Various markup and tweaks.
[dcpomatic.git] / src / lib / ffmpeg_decoder.cc
index bfb0ed568ca2a3877341df5fd67fcf877803c7d8..8834f28ed1c4f90152589bc2f200a9b4c49b9069 100644 (file)
@@ -47,19 +47,27 @@ extern "C" {
 #include "util.h"
 #include "log.h"
 #include "ffmpeg_decoder.h"
+#include "filter_graph.h"
 #include "subtitle.h"
 
+#include "i18n.h"
+
+using std::cout;
 using std::string;
 using std::vector;
 using std::stringstream;
+using std::list;
 using boost::shared_ptr;
-
-FFmpegDecoder::FFmpegDecoder (shared_ptr<Film> f, shared_ptr<const Options> o, Job* j, bool minimal, bool ignore_length)
-       : Decoder (f, o, j, minimal, ignore_length)
+using boost::optional;
+using boost::dynamic_pointer_cast;
+using libdcp::Size;
+
+FFmpegDecoder::FFmpegDecoder (shared_ptr<Film> f, DecodeOptions o)
+       : Decoder (f, o)
+       , VideoDecoder (f, o)
+       , AudioDecoder (f, o)
        , _format_context (0)
        , _video_stream (-1)
-       , _audio_stream (-1)
-       , _subtitle_stream (-1)
        , _frame (0)
        , _video_codec_context (0)
        , _video_codec (0)
@@ -72,6 +80,10 @@ FFmpegDecoder::FFmpegDecoder (shared_ptr<Film> f, shared_ptr<const Options> o, J
        setup_video ();
        setup_audio ();
        setup_subtitle ();
+
+       if (!o.video_sync) {
+               _first_video = 0;
+       }
 }
 
 FFmpegDecoder::~FFmpegDecoder ()
@@ -87,24 +99,23 @@ FFmpegDecoder::~FFmpegDecoder ()
        if (_subtitle_codec_context) {
                avcodec_close (_subtitle_codec_context);
        }
-       
+
        av_free (_frame);
+       
        avformat_close_input (&_format_context);
 }      
 
 void
 FFmpegDecoder::setup_general ()
 {
-       int r;
-       
        av_register_all ();
 
-       if ((r = avformat_open_input (&_format_context, _film->content_path().c_str(), 0, 0)) != 0) {
+       if (avformat_open_input (&_format_context, _film->content_path().c_str(), 0, 0) < 0) {
                throw OpenFileError (_film->content_path ());
        }
 
        if (avformat_find_stream_info (_format_context, 0) < 0) {
-               throw DecodeError ("could not find stream information");
+               throw DecodeError (_("could not find stream information"));
        }
 
        /* Find video, audio and subtitle streams and choose the first of each */
@@ -114,35 +125,37 @@ FFmpegDecoder::setup_general ()
                if (s->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
                        _video_stream = i;
                } else if (s->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
-                       if (_audio_stream == -1) {
-                               _audio_stream = i;
+
+                       /* This is a hack; sometimes it seems that _audio_codec_context->channel_layout isn't set up,
+                          so bodge it here.  No idea why we should have to do this.
+                       */
+
+                       if (s->codec->channel_layout == 0) {
+                               s->codec->channel_layout = av_get_default_channel_layout (s->codec->channels);
                        }
-                       _audio_streams.push_back (AudioStream (stream_name (s), i, s->codec->channels));
+                       
+                       _audio_streams.push_back (
+                               shared_ptr<AudioStream> (
+                                       new FFmpegAudioStream (stream_name (s), i, s->codec->sample_rate, s->codec->channel_layout)
+                                       )
+                               );
+                       
                } else if (s->codec->codec_type == AVMEDIA_TYPE_SUBTITLE) {
-                       if (_subtitle_stream == -1) {
-                               _subtitle_stream = i;
-                       }
-                       _subtitle_streams.push_back (SubtitleStream (stream_name (s), i));
+                       _subtitle_streams.push_back (
+                               shared_ptr<SubtitleStream> (
+                                       new SubtitleStream (stream_name (s), i)
+                                       )
+                               );
                }
        }
 
-       /* Now override audio and subtitle streams with those from the Film, if it has any */
-
-       if (_film->audio_stream_index() != -1) {
-               _audio_stream = _film->audio_stream().id();
-       }
-
-       if (_film->subtitle_stream_index() != -1) {
-               _subtitle_stream = _film->subtitle_stream().id ();
-       }
-
        if (_video_stream < 0) {
-               throw DecodeError ("could not find video stream");
+               throw DecodeError (N_("could not find video stream"));
        }
 
        _frame = avcodec_alloc_frame ();
        if (_frame == 0) {
-               throw DecodeError ("could not allocate frame");
+               throw DecodeError (N_("could not allocate frame"));
        }
 }
 
@@ -153,76 +166,67 @@ FFmpegDecoder::setup_video ()
        _video_codec = avcodec_find_decoder (_video_codec_context->codec_id);
 
        if (_video_codec == 0) {
-               throw DecodeError ("could not find video decoder");
+               throw DecodeError (_("could not find video decoder"));
        }
 
-       /* I think this prevents problems with green hash on decodes and
-          "changing frame properties on the fly is not supported by all filters"
-          messages with some content.  Although I'm not sure; needs checking.
-       */
-       AVDictionary* opts = 0;
-       av_dict_set (&opts, "threads", "1", 0);
-       
-       if (avcodec_open2 (_video_codec_context, _video_codec, &opts) < 0) {
-               throw DecodeError ("could not open video decoder");
+       if (avcodec_open2 (_video_codec_context, _video_codec, 0) < 0) {
+               throw DecodeError (N_("could not open video decoder"));
        }
 }
 
 void
 FFmpegDecoder::setup_audio ()
 {
-       if (_audio_stream < 0) {
+       if (!_audio_stream) {
                return;
        }
+
+       shared_ptr<FFmpegAudioStream> ffa = dynamic_pointer_cast<FFmpegAudioStream> (_audio_stream);
+       assert (ffa);
        
-       _audio_codec_context = _format_context->streams[_audio_stream]->codec;
+       _audio_codec_context = _format_context->streams[ffa->id()]->codec;
        _audio_codec = avcodec_find_decoder (_audio_codec_context->codec_id);
 
        if (_audio_codec == 0) {
-               throw DecodeError ("could not find audio decoder");
+               throw DecodeError (_("could not find audio decoder"));
        }
 
        if (avcodec_open2 (_audio_codec_context, _audio_codec, 0) < 0) {
-               throw DecodeError ("could not open audio decoder");
-       }
-
-       /* This is a hack; sometimes it seems that _audio_codec_context->channel_layout isn't set up,
-          so bodge it here.  No idea why we should have to do this.
-       */
-
-       if (_audio_codec_context->channel_layout == 0) {
-               _audio_codec_context->channel_layout = av_get_default_channel_layout (audio_channels ());
+               throw DecodeError (N_("could not open audio decoder"));
        }
 }
 
 void
 FFmpegDecoder::setup_subtitle ()
 {
-       if (_subtitle_stream < 0) {
+       if (!_subtitle_stream) {
                return;
        }
 
-       _subtitle_codec_context = _format_context->streams[_subtitle_stream]->codec;
+       _subtitle_codec_context = _format_context->streams[_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");
+               throw DecodeError (_("could not find subtitle decoder"));
        }
        
        if (avcodec_open2 (_subtitle_codec_context, _subtitle_codec, 0) < 0) {
-               throw DecodeError ("could not open subtitle decoder");
+               throw DecodeError (N_("could not open subtitle decoder"));
        }
 }
 
 
 bool
-FFmpegDecoder::do_pass ()
+FFmpegDecoder::pass ()
 {
        int r = av_read_frame (_format_context, &_packet);
        
        if (r < 0) {
                if (r != AVERROR_EOF) {
-                       throw DecodeError ("error on av_read_frame");
+                       /* Maybe we should fail here, but for now we'll just finish off instead */
+                       char buf[256];
+                       av_strerror (r, buf, sizeof(buf));
+                       _film->log()->log (String::compose (N_("error on av_read_frame (%1) (%2)"), buf, r));
                }
                
                /* Get any remaining frames */
@@ -235,84 +239,94 @@ FFmpegDecoder::do_pass ()
                int frame_finished;
 
                while (avcodec_decode_video2 (_video_codec_context, _frame, &frame_finished, &_packet) >= 0 && frame_finished) {
-                       process_video (_frame);
+                       filter_and_emit_video (_frame);
                }
 
-               if (_audio_stream >= 0 && _opt->decode_audio) {
+               if (_audio_stream && _opt.decode_audio) {
                        while (avcodec_decode_audio4 (_audio_codec_context, _frame, &frame_finished, &_packet) >= 0 && frame_finished) {
                                int const data_size = av_samples_get_buffer_size (
                                        0, _audio_codec_context->channels, _frame->nb_samples, audio_sample_format (), 1
                                        );
 
                                assert (_audio_codec_context->channels == _film->audio_channels());
-                               process_audio (_frame->data[0], data_size);
+                               Audio (deinterleave_audio (_frame->data, data_size));
                        }
                }
 
                return true;
        }
 
-       double const pts_seconds = av_q2d (_format_context->streams[_packet.stream_index]->time_base) * _packet.pts;
-       
+       avcodec_get_frame_defaults (_frame);
+
+       shared_ptr<FFmpegAudioStream> ffa = dynamic_pointer_cast<FFmpegAudioStream> (_audio_stream);
+
        if (_packet.stream_index == _video_stream) {
 
-               if (!_first_video) {
-                       _first_video = pts_seconds;
-               }
-               
                int frame_finished;
-               if (avcodec_decode_video2 (_video_codec_context, _frame, &frame_finished, &_packet) >= 0 && frame_finished) {
-                       process_video (_frame);
-               }
+               int const r = avcodec_decode_video2 (_video_codec_context, _frame, &frame_finished, &_packet);
+               if (r >= 0 && frame_finished) {
 
-       } else if (_audio_stream >= 0 && _packet.stream_index == _audio_stream && _opt->decode_audio && _first_video && _first_video.get() <= pts_seconds) {
+                       if (r != _packet.size) {
+                               _film->log()->log (String::compose (N_("Used only %1 bytes of %2 in packet"), r, _packet.size));
+                       }
 
-               /* Note: We only decode audio if we've had our first video packet through, and if it
-                  was before this packet.  Until then audio is thrown away.
-               */
-               
-               if (!_first_audio) {
-                       _first_audio = pts_seconds;
-                       
-                       /* This is our first audio packet, and if we've arrived here we must have had our
-                          first video packet.  Push some silence to make up the gap between our first
-                          video packet and our first audio.
-                       */
-                       
-                       /* frames of silence that we must push */
-                       int const s = rint ((_first_audio.get() - _first_video.get()) * audio_sample_rate ());
-                       
-                       _film->log()->log (
-                               String::compose (
-                                       "First video at %1, first audio at %2, pushing %3 frames of silence for %4 channels (%5 bytes per sample)",
-                                       _first_video.get(), _first_audio.get(), s, audio_channels(), bytes_per_audio_sample()
-                                       )
-                               );
-                       
-                       /* hence bytes */
-                       int const b = s * audio_channels() * bytes_per_audio_sample();
-                       
-                       /* XXX: this assumes that it won't be too much, and there are shaky assumptions
-                          that all sound representations are silent with memset()ed zero data.
-                       */
-                       uint8_t silence[b];
-                       memset (silence, 0, b);
-                       process_audio (silence, b);
+                       if (_opt.video_sync) {
+                               out_with_sync ();
+                       } else {
+                               filter_and_emit_video (_frame);
+                       }
                }
-               
-               avcodec_get_frame_defaults (_frame);
-               
+
+       } else if (ffa && _packet.stream_index == ffa->id() && _opt.decode_audio) {
+
                int frame_finished;
                if (avcodec_decode_audio4 (_audio_codec_context, _frame, &frame_finished, &_packet) >= 0 && frame_finished) {
-                       int const data_size = av_samples_get_buffer_size (
-                               0, _audio_codec_context->channels, _frame->nb_samples, audio_sample_format (), 1
-                               );
+
+                       /* Where we are in the source, in seconds */
+                       double const source_pts_seconds = av_q2d (_format_context->streams[_packet.stream_index]->time_base)
+                               * av_frame_get_best_effort_timestamp(_frame);
+
+                       /* We only decode audio if we've had our first video packet through, and if it
+                          was before this packet.  Until then audio is thrown away.
+                       */
+                               
+                       if (_first_video && _first_video.get() <= source_pts_seconds) {
+
+                               if (!_first_audio) {
+                                       _first_audio = source_pts_seconds;
+                                       
+                                       /* This is our first audio frame, and if we've arrived here we must have had our
+                                          first video frame.  Push some silence to make up any gap between our first
+                                          video frame and our first audio.
+                                       */
                        
-                       assert (_audio_codec_context->channels == _film->audio_channels());
-                       process_audio (_frame->data[0], data_size);
+                                       /* frames of silence that we must push */
+                                       int const s = rint ((_first_audio.get() - _first_video.get()) * ffa->sample_rate ());
+                                       
+                                       _film->log()->log (
+                                               String::compose (
+                                                       N_("First video at %1, first audio at %2, pushing %3 audio frames of silence for %4 channels (%5 bytes per sample)"),
+                                                       _first_video.get(), _first_audio.get(), s, ffa->channels(), bytes_per_audio_sample()
+                                                       )
+                                               );
+                                       
+                                       if (s) {
+                                               shared_ptr<AudioBuffers> audio (new AudioBuffers (ffa->channels(), s));
+                                               audio->make_silent ();
+                                               Audio (audio);
+                                       }
+                               }
+
+                               int const data_size = av_samples_get_buffer_size (
+                                       0, _audio_codec_context->channels, _frame->nb_samples, audio_sample_format (), 1
+                                       );
+                               
+                               assert (_audio_codec_context->channels == _film->audio_channels());
+                               Audio (deinterleave_audio (_frame->data, data_size));
+                       }
                }
                        
-       } else if (_subtitle_stream >= 0 && _packet.stream_index == _subtitle_stream && _opt->decode_subtitles && _first_video) {
+       } else if (_subtitle_stream && _packet.stream_index == _subtitle_stream->id() && _opt.decode_subtitles && _first_video) {
 
                int got_subtitle;
                AVSubtitle sub;
@@ -321,9 +335,14 @@ FFmpegDecoder::do_pass ()
                           indicate that the previous subtitle should stop.
                        */
                        if (sub.num_rects > 0) {
-                               process_subtitle (shared_ptr<TimedSubtitle> (new TimedSubtitle (sub, _first_video.get())));
+                               shared_ptr<TimedSubtitle> ts;
+                               try {
+                                       emit_subtitle (shared_ptr<TimedSubtitle> (new TimedSubtitle (sub)));
+                               } catch (...) {
+                                       /* some problem with the subtitle; we probably didn't understand it */
+                               }
                        } else {
-                               process_subtitle (shared_ptr<TimedSubtitle> ());
+                               emit_subtitle (shared_ptr<TimedSubtitle> ());
                        }
                        avsubtitle_free (&sub);
                }
@@ -333,36 +352,115 @@ FFmpegDecoder::do_pass ()
        return false;
 }
 
-float
-FFmpegDecoder::frames_per_second () const
+/** @param data pointer to array of pointers to buffers.
+ *  Only the first buffer will be used for non-planar data, otherwise there will be one per channel.
+ */
+shared_ptr<AudioBuffers>
+FFmpegDecoder::deinterleave_audio (uint8_t** data, int size)
 {
-       AVStream* s = _format_context->streams[_video_stream];
+       assert (_film->audio_channels());
+       assert (bytes_per_audio_sample());
 
-       if (s->avg_frame_rate.num && s->avg_frame_rate.den) {
-               return av_q2d (s->avg_frame_rate);
+       shared_ptr<FFmpegAudioStream> ffa = dynamic_pointer_cast<FFmpegAudioStream> (_audio_stream);
+       assert (ffa);
+       
+       /* Deinterleave and convert to float */
+
+       assert ((size % (bytes_per_audio_sample() * ffa->channels())) == 0);
+
+       int const total_samples = size / bytes_per_audio_sample();
+       int const frames = total_samples / _film->audio_channels();
+       shared_ptr<AudioBuffers> audio (new AudioBuffers (ffa->channels(), frames));
+
+       switch (audio_sample_format()) {
+       case AV_SAMPLE_FMT_S16:
+       {
+               int16_t* p = reinterpret_cast<int16_t *> (data[0]);
+               int sample = 0;
+               int channel = 0;
+               for (int i = 0; i < total_samples; ++i) {
+                       audio->data(channel)[sample] = float(*p++) / (1 << 15);
+
+                       ++channel;
+                       if (channel == _film->audio_channels()) {
+                               channel = 0;
+                               ++sample;
+                       }
+               }
        }
+       break;
+
+       case AV_SAMPLE_FMT_S16P:
+       {
+               int16_t** p = reinterpret_cast<int16_t **> (data);
+               for (int i = 0; i < _film->audio_channels(); ++i) {
+                       for (int j = 0; j < frames; ++j) {
+                               audio->data(i)[j] = static_cast<float>(p[i][j]) / (1 << 15);
+                       }
+               }
+       }
+       break;
+       
+       case AV_SAMPLE_FMT_S32:
+       {
+               int32_t* p = reinterpret_cast<int32_t *> (data[0]);
+               int sample = 0;
+               int channel = 0;
+               for (int i = 0; i < total_samples; ++i) {
+                       audio->data(channel)[sample] = static_cast<float>(*p++) / (1 << 31);
+
+                       ++channel;
+                       if (channel == _film->audio_channels()) {
+                               channel = 0;
+                               ++sample;
+                       }
+               }
+       }
+       break;
+
+       case AV_SAMPLE_FMT_FLT:
+       {
+               float* p = reinterpret_cast<float*> (data[0]);
+               int sample = 0;
+               int channel = 0;
+               for (int i = 0; i < total_samples; ++i) {
+                       audio->data(channel)[sample] = *p++;
+
+                       ++channel;
+                       if (channel == _film->audio_channels()) {
+                               channel = 0;
+                               ++sample;
+                       }
+               }
+       }
+       break;
+               
+       case AV_SAMPLE_FMT_FLTP:
+       {
+               float** p = reinterpret_cast<float**> (data);
+               for (int i = 0; i < _film->audio_channels(); ++i) {
+                       memcpy (audio->data(i), p[i], frames * sizeof(float));
+               }
+       }
+       break;
 
-       return av_q2d (s->r_frame_rate);
-}
-
-int
-FFmpegDecoder::audio_channels () const
-{
-       if (_audio_codec_context == 0) {
-               return 0;
+       default:
+               throw DecodeError (String::compose (_("Unrecognised audio sample format (%1)"), static_cast<int> (audio_sample_format())));
        }
 
-       return _audio_codec_context->channels;
+       return audio;
 }
 
-int
-FFmpegDecoder::audio_sample_rate () const
+float
+FFmpegDecoder::frames_per_second () const
 {
-       if (_audio_codec_context == 0) {
-               return 0;
+       AVStream* s = _format_context->streams[_video_stream];
+
+       if (s->avg_frame_rate.num && s->avg_frame_rate.den) {
+               return av_q2d (s->avg_frame_rate);
        }
-       
-       return _audio_codec_context->sample_rate;
+
+       return av_q2d (s->r_frame_rate);
 }
 
 AVSampleFormat
@@ -375,20 +473,10 @@ FFmpegDecoder::audio_sample_format () const
        return _audio_codec_context->sample_fmt;
 }
 
-int64_t
-FFmpegDecoder::audio_channel_layout () const
-{
-       if (_audio_codec_context == 0) {
-               return 0;
-       }
-       
-       return _audio_codec_context->channel_layout;
-}
-
-Size
+libdcp::Size
 FFmpegDecoder::native_size () const
 {
-       return Size (_video_codec_context->width, _video_codec_context->height);
+       return libdcp::Size (_video_codec_context->width, _video_codec_context->height);
 }
 
 PixelFormat
@@ -421,46 +509,236 @@ FFmpegDecoder::sample_aspect_ratio_denominator () const
        return _video_codec_context->sample_aspect_ratio.den;
 }
 
+string
+FFmpegDecoder::stream_name (AVStream* s) const
+{
+       stringstream n;
+       
+       AVDictionaryEntry const * lang = av_dict_get (s->metadata, N_("language"), 0, 0);
+       if (lang) {
+               n << lang->value;
+       }
+       
+       AVDictionaryEntry const * title = av_dict_get (s->metadata, N_("title"), 0, 0);
+       if (title) {
+               if (!n.str().empty()) {
+                       n << N_(" ");
+               }
+               n << title->value;
+       }
+
+       if (n.str().empty()) {
+               n << N_("unknown");
+       }
+
+       return n.str ();
+}
+
+int
+FFmpegDecoder::bytes_per_audio_sample () const
+{
+       return av_get_bytes_per_sample (audio_sample_format ());
+}
+
+void
+FFmpegDecoder::set_audio_stream (shared_ptr<AudioStream> s)
+{
+       AudioDecoder::set_audio_stream (s);
+       setup_audio ();
+}
+
+void
+FFmpegDecoder::set_subtitle_stream (shared_ptr<SubtitleStream> s)
+{
+       VideoDecoder::set_subtitle_stream (s);
+       setup_subtitle ();
+       OutputChanged ();
+}
+
+void
+FFmpegDecoder::filter_and_emit_video (AVFrame* frame)
+{
+       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 ()) {
+               graph.reset (new FilterGraph (_film, this, 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);
+
+       for (list<shared_ptr<Image> >::iterator i = images.begin(); i != images.end(); ++i) {
+               emit_video (*i, frame_time ());
+       }
+}
+
+bool
+FFmpegDecoder::seek (double p)
+{
+       return do_seek (p, false);
+}
+
 bool
-FFmpegDecoder::has_subtitles () const
+FFmpegDecoder::seek_to_last ()
 {
-       return (_subtitle_stream != -1);
+       /* This AVSEEK_FLAG_BACKWARD in do_seek is a bit of a hack; without it, if we ask for a seek to the same place as last time
+          (used when we change decoder parameters and want to re-fetch the frame) we end up going forwards rather than
+          staying in the same place.
+       */
+       return do_seek (last_source_time(), true);
 }
 
-vector<AudioStream>
-FFmpegDecoder::audio_streams () const
+bool
+FFmpegDecoder::do_seek (double p, bool backwards)
 {
-       return _audio_streams;
+       int64_t const vt = p / av_q2d (_format_context->streams[_video_stream]->time_base);
+
+       int const r = av_seek_frame (_format_context, _video_stream, vt, backwards ? AVSEEK_FLAG_BACKWARD : 0);
+       
+       avcodec_flush_buffers (_video_codec_context);
+       if (_subtitle_codec_context) {
+               avcodec_flush_buffers (_subtitle_codec_context);
+       }
+       
+       return r < 0;
 }
 
-vector<SubtitleStream>
-FFmpegDecoder::subtitle_streams () const
+shared_ptr<FFmpegAudioStream>
+FFmpegAudioStream::create (string t, optional<int> v)
 {
-       return _subtitle_streams;
+       if (!v) {
+               /* version < 1; no type in the string, and there's only FFmpeg streams anyway */
+               return shared_ptr<FFmpegAudioStream> (new FFmpegAudioStream (t, v));
+       }
+
+       stringstream s (t);
+       string type;
+       s >> type;
+       if (type != N_("ffmpeg")) {
+               return shared_ptr<FFmpegAudioStream> ();
+       }
+
+       return shared_ptr<FFmpegAudioStream> (new FFmpegAudioStream (t, v));
+}
+
+FFmpegAudioStream::FFmpegAudioStream (string t, optional<int> version)
+{
+       stringstream n (t);
+       
+       int name_index = 4;
+       if (!version) {
+               name_index = 2;
+               int channels;
+               n >> _id >> channels;
+               _channel_layout = av_get_default_channel_layout (channels);
+               _sample_rate = 0;
+       } else {
+               string type;
+               /* Current (marked version 1) */
+               n >> type >> _id >> _sample_rate >> _channel_layout;
+               assert (type == N_("ffmpeg"));
+       }
+
+       for (int i = 0; i < name_index; ++i) {
+               size_t const s = t.find (' ');
+               if (s != string::npos) {
+                       t = t.substr (s + 1);
+               }
+       }
+
+       _name = t;
 }
 
 string
-FFmpegDecoder::stream_name (AVStream* s) const
+FFmpegAudioStream::to_string () const
 {
-       stringstream n;
+       return String::compose (N_("ffmpeg %1 %2 %3 %4"), _id, _sample_rate, _channel_layout, _name);
+}
+
+void
+FFmpegDecoder::out_with_sync ()
+{
+       /* Where we are in the output, in seconds */
+       double const out_pts_seconds = video_frame() / frames_per_second();
        
-       AVDictionaryEntry const * lang = av_dict_get (s->metadata, "language", 0, 0);
-       if (lang) {
-               n << lang->value;
+       /* Where we are in the source, in seconds */
+       double const source_pts_seconds = av_q2d (_format_context->streams[_packet.stream_index]->time_base)
+               * av_frame_get_best_effort_timestamp(_frame);
+       
+       _film->log()->log (
+               String::compose (N_("Source video frame ready; source at %1, output at %2"), source_pts_seconds, out_pts_seconds),
+               Log::VERBOSE
+               );
+       
+       if (!_first_video) {
+               _first_video = source_pts_seconds;
        }
        
-       AVDictionaryEntry const * title = av_dict_get (s->metadata, "title", 0, 0);
-       if (title) {
-               if (!n.str().empty()) {
-                       n << " ";
+       /* Difference between where we are and where we should be */
+       double const delta = source_pts_seconds - _first_video.get() - out_pts_seconds;
+       double const one_frame = 1 / frames_per_second();
+       
+       /* Insert frames if required to get out_pts_seconds up to pts_seconds */
+       if (delta > one_frame) {
+               int const extra = rint (delta / one_frame);
+               for (int i = 0; i < extra; ++i) {
+                       repeat_last_video ();
+                       _film->log()->log (
+                               String::compose (
+                                       N_("Extra video frame inserted at %1s; source frame %2, source PTS %3 (at %4 fps)"),
+                                       out_pts_seconds, video_frame(), source_pts_seconds, frames_per_second()
+                                       )
+                               );
                }
-               n << title->value;
        }
+       
+       if (delta > -one_frame) {
+               /* Process this frame */
+               filter_and_emit_video (_frame);
+       } else {
+               /* Otherwise we are omitting a frame to keep things right */
+               _film->log()->log (String::compose (N_("Frame removed at %1s"), out_pts_seconds));
+       }
+}
 
-       if (n.str().empty()) {
-               n << "unknown";
+void
+FFmpegDecoder::film_changed (Film::Property p)
+{
+       switch (p) {
+       case Film::CROP:
+       case Film::FILTERS:
+       {
+               boost::mutex::scoped_lock lm (_filter_graphs_mutex);
+               _filter_graphs.clear ();
        }
+       OutputChanged ();
+       break;
 
-       return n.str ();
+       default:
+               break;
+       }
+}
+
+/** @return Length (in video frames) according to our content's header */
+SourceFrame
+FFmpegDecoder::length () const
+{
+       return (double(_format_context->duration) / AV_TIME_BASE) * frames_per_second();
+}
+
+double
+FFmpegDecoder::frame_time () const
+{
+       return av_frame_get_best_effort_timestamp(_frame) * av_q2d (_format_context->streams[_video_stream]->time_base);
 }