I am getting audio stutter when I try to play audio files with my channel when I use a frame rate of 2997 or 5994, the latter of which is required for my application. I tested p2500, p3000 which show up fine on the screen consumer. p2997 and i5994 both crackle on the screen consumer and I have confirmed that i5994 crackles and stutters on the decklink output also. This seems to be a recurring issue where some sort of audio bug effects these frame rates. What build or version do I need to run to avoid this? I am using the latest stable releases (2.4.1 and 2.4.2) Is there a specific build that works better with interlaced signals, or are there settings i can change to make it work better?
I see several bugs being documented over on github for these issues, but no one seems to merge the fixes? Is there a fork that works at these frame rates?
Update: I figured out the temporary solution! 2.3.3 LTS Stable seems to have the appropriate patch applied. This needs documented better…
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I’m pretty sure that nothing has been explicitly changed on this, but non-integer framerates have been neglected for years, there are many open github issues around this
Yeah, I noticed several around this. I was kind of surprised to see the problem again, but 2.3.3 LTS works and 2.4.1 Stable and 2.4.2 Stable have the problem again.
Is this with audio files only? Can you confirm this is an issue with 1080i5994 video files or decklink input?
My testing was done with MP4 video files in 1080p2997 and 1080i5994 channel resolutions and matching files along with some other frame rates. I have not tested audio files or decklink inputs but can add that to the tests soon. Version 2.5 compiled from git master for Linux does not have the audio stutter problem. I have seen stutter on a few files with 2.3.3 LTS, but I need to do additional testing to rule out other system limitations such as hdd bandwidth for those.
Is there a specific audio file format I should test?
I can say very confidently that nothing has changed between 2.4 and 2.5 on how this is handled. Any differing results will be based on luck or a flawed test.
I was doing some testing on this recently on v2.4.0-NRK-RC5. I was using 1080i5994 files on 1080i5994 channels as well as 1080i5994 deckilnk producer. Both producers seemed to work great and play out with correct audio to decklink consumer. What isn’t working is the system audio consumer.
If anyone wants me to test any files on my system, please DM links to me.
BTW, it’s been a while since I’ve worked with CasparCG Server. I totally missed it! Thanks to all that have kept development going over the years!
So I have just looked at my files closer and it appears like I have more variety in frame rates than I thought. One file in particular was 23.976p playing to a 5994i channel and that was showing the same issue I originally reported even with 2.5 master. Transcoding that mp4 file to 5994i fixed the playback issue so it would have been in the frame rate conversion part. I can provide a sample if someone wants to look into fixing that part.