Issue with subtitle glyph display

[justmeyep 5]

9 minutes ago, pwhodges said:

I have a lot of AV1 files, and I can't reproduce either of these behaviours...  I guess my machines are more powerful than yours, but can't see any good reason why that would matter.  I suppose there could be a race condition that could be triggered by multiple fast commands on a slow machine, but in that case I'd expect more reports of it.

I suspect it could be linked to the way they are encoded possibly?

Would you be so kind and test one of my affecting files if it isn't too much to see if it is the above or indeed only happening on low end hardware?

5 minutes ago, pwhodges said:

But Emby doesn't extract them on the fly unless you tell it to.  A properly structured file for streaming can be played without the subs being extracted.  In my tests for the hangs you get, I jumped back and forth between the ends of a video while playing with subs, and the jumps were instant, with the subs appearing instantly as well.

It's only possible to display the subtitles in a web client when they are extracted or burned into the video, correct? In that case for me only the first scenario is possible and the initial extraction of the subtitles takes some time, after that it is pretty much instant. But the first extraction can, depending on the size, take 2-3 minutes in the worst case which isn't very nice. That's why I am providing them externally.

[pwhodges 2012]

I can test a file if you PM me a link.  (It's too late here for me to do that this evening, but I can do it in the morning.)

Yes, you're right about subs in a web browser, and I can see your logic in extracting subs for the situation that you don't have the server power for routinely transcoding.  The extraction may take longer for larger video files (higher bit rates), and from the examples above you are using bigger files than I am.

Paul

Edited June 9, 2023 by pwhodges

[justmeyep 5]

Sent, thank you very much! 

For some reason the transcoded files have the  aforementioned issues. When I tried the original release (HEVC) this didn't happen.

In every other client so far it works in that regard 

[Luke 42078]

On 6/9/2023 at 6:40 PM, pwhodges said:

I can test a file if you PM me a link.  (It's too late here for me to do that this evening, but I can do it in the morning.)

Yes, you're right about subs in a web browser, and I can see your logic in extracting subs for the situation that you don't have the server power for routinely transcoding.  The extraction may take longer for larger video files (higher bit rates), and from the examples above you are using bigger files than I am.

Paul

Did he send you a sample?

[pwhodges 2012]

Yes.  I was leaving them to respond in their thread, but the outcome was the same on my local server and with me connecting to their server:  On my desktop (Intel i5 12G + A380 video card, Win 11) I can play the file (AV1 encoded, with embedded ASS subs on) using Windows Theatre for Desktop  and seek back and forth as fast as I like using different methods, and it keeps playing perfectly.  Using the same files and servers, and Windows Theatre on my old laptop (Intel i5 3G, Win 10), again AV1 + ASS, the very first seek I do causes Theatre to hang with no way to back out; this is repeatable.  The laptop seeks fine with HEVC + ASS files.

I wonder If there is some race condition in the AV1 code in Theatre which only causes a problem with slow processors.

Paul

[justmeyep 5]

On 14/06/2023 at 00:15, pwhodges said:

Yes.  I was leaving them to respond in their thread, but the outcome was the same on my local server and with me connecting to their server:  On my desktop (Intel i5 12G + A380 video card, Win 11) I can play the file (AV1 encoded, with embedded ASS subs on) using Windows Theatre for Desktop  and seek back and forth as fast as I like using different methods, and it keeps playing perfectly.  Using the same files and servers, and Windows Theatre on my old laptop (Intel i5 3G, Win 10), again AV1 + ASS, the very first seek I do causes Theatre to hang with no way to back out; this is repeatable.  The laptop seeks fine with HEVC + ASS files.

I wonder If there is some race condition in the AV1 code in Theatre which only causes a problem with slow processors.

Paul

Sorry, I didn't find the time to respond in a timely manner..

This is correct, it seems to be an issue with the Client and not the server or the files.

I don't think it's an issue with slower processors though - I'm running an AMD Ryzen 7 5800X with a Radeon RX 6700 XT. The 6700 XT *should* also have Hardware AV1-decoding support from what I know.

Thank you for helping me figure out where the problem lies @pwhodges, it would be nice if it were possible to look into it and get it resolved.