
51 using namespace dcpomatic;
53 boost::mutex FFmpeg::_mutex;
55 FFmpeg::FFmpeg (std::shared_ptr<const FFmpegContent> c)
58 , _avio_buffer_size (4096)
69 boost::mutex::scoped_lock lm (_mutex);
71 DCPOMATIC_DISABLE_WARNINGS
72 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
73 avcodec_close (_format_context->streams[i]->codec);
75 DCPOMATIC_ENABLE_WARNINGS
77 av_frame_free (&_frame);
78 avformat_close_input (&_format_context);
82 avio_read_wrapper (void* data, uint8_t* buffer, int amount)
84 return reinterpret_cast<FFmpeg*>(data)->avio_read (buffer, amount);
88 avio_seek_wrapper (void* data, int64_t offset, int whence)
90 return reinterpret_cast<FFmpeg*>(data)->avio_seek (offset, whence);
94 FFmpeg::ffmpeg_log_callback (void* ptr, int level, const char* fmt, va_list vl)
96 if (level > AV_LOG_WARNING) {
101 static int prefix = 0;
102 av_log_format_line (ptr, level, fmt, vl, line, sizeof (line), &prefix);
104 boost::algorithm::trim (str);
105 dcpomatic_log->log (String::compose ("FFmpeg: %1", str), LogEntry::TYPE_GENERAL);
109 FFmpeg::setup_general ()
111 /* This might not work too well in some cases of multiple FFmpeg decoders,
112 but it's probably good enough.
114 av_log_set_callback (FFmpeg::ffmpeg_log_callback);
116 _file_group.set_paths (_ffmpeg_content->paths ());
117 _avio_buffer = static_cast<uint8_t*> (wrapped_av_malloc (_avio_buffer_size));
118 _avio_context = avio_alloc_context (_avio_buffer, _avio_buffer_size, 0, this, avio_read_wrapper, 0, avio_seek_wrapper);
119 if (!_avio_context) {
120 throw std::bad_alloc ();
122 _format_context = avformat_alloc_context ();
123 if (!_format_context) {
124 throw std::bad_alloc ();
126 _format_context->pb = _avio_context;
128 AVDictionary* options = nullptr;
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 DCPOMATIC_DISABLE_WARNINGS
143 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
144 auto s = _format_context->streams[i];
145 if (s->codec->codec_type == AVMEDIA_TYPE_VIDEO && avcodec_find_decoder(s->codec->codec_id)) {
146 if (s->avg_frame_rate.num > 0 && s->avg_frame_rate.den > 0) {
147 /* This is definitely our video stream */
150 /* This is our video stream if we don't get a better offer */
151 video_stream_undefined_frame_rate = i;
155 DCPOMATIC_ENABLE_WARNINGS
157 /* Files from iTunes sometimes have two video streams, one with the avg_frame_rate.num and .den set
158 to zero. Only use such a stream if there is no alternative.
160 if (!_video_stream && video_stream_undefined_frame_rate) {
161 _video_stream = video_stream_undefined_frame_rate.get();
164 /* Ignore video streams with crazy frame rates. These are usually things like album art on MP3s. */
165 if (_video_stream && av_q2d(av_guess_frame_rate(_format_context, _format_context->streams[_video_stream.get()], 0)) > 1000) {
166 _video_stream = optional<int>();
169 /* Hack: if the AVStreams have duplicate IDs, replace them with our
170 own. We use the IDs so that we can cope with VOBs, in which streams
171 move about in index but remain with the same ID in different
172 VOBs. However, some files have duplicate IDs, hence this hack.
175 bool duplicates = false;
176 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
177 for (uint32_t j = i + 1; j < _format_context->nb_streams; ++j) {
178 if (_format_context->streams[i]->id == _format_context->streams[j]->id) {
185 /* Put in our own IDs */
186 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
187 _format_context->streams[i]->id = i;
191 _frame = av_frame_alloc ();
193 throw DecodeError (N_("could not allocate frame"));
198 FFmpeg::setup_decoders ()
200 boost::mutex::scoped_lock lm (_mutex);
202 DCPOMATIC_DISABLE_WARNINGS
203 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
204 auto context = _format_context->streams[i]->codec;
206 AVCodec* codec = avcodec_find_decoder (context->codec_id);
209 AVDictionary* options = nullptr;
210 /* This option disables decoding of DCA frame footers in our patched version
211 of FFmpeg. I believe these footers are of no use to us, and they can cause
212 problems when FFmpeg fails to decode them (mantis #352).
214 av_dict_set (&options, "disable_footer", "1", 0);
215 /* This allows decoding of some DNxHR 444 and HQX files; see
216 https://trac.ffmpeg.org/ticket/5681
218 av_dict_set_int (&options, "strict", FF_COMPLIANCE_EXPERIMENTAL, 0);
219 /* Enable following of links in files */
220 av_dict_set_int (&options, "enable_drefs", 1, 0);
222 if (avcodec_open2 (context, codec, &options) < 0) {
223 throw DecodeError (N_("could not open decoder"));
226 dcpomatic_log->log (String::compose ("No codec found for stream %1", i), LogEntry::TYPE_WARNING);
229 DCPOMATIC_ENABLE_WARNINGS
232 DCPOMATIC_DISABLE_WARNINGS
234 FFmpeg::video_codec_context () const
236 if (!_video_stream) {
240 return _format_context->streams[_video_stream.get()]->codec;
244 FFmpeg::subtitle_codec_context () const
246 if (!_ffmpeg_content->subtitle_stream ()) {
250 return _ffmpeg_content->subtitle_stream()->stream(_format_context)->codec;
252 DCPOMATIC_ENABLE_WARNINGS
255 FFmpeg::avio_read (uint8_t* buffer, int const amount)
257 return _file_group.read (buffer, amount);
261 FFmpeg::avio_seek (int64_t const pos, int whence)
263 if (whence == AVSEEK_SIZE) {
264 return _file_group.length ();
267 return _file_group.seek (pos, whence);
271 FFmpeg::subtitle_period (AVSubtitle const & sub)
273 auto const packet_time = ContentTime::from_seconds (static_cast<double> (sub.pts) / AV_TIME_BASE);
275 if (sub.end_display_time == static_cast<uint32_t> (-1)) {
276 /* End time is not known */
277 return FFmpegSubtitlePeriod (packet_time + ContentTime::from_seconds (sub.start_display_time / 1e3));
280 return FFmpegSubtitlePeriod (
281 packet_time + ContentTime::from_seconds (sub.start_display_time / 1e3),
282 packet_time + ContentTime::from_seconds (sub.end_display_time / 1e3)
286 /** Compute the pts offset to use given a set of audio streams and some video details.
287 * Sometimes these parameters will have just been determined by an Examiner, sometimes
288 * they will have been retrieved from a piece of Content, hence the need for this method
292 FFmpeg::pts_offset (vector<shared_ptr<FFmpegAudioStream>> audio_streams, optional<ContentTime> first_video, double video_frame_rate) const
294 /* Audio and video frame PTS values may not start with 0. We want
295 to fiddle them so that:
297 1. One of them starts at time 0.
298 2. The first video PTS value ends up on a frame boundary.
300 Then we remove big initial gaps in PTS and we allow our
301 insertion of black frames to work.
304 audio_pts_to_use = audio_pts_from_ffmpeg + pts_offset;
305 video_pts_to_use = video_pts_from_ffmpeg + pts_offset;
308 /* First, make one of them start at 0 */
310 auto po = ContentTime::min ();
313 po = - first_video.get ();
316 for (auto i: audio_streams) {
317 if (i->first_audio) {
318 po = max (po, - i->first_audio.get ());
322 /* If the offset is positive we would be pushing things from a -ve PTS to be played.
323 I don't think we ever want to do that, as it seems things at -ve PTS are not meant
324 to be seen (use for alignment bars etc.); see mantis #418.
326 if (po > ContentTime ()) {
330 /* Now adjust so that the video pts starts on a frame */
332 auto const fvc = first_video.get() + po;
333 po += fvc.ceil (video_frame_rate) - fvc;