Playback issue with libVLC (in Jellyfin). I want to help the devs solve it

[Perseverant]

Hey folks,
First post, and I'm technically savvy, but I'm totally ignorant about the inner workings of libVLC.

I have a rather obscure issue I'm hoping to coordinate with the devs in resolving. There is editing software out there called Avidemux that allows you to losslessly cut encoded video on I-frames. So, as a hypothetical, you could chop a video into three parts, then combine parts one and three in order to losslessly remove the second part.

With VLC on PC, I can edit x264/x265 video in this manner, play the video, and everything seamlessly plays with no indication whatsoever that there has been an edit.
With libVLC (in Jellyfin), there is an odd bug with the video. When the video hits the lossless cut point, it will kind of freeze/glitch out, then resumes playing as normal. It's very jarring and takes you out of the film.

I was wondering if I can help the devs solve this problem so that libVLC can play these sorts of clips seamlessly like the PC client does. Is there any information I can provide, or perhaps even file examples, where I could help you examine/resolve this issue?

[Rémi Denis-Courmont]

Are you sure this is a LibVLC problem in the first place? If you don't mess with the output settings and run on the same hardware and OS, VLC and LibVLC should decode exactly identically.

[Perseverant]

I'm not sure! If I provided you a short example clip, would you be willing to test its playback to rule out libVLC as the source of the problem? If it's not reproduceable on your end, then I could take that back to the Jellyfin devs and start digging into what's going on with the implementation of libVLC in their product.