Announcing the Transcoder Upgrade forum preview! Plex’s transcoder is a highly customized version of FFMPEG which has been accumulating bugfixes and features since it was forked back in 2012. With such a large number of differences, upgrading from the upstream repository became increasingly more di…

AFAIK it only happens when transcoding to H264. It’s most noticeable on anime for me because that’s typically the only thing that ever needs transcoding on my setup when it needs to burn subtitles, and I have HEVC disabled because it doesn’t play nice with Kindle Fire tablets.

I transcoded to H,264. Again, could no repro from this sample. PS: I will move the bulk of this group of threads to the Discussion thread later today. When we find a producible issue for Chris, we’ll post it here.

Like @Atomatth said here, you should get in contact with @chrisallen . He managed to reproduce and somewhat categorize the issue back in 2023. [image] Transcoder Upgrade Forum Preview Plex Media Server Thanks! man_facepalming Missed that comment. I’ll sync up with @chrisal…

@chris_decker08 saw some other subtitles mentioned here so I thought I would mention. DVB_Teletext subtitles on Australian Live TV completely crashes the whole server when enabled. Unsure if this is player related, transcoder related or both.

@tree2369 can you easily reproduce? If so, can you please enable debug logging , reproduce the issue, then grab your PMS logs and share them here? Also, can you confirm that this is only happening on the Forum Preview build and not the current production/beta channels?

@Atomatth Can definitely get some logs. Though yes this is also a issue that affected the production/beta channels, though only very recently.

@chris_decker08 I’m seeing some issues with media that is UHD DoVI Profile 8 with HDR10 fallback and transcoding down to 720p for remote viewing. Colors are acting weird, almost like it’s not falling back to HDR10 when transcoding. Occurs on iOS and tvOS with both the New and Old Experience apps. I…

This is great news, and I’ll give it a whirl after I return from a business trip. Right now, I’m “downloading” movies to be able to watch them on the plane, and I am using the new Plex app on iOS 18.5. The server is only transcoding one movie at a time, and only using a single thread/core. I have…

@djfriday13 I am classifying this under the category of follow on work as the upgrade is a pre-perquisite but requires additional work on both PMS and the client.

@tree2369 like @Atomatth said, logs will defiantly be helpful here. Its possible that my work on A53 CC subtitles will fix this for you, however since I cannot repo we won’t know until you try :slight_smile:

Transcoder Upgrade Forum Preview

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Transcoder Upgrade Forum Preview

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