Fix errors when seeking FFmpeg for some formats.

The comments discuss this in a bit more depth, but basically we see
errors from avcodec_send_packet after seek.  ffplay etc. seem basically
to ignore all errors from avcodec_send_packet, and I can't find a
"proper" fix, so here's a half-way house hack: ignore some errors
after seek.  Nasty.

1 files changed, 3 insertions, 0 deletions

diff --git a/src/lib/ffmpeg_decoder.h b/src/lib/ffmpeg_decoder.h
index fce3fcae9..def824feb 100644
--- a/src/lib/ffmpeg_decoder.h
+++ b/src/lib/ffmpeg_decoder.h
@@ -79,6 +79,9 @@ private:
 	/** true if we have a subtitle which has not had emit_stop called for it yet */
 	bool _have_current_subtitle = false;
 
+	/** number of errors from avcodec_send_packet to ignore */
+	int _errors_to_ignore = 0;
+
 	std::shared_ptr<Image> _black_image;
 
 	std::map<std::shared_ptr<FFmpegAudioStream>, boost::optional<dcpomatic::ContentTime>> _next_time;