@@ -260,6 +260,10 @@ static int64_t video_duration_estimate(const DecoderPriv *dp, const AVFrame *fra
const int ts_unreliable = dp->flags & DECODER_FLAG_TS_UNRELIABLE;
const int fr_forced = dp->flags & DECODER_FLAG_FRAMERATE_FORCED;
int64_t codec_duration = 0;
+ // difference between this and last frame's timestamps
+ const int64_t ts_diff =
+ (frame->pts != AV_NOPTS_VALUE && dp->last_frame_pts != AV_NOPTS_VALUE) ?
+ frame->pts - dp->last_frame_pts : -1;
// XXX lavf currently makes up frame durations when they are not provided by
// the container. As there is no way to reliably distinguish real container
@@ -267,8 +271,13 @@ static int64_t video_duration_estimate(const DecoderPriv *dp, const AVFrame *fra
// the container has timestamps. Eventually lavf should stop making up
// durations, then this should be simplified.
+ // frame duration is unreliable (typically guessed by lavf) when it is equal
+ // to 1 and the actual duration of the last frame is more than 2x larger
+ const int duration_unreliable = frame->duration == 1 && ts_diff > 2 * frame->duration;
+
// prefer frame duration for containers with timestamps
- if (frame->duration > 0 && (!ts_unreliable || fr_forced))
+ if (fr_forced ||
+ (frame->duration > 0 && !ts_unreliable && !duration_unreliable))
return frame->duration;
if (dp->dec_ctx->framerate.den && dp->dec_ctx->framerate.num) {
@@ -285,9 +294,8 @@ static int64_t video_duration_estimate(const DecoderPriv *dp, const AVFrame *fra
// when timestamps are available, repeat last frame's actual duration
// (i.e. pts difference between this and last frame)
- if (frame->pts != AV_NOPTS_VALUE && dp->last_frame_pts != AV_NOPTS_VALUE &&
- frame->pts > dp->last_frame_pts)
- return frame->pts - dp->last_frame_pts;
+ if (ts_diff > 0)
+ return ts_diff;
// try frame/codec duration
if (frame->duration > 0)