There have been many reports over the years about problems when taking an HLS stream as input to `ffmpeg` where there are timestamp discontinuities present. This is explicitly supported in the HLS spec (EXT-X-DISCONTINUITY) and often used for ad injection.
Various fixes and work-arounds have been proposed over the years, but one step that seems obvious, even if it's not a complete fix, is to mark the HLS input format as supporting discontinuities. This will prevent timestamp fixup logic in ffmpeg.c kicking in that ends up mangling the timestamps unnecessarily. I've tested this out with an example provided by Joe Koberg early last year, and it is sufficient to allow `ffmpeg` to download and mux the stream correctly. Joe had briefly suggested that other situations can still be handled incorrectly, but this seems like a strict improvement. Joe's example: https://s3.amazonaws.com/playon-test-videos/discont_test_new/discont_test.m3u8 --- libavformat/hls.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavformat/hls.c b/libavformat/hls.c index d7f4d5b442..ac151d5ca4 100644 --- a/libavformat/hls.c +++ b/libavformat/hls.c @@ -2326,7 +2326,7 @@ AVInputFormat ff_hls_demuxer = { .long_name = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming"), .priv_class = &hls_class, .priv_data_size = sizeof(HLSContext), - .flags = AVFMT_NOGENSEARCH, + .flags = AVFMT_NOGENSEARCH | AVFMT_TS_DISCONT, .read_probe = hls_probe, .read_header = hls_read_header, .read_packet = hls_read_packet, -- 2.20.1 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
