Try to fix overrunning subtitles.

2 files changed, 5 insertions, 3 deletions

diff --git a/src/lib/decoder.cc b/src/lib/decoder.cc
index da75decc8..045c1b818 100644
--- a/src/lib/decoder.cc
+++ b/src/lib/decoder.cc
@@ -463,7 +463,7 @@ Decoder::process_subtitle (shared_ptr<TimedSubtitle> s)
 {
 	_timed_subtitle = s;
 	
-	if (_opt->apply_crop) {
+	if (_timed_subtitle && _opt->apply_crop) {
 		Position const p = _timed_subtitle->subtitle()->position ();
 		_timed_subtitle->subtitle()->set_position (Position (p.x - _fs->crop().left, p.y - _fs->crop().top));
 	}
diff --git a/src/lib/ffmpeg_decoder.cc b/src/lib/ffmpeg_decoder.cc
index e954294ec..9891bb55b 100644
--- a/src/lib/ffmpeg_decoder.cc
+++ b/src/lib/ffmpeg_decoder.cc
@@ -309,11 +309,13 @@ FFmpegDecoder::do_pass ()
 		int got_subtitle;
 		AVSubtitle sub;
 		if (avcodec_decode_subtitle2 (_subtitle_codec_context, &sub, &got_subtitle, &_packet) && got_subtitle) {
-			/* I'm not entirely sure why, but sometimes we get an AVSubtitle with
-			   no AVSubtitleRects.
+			/* Sometimes we get an empty AVSubtitle, which is used by some codecs to
+			   indicate that the previous subtitle should stop.
 			*/
 			if (sub.num_rects > 0) {
 				process_subtitle (shared_ptr<TimedSubtitle> (new TimedSubtitle (sub, _first_video.get())));
+			} else {
+				process_subtitle (shared_ptr<TimedSubtitle> ());
 			}
 			avsubtitle_free (&sub);
 		}