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The rational for this is another issue that plex has exposed. When it is conducting a transcode of video to HLS for streaming, my father noticed artifacts when played on his GoogleTV (NSZ-GT1). He sent me a test file and I reproduced it on my device of the same model. It is important to note that the artifacts were not present when streaming to VLC or QuickTime Player. I copied the command-line that plex used, and conducted all of the following tests using FFmpeg git. Transcode to HLS: artifacts on playback Transcode to TS: playback is fine Cat HLS segments into a single TS: playback is fine Segment single TS file to segments: artifacts on playback Segment single TS file to segments using Apple's HLS segmenter: playback is fine At this point I carefully examined the differences between Apple's HLS segmenter output and FFmpeg's. Among the considerable differences, I noticed that the video PES packets always had a 0 length. So I continued: Transcode to HLS using FFmpeg with 0 length PES packets: playback is fine. Segment single TS to segments with 0 length PES packets: playback is fine. All failures mentioned are only on the GTV since it is the only player on which I could reproduce artifacts. I only tested the GTV, VLC, and QuickTime Player though, so my test case is limited. I do not know if other players exhibit this issue. Since it was useful last time, I have uploaded the test file as hls_pes_packet_length.m4v along with its associated txt file which contains the transcode command-line that was used. Reviewed-by: Kieran Kunhya <kierank@obe.tv> Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
FFmpeg README ------------- 1) Documentation ---------------- * Read the documentation in the doc/ directory in git. You can also view it online at http://ffmpeg.org/documentation.html 2) Licensing ------------ * See the LICENSE file. 3) Build and Install -------------------- * See the INSTALL file.