Fix reffing of the AVFrame output by the decoder.

[dcpomatic.git] / src / lib / ffmpeg_decoder.cc

diff --git a/src/lib/ffmpeg_decoder.cc b/src/lib/ffmpeg_decoder.cc
index 2d7092789b849de3110e07ceb7f980d28eb187bf..8e09810cb2cc75c3a6109139e0a0db8427f4eb8e 100644 (file)
--- a/src/lib/ffmpeg_decoder.cc
+++ b/src/lib/ffmpeg_decoder.cc
@@ -453,18 +453,20 @@ 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_(" ");
+
+       if (s->metadata) {
+               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;
                }
-               n << title->value;
        }
 
        if (n.str().empty()) {
@@ -530,7 +532,7 @@ FFmpegDecoder::filter_and_emit_video ()
 bool
 FFmpegDecoder::seek (double p)
 {
-       return do_seek (p, false);
+       return do_seek (p, false, false);
 }
 
 bool
@@ -540,21 +542,57 @@ FFmpegDecoder::seek_to_last ()
           (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);
+       return do_seek (last_source_time(), true, false);
+}
+
+void
+FFmpegDecoder::seek_back ()
+{
+       do_seek (last_source_time() - 2.5 / frames_per_second (), true, true);
+}
+
+void
+FFmpegDecoder::seek_forward ()
+{
+       do_seek (last_source_time() - 0.5 / frames_per_second(), true, true);
 }
 
 bool
-FFmpegDecoder::do_seek (double p, bool backwards)
+FFmpegDecoder::do_seek (double p, bool backwards, bool accurate)
 {
        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);
        }
-       
+
+       if (accurate) {
+               while (1) {
+                       int r = av_read_frame (_format_context, &_packet);
+                       if (r < 0) {
+                               return true;
+                       }
+                       
+                       avcodec_get_frame_defaults (_frame);
+                       
+                       if (_packet.stream_index == _video_stream) {
+                               int finished = 0;
+                               int const r = avcodec_decode_video2 (_video_codec_context, _frame, &finished, &_packet);
+                               if (r >= 0 && finished) {
+                                       int64_t const bet = av_frame_get_best_effort_timestamp (_frame);
+                                       if (bet > vt) {
+                                               break;
+                                       }
+                               }
+                       }
+                       
+                       av_free_packet (&_packet);
+               }
+       }
+               
        return r < 0;
 }