ffmpeg: Check duration for overlap and clip in fps cfr/vfr code

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

1 files changed, 7 insertions, 0 deletions

diff --git a/ffmpeg.c b/ffmpeg.c
index 3b24cf99da..e51e789b03 100644
--- a/ffmpeg.c
+++ b/ffmpeg.c
@@ -904,6 +904,13 @@ static void do_video_out(AVFormatContext *s,
     sync_ipts = next_picture->pts;
     delta0 = sync_ipts - ost->sync_opts;
     delta  = delta0 + duration;
+    if (delta0 < 0 && delta > 0) {
+        double cor = FFMIN(-delta0, duration);
+        av_log(NULL, AV_LOG_WARNING, "Past duration %f too large\n", -delta0);
+        sync_ipts += cor;
+        duration -= cor;
+        delta0 += cor;
+    }
 
     /* by default, we output a single frame */
     nb0_frames = 0;