+
+bool
+FFmpegDecoder::decode_video_packet ()
+{
+ int frame_finished;
+ if (avcodec_decode_video2 (video_codec_context(), _frame, &frame_finished, &_packet) < 0 || !frame_finished) {
+ return false;
+ }
+
+ boost::mutex::scoped_lock lm (_filter_graphs_mutex);
+
+ shared_ptr<FilterGraph> graph;
+
+ list<shared_ptr<FilterGraph> >::iterator i = _filter_graphs.begin();
+ while (i != _filter_graphs.end() && !(*i)->can_process (libdcp::Size (_frame->width, _frame->height), (AVPixelFormat) _frame->format)) {
+ ++i;
+ }
+
+ if (i == _filter_graphs.end ()) {
+ shared_ptr<const Film> film = _film.lock ();
+ assert (film);
+
+ graph.reset (new FilterGraph (_ffmpeg_content, libdcp::Size (_frame->width, _frame->height), (AVPixelFormat) _frame->format));
+ _filter_graphs.push_back (graph);
+
+ film->log()->log (String::compose (N_("New graph for %1x%2, pixel format %3"), _frame->width, _frame->height, _frame->format));
+ } else {
+ graph = *i;
+ }
+
+ list<shared_ptr<Image> > images = graph->process (_frame);
+
+ string post_process = Filter::ffmpeg_strings (_ffmpeg_content->filters()).second;
+
+ for (list<shared_ptr<Image> >::iterator i = images.begin(); i != images.end(); ++i) {
+
+ shared_ptr<Image> image = *i;
+ if (!post_process.empty ()) {
+ image = image->post_process (post_process, true);
+ }
+
+ int64_t const bet = av_frame_get_best_effort_timestamp (_frame);
+ if (bet != AV_NOPTS_VALUE) {
+
+ double const pts = bet * av_q2d (_format_context->streams[_video_stream]->time_base) - _pts_offset;
+ double const next = _video_position / _ffmpeg_content->video_frame_rate();
+ double const one_frame = 1 / _ffmpeg_content->video_frame_rate ();
+ double delta = pts - next;
+
+ while (delta > one_frame) {
+ /* This PTS is more than one frame forward in time of where we think we should be; emit
+ a black frame.
+ */
+ boost::shared_ptr<Image> black (
+ new SimpleImage (
+ static_cast<AVPixelFormat> (_frame->format),
+ libdcp::Size (video_codec_context()->width, video_codec_context()->height),
+ true
+ )
+ );
+
+ black->make_black ();
+ video (image, false, _video_position);
+ delta -= one_frame;
+ }
+
+ if (delta > -one_frame) {
+ /* This PTS is within a frame of being right; emit this (otherwise it will be dropped) */
+ video (image, false, _video_position);
+ }
+ } else {
+ shared_ptr<const Film> film = _film.lock ();
+ assert (film);
+ film->log()->log ("Dropping frame without PTS");
+ }
+ }
+
+ return true;
+}
+
+
+void
+FFmpegDecoder::setup_subtitle ()
+{
+ boost::mutex::scoped_lock lm (_mutex);
+
+ if (!_ffmpeg_content->subtitle_stream() || _ffmpeg_content->subtitle_stream()->id >= int (_format_context->nb_streams)) {
+ return;
+ }
+
+ _subtitle_codec_context = _format_context->streams[_ffmpeg_content->subtitle_stream()->id]->codec;
+ _subtitle_codec = avcodec_find_decoder (_subtitle_codec_context->codec_id);
+
+ if (_subtitle_codec == 0) {
+ throw DecodeError (_("could not find subtitle decoder"));
+ }
+
+ if (avcodec_open2 (_subtitle_codec_context, _subtitle_codec, 0) < 0) {
+ throw DecodeError (N_("could not open subtitle decoder"));
+ }
+}
+
+bool
+FFmpegDecoder::done () const
+{
+ bool const vd = !_decode_video || (_video_position >= _ffmpeg_content->video_length());
+ bool const ad = !_decode_audio || !_ffmpeg_content->audio_stream() || (_audio_position >= _ffmpeg_content->audio_length());
+ return vd && ad;
+}
+