Bug 494097

Summary: Exported h264_nvenc and hevc_nvenc video is a little bit desynced when playing with Windows native codecs (H264 and Microsoft HEVC Video Extension)
Product: [Applications] kdenlive Reporter: Darko <prezimej>
Component: Rendering & ExportAssignee: Jean-Baptiste Mardelle <jb>
Status: RESOLVED NOT A BUG    
Severity: normal    
Priority: NOR    
Version First Reported In: unspecified   
Target Milestone: ---   
Platform: Other   
OS: Microsoft Windows   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description Darko 2024-10-04 09:29:46 UTC 
Exported h264_nvenc and hevc_nvenc video when played with Windows codecs (WMP, Movies...) shows a video that is just a little bit late behind sound (desynced), I could say even that it is hard to notice but it is visible. Same video works perfect with VLC or K-Lite Codec Pack or when imported in any other video editor just with Windows h264 and with hevc video extension plays desynced as I explained. On the other hand video editor Shotcut render hevc_nvenc that plays normaly with Windows codecs and video players and it is based on MLT and ffmpeg just as Kdenlive so I guess that Kdenlive developers could fix this so that exported hevc_nvenc and h264_nvenc plays normaly (synced) with Windows mp4 codec and HEVC video extension trough WMP or Movies. I tried to change audio codecs and bitrate and almost all settings available but I could not make it work just noticed that video is a little closer to sound when I m using just libx264 or libx265 without nvenc acceleration but it is much slower rendering. I need just hevc_nvenc to export video in sync with Microsoft HEVC video extension just for better compatibility with others, it would not be a problem for me becose I can always use VLC  or some other player and open source codecs to watch it. h264_nvenc is not a problem becose I use it just for sending to Youtube and it's servers render normaly sent video exported with h264_nvenc and Kdenlive
Comment 1 Darko 2024-10-25 10:34:46 UTC 
I found a solution, it was easy, it is important to enter beside other wanted sethings this 3: Buffer size = 1500KiB; GOP=125 frames and Bframes=0
Then exported hevc and h264 file is playing exactly synced audio/video with Microsoft HEVC video extension and Windows native mp4 codec.
(The problem was visible mainly when you are watching when someone is speaking, of course)
It’s not even a bug, just settings tweak.
Hope this helps someone.
Bye
Comment 2 Darko 2024-10-25 10:35:32 UTC 
I found a solution, it was easy, it is important to enter beside other wanted sethings this 3: Buffer size = 1500KiB; GOP=125 frames and Bframes=0
Then exported hevc and h264 file is playing exactly synced audio/video with Microsoft HEVC video extension and Windows native mp4 codec.
(The problem was visible mainly when you are watching when someone is speaking, of course)
It’s not even a bug, just settings tweak.
Hope this helps someone.
Bye