2 Copyright (C) 2013-2021 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/>.
23 #include "ffmpeg_content.h"
25 #include "exceptions.h"
28 #include "dcpomatic_log.h"
29 #include "ffmpeg_subtitle_stream.h"
30 #include "ffmpeg_audio_stream.h"
32 #include "compose.hpp"
34 #include <dcp/raw_convert.h>
36 #include <libavcodec/avcodec.h>
37 #include <libavformat/avformat.h>
38 #include <libswscale/swscale.h>
40 #include <boost/algorithm/string.hpp>
50 using std::shared_ptr;
51 using boost::optional;
52 using dcp::raw_convert;
53 using namespace dcpomatic;
56 boost::mutex FFmpeg::_mutex;
59 FFmpeg::FFmpeg (std::shared_ptr<const FFmpegContent> c)
69 boost::mutex::scoped_lock lm (_mutex);
71 for (auto& i: _codec_context) {
72 avcodec_free_context (&i);
75 av_frame_free (&_video_frame);
76 for (auto& audio_frame: _audio_frame) {
77 av_frame_free (&audio_frame.second);
80 avformat_close_input (&_format_context);
85 avio_read_wrapper (void* data, uint8_t* buffer, int amount)
87 return reinterpret_cast<FFmpeg*>(data)->avio_read (buffer, amount);
92 avio_seek_wrapper (void* data, int64_t offset, int whence)
94 return reinterpret_cast<FFmpeg*>(data)->avio_seek (offset, whence);
99 FFmpeg::ffmpeg_log_callback (void* ptr, int level, const char* fmt, va_list vl)
101 if (level > AV_LOG_WARNING) {
106 static int prefix = 0;
107 av_log_format_line (ptr, level, fmt, vl, line, sizeof (line), &prefix);
109 boost::algorithm::trim (str);
110 dcpomatic_log->log (String::compose ("FFmpeg: %1", str), LogEntry::TYPE_GENERAL);
115 FFmpeg::setup_general ()
117 /* This might not work too well in some cases of multiple FFmpeg decoders,
118 but it's probably good enough.
120 av_log_set_callback (FFmpeg::ffmpeg_log_callback);
122 _file_group.set_paths (_ffmpeg_content->paths ());
123 _avio_buffer = static_cast<uint8_t*> (wrapped_av_malloc(_avio_buffer_size));
124 _avio_context = avio_alloc_context (_avio_buffer, _avio_buffer_size, 0, this, avio_read_wrapper, 0, avio_seek_wrapper);
125 if (!_avio_context) {
126 throw std::bad_alloc ();
128 _format_context = avformat_alloc_context ();
129 if (!_format_context) {
130 throw std::bad_alloc ();
132 _format_context->pb = _avio_context;
134 AVDictionary* options = nullptr;
135 int e = avformat_open_input (&_format_context, 0, 0, &options);
137 throw OpenFileError (_ffmpeg_content->path(0).string(), e, OpenFileError::READ);
140 if (avformat_find_stream_info (_format_context, 0) < 0) {
141 throw DecodeError (_("could not find stream information"));
144 /* Find video stream */
146 optional<int> video_stream_undefined_frame_rate;
148 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
149 auto s = _format_context->streams[i];
150 if (s->codecpar->codec_type == AVMEDIA_TYPE_VIDEO && avcodec_find_decoder(s->codecpar->codec_id)) {
151 if (s->avg_frame_rate.num > 0 && s->avg_frame_rate.den > 0) {
152 /* This is definitely our video stream */
155 /* This is our video stream if we don't get a better offer */
156 video_stream_undefined_frame_rate = i;
161 /* Files from iTunes sometimes have two video streams, one with the avg_frame_rate.num and .den set
162 to zero. Only use such a stream if there is no alternative.
164 if (!_video_stream && video_stream_undefined_frame_rate) {
165 _video_stream = video_stream_undefined_frame_rate.get();
168 /* Ignore video streams with crazy frame rates. These are usually things like album art on MP3s. */
169 if (_video_stream && av_q2d(av_guess_frame_rate(_format_context, _format_context->streams[_video_stream.get()], 0)) > 1000) {
170 _video_stream = optional<int>();
173 /* Hack: if the AVStreams have duplicate IDs, replace them with our
174 own. We use the IDs so that we can cope with VOBs, in which streams
175 move about in index but remain with the same ID in different
176 VOBs. However, some files have duplicate IDs, hence this hack.
179 bool duplicates = false;
180 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
181 for (uint32_t j = i + 1; j < _format_context->nb_streams; ++j) {
182 if (_format_context->streams[i]->id == _format_context->streams[j]->id) {
189 /* Put in our own IDs */
190 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
191 _format_context->streams[i]->id = i;
195 _video_frame = av_frame_alloc ();
196 if (_video_frame == nullptr) {
197 throw std::bad_alloc ();
203 FFmpeg::setup_decoders ()
205 boost::mutex::scoped_lock lm (_mutex);
207 _codec_context.resize (_format_context->nb_streams);
208 for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
209 auto codec = avcodec_find_decoder (_format_context->streams[i]->codecpar->codec_id);
211 auto context = avcodec_alloc_context3 (codec);
213 throw std::bad_alloc ();
215 _codec_context[i] = context;
217 int r = avcodec_parameters_to_context (context, _format_context->streams[i]->codecpar);
219 throw DecodeError ("avcodec_parameters_to_context", "FFmpeg::setup_decoders", r);
222 context->thread_count = 8;
223 context->thread_type = FF_THREAD_FRAME | FF_THREAD_SLICE;
225 AVDictionary* options = nullptr;
226 /* This option disables decoding of DCA frame footers in our patched version
227 of FFmpeg. I believe these footers are of no use to us, and they can cause
228 problems when FFmpeg fails to decode them (mantis #352).
230 av_dict_set (&options, "disable_footer", "1", 0);
231 /* This allows decoding of some DNxHR 444 and HQX files; see
232 https://trac.ffmpeg.org/ticket/5681
234 av_dict_set_int (&options, "strict", FF_COMPLIANCE_EXPERIMENTAL, 0);
235 /* Enable following of links in files */
236 av_dict_set_int (&options, "enable_drefs", 1, 0);
238 r = avcodec_open2 (context, codec, &options);
240 throw DecodeError (N_("avcodec_open2"), N_("FFmpeg::setup_decoders"), r);
243 dcpomatic_log->log (String::compose ("No codec found for stream %1", i), LogEntry::TYPE_WARNING);
250 FFmpeg::video_codec_context () const
252 if (!_video_stream) {
256 return _codec_context[_video_stream.get()];
261 FFmpeg::subtitle_codec_context () const
263 auto str = _ffmpeg_content->subtitle_stream();
268 return _codec_context[str->index(_format_context)];
273 FFmpeg::avio_read (uint8_t* buffer, int const amount)
275 return _file_group.read (buffer, amount);
280 FFmpeg::avio_seek (int64_t const pos, int whence)
282 if (whence == AVSEEK_SIZE) {
283 return _file_group.length ();
286 return _file_group.seek (pos, whence);
291 FFmpeg::subtitle_period (AVPacket const* packet, AVStream const* stream, AVSubtitle const & sub)
293 auto const packet_time = ContentTime::from_seconds (packet->pts * av_q2d(stream->time_base));
294 auto const start = packet_time + ContentTime::from_seconds(sub.start_display_time / 1e3);
296 if (sub.end_display_time == 0 || sub.end_display_time == static_cast<uint32_t>(-1)) {
297 /* End time is not in the AVSubtitle; perhaps we can use the AVPacket's duration */
298 if (packet->duration) {
299 return FFmpegSubtitlePeriod(start, start + ContentTime::from_seconds(packet->duration * av_q2d(stream->time_base)));
301 return FFmpegSubtitlePeriod(start);
305 return FFmpegSubtitlePeriod (start, packet_time + ContentTime::from_seconds(sub.end_display_time / 1e3));
309 /** Compute the pts offset to use given a set of audio streams and some video details.
310 * Sometimes these parameters will have just been determined by an Examiner, sometimes
311 * they will have been retrieved from a piece of Content, hence the need for this method
315 FFmpeg::pts_offset (vector<shared_ptr<FFmpegAudioStream>> audio_streams, optional<ContentTime> first_video, double video_frame_rate) const
317 /* Audio and video frame PTS values may not start with 0. We want
318 to fiddle them so that:
320 1. One of them starts at time 0.
321 2. The first video PTS value ends up on a frame boundary.
323 Then we remove big initial gaps in PTS and we allow our
324 insertion of black frames to work.
327 audio_pts_to_use = audio_pts_from_ffmpeg + pts_offset;
328 video_pts_to_use = video_pts_from_ffmpeg + pts_offset;
331 /* First, make one of them start at 0 */
333 auto po = ContentTime::min ();
336 po = - first_video.get ();
339 for (auto i: audio_streams) {
340 if (i->first_audio) {
341 po = max (po, - i->first_audio.get ());
345 /* If the offset is positive we would be pushing things from a -ve PTS to be played.
346 I don't think we ever want to do that, as it seems things at -ve PTS are not meant
347 to be seen (use for alignment bars etc.); see mantis #418.
349 if (po > ContentTime ()) {
353 /* Now adjust so that the video pts starts on a frame */
355 auto const fvc = first_video.get() + po;
356 po += fvc.ceil (video_frame_rate) - fvc;
364 FFmpeg::audio_frame (shared_ptr<const FFmpegAudioStream> stream)
366 auto iter = _audio_frame.find(stream);
367 if (iter != _audio_frame.end()) {
371 auto frame = av_frame_alloc ();
372 if (frame == nullptr) {
373 throw std::bad_alloc();
376 _audio_frame[stream] = frame;