HEVC 8-bit 4:4:4 Footage is Very Hard to Playback in Premiere Pro.....Sometimes?

[Eccentric Locust]

I use OBS Studio to record a lot of footage for filmmaking and content creation purposes. One of the methods I use for recording are these settings:

Resolution: UHD 4K (3840x2160)

Frame Rate: 24.00fps

Codec: HEVC

Color Format: I444

Color Space: Rec. 709

Color Range: Limited

File Container: MOV (or MP4 sometimes)

Bitrate Control: CQP (Level 15-25)

These settings allow for me to record 8-bit lossless color in 4:4:4. The MOV container gives me lossless PCM audio.

When I was using these settings, I had no problem editing them in Premiere Pro. However once in a while, my footage becomes extremely hard (if not impossible) playback in Premiere; even without any effects applied. Playback would freeze up on a single frame and not move.

I would have to transcode to ProRes or use ProRes proxies in order to play them back properly.

Yet every so often, the problem randomly goes away and I can play them back decently again. This has been happening in the 2023 and the current 2024 version of Premiere Pro. To be fair, I haven't tried it with v23.6.2 yet. However, replicating it will take a while to do because it happens very randomly.

For some context, here are a few specs from my PC setup:

CPU: Ryzen 9 7950x 16-Core, 32-Thread

GPU: NVIDIA RTX 4090

RAM: 128GB of DDR5

Boot Drive: 2TB Sabrent Rocket Plus M.2 NVME SSD

Working Storage: 8TB Samsung QVO SATA III SSD

I understand that HEVC is a Long GOP codec so it takes more processing power to decode and playback. However, I feel with a system like this that choppy playback shouldn't happen that often or really be this bad. I initally thought it was a media decoder issue with Premiere, but now I'm not really sure anymore. Maybe Premiere Pro has playback issues with media encoded using the FFmpeg encoder in OBS?

I am wondering if anyone else has ever ran into this issue? If so, what have you guys done to solve it?

For me, it's mainly been transcoding to ProRes or ProRes proxies. However, I'm trying to avoid using up storage doing that so I'm looking for a more direct solution.

[Kevin-Monahan]

Hi @Eccentric Locust,

Thanks for the message. Sorry for the performance issues. Only certain systems can handle such footage without issues. AMD CPUs are not optimal for Long GOP footage workflows.

You might want to transcode to a pro editing codec, like ProRes considering your system (or create proxies). If that is not an option, if you swap out your CPU with one of the newer Intel CPUs with Quick Sync, you might have a better experience.

Furthermore, footage coming from OBS is almost always problematic since it usually records using a variable frame rate. If you are concerned about transcoding to a pro editing codec because of file size, you can also try transcoding back to H.264 with a constant frame rate. That might work better. Trancode using Media Encoder. If Media Encoder does not handle the conversion, download FFMPEG-based freeware Shutter Encoder. Either that, or Handbrake can transcode VFR footage.

I hope the advice helps.

Thanks,
Kevin

[Eccentric Locust]

Thanks for reaching back! Really appreciate the insight. So far, it does sound like the ProRes Proxy workflow is the best workaround for now.

Looking more into it, it sounds like Intel's Quick Sync video processor is more compatible with Premiere Pro than AMD's Video Core Next (VCN) processor.

It's interesting really 'cause I have these settings enabled in the Preferences for Premiere Pro to use my GPU, the RTX 4090, to decode H.264 and HEVC codecs (unless hardware accelerated really meant the CPU).

I also have my video previews set to use ProRes as well. Not sure how much of a difference it makes for playback in the timeline, but I still set it to ProRes HQ or LT in case I need to use them to speed up my exports.

My OBS recordings are typically always using a constant frame rate, like 24fps, 29.97, 60fps, etc. Unless OBS is recording constant frame rates using a VFR method? Here's a screenshot of how my frame rate settings tend to look:

Maybe Premiere Pro doesn't like 24.00fps and prefers 23.976fps instead? Not entirely sure, really.

Overall, it's been a pretty wonky thing to run into. I guess if anything, it'd be nice for either Adobe to further increase support for AMD's Video Core Next or for AMD to further improve Video Core Next's ability to decode H.264 and HEVC codecs.

Again, thanks for responding!

[Michael Grenadier]

use media info to determine if your source material is constant or variable frame rate.  AFAIK, Premiere does not display this information.

https://mediaarea.net/en/MediaInfo/Download

Converting to a constant frame rate is important BEFORE creating proxies...

[Eccentric Locust]

I gotcha. Thank you for the heads up!

I got to try out MediaInfo and imported a few clips that have given me some trouble in my Premiere timelines (but again, the issue sometimes randomly goes away, heh).

Apparently, all of the clips I've tried all say that they were recorded using Constant Frame Rate (CFR).

1. HEVC, 8-bit 4:4:4, 24fps, AAC Audio, MP4

2. HEVC, 8-bit 4:2:0, 24fps, PCM Audio, MOV

3. HEVC, 8-bit 4:4:4, 30fps, AAC Audio, MOV (Color Range was incorrectly set to Full but that shouldn't matter.)

The clips I've tried were all recorded using HEVC, though a couple clips were either 4:4:4 or 4:2:0 chroma subsampling, as well as either in the MOV or MP4 container. They were all recorded using CQP, which explains the "Overall bit rate mode" being Variable.

I don't believe I've tried it with H.264 yet (though, I'm a little concerned with image quality if I do but a good CQP Level in Bitrate Control in OBS Studio should help).

Not entirely sure what could cause the issue if all clips were in CFR. Hopefully, there's a way to find the issue!

[Eccentric Locust]

Alrighties! After some research, I think I may have found the answer to my issue and I've narrowed it down to three factors:

1.  Adobe
2.  AMD
3.  Microsoft

1. Adobe

The reason I believe this is partly an Adobe issue is that after some research from Puget Systems, I noticed that Adobe Premiere Pro lacks hardware decoding support for a lot of flavors of both H.264 and HEVC.

Here are a couple screenshots below with links to the articles. They come from 2022 so they are pretty recent.

https://www.pugetsystems.com/labs/articles/what-h-264-and-h-265-hardware-decoding-is-supported-in-pr...

https://www.pugetsystems.com/labs/articles/what-h-264-and-h-265-hardware-decoding-is-supported-in-da...

Compared to DaVinci Resolve, Resolve has the same amount of support for H.264, but has more support for HEVC footage than Premiere Pro. I may put in a feature request later for more support as I feel this would greatly benefit editors working with lots of different kinds of footage.

Keep in mind that I'm running an RTX 4090 and so it should able to handle all of these different flavors of codecs using NVIDIA's NVDEC for video decoding, according to this chart from Wikipedia.

https://en.wikipedia.org/wiki/Nvidia_NVDEC

If Premiere doesn't support hardware decoding for the footage I'm recording, then it's most likely sending that task to my CPU instead of my RTX 4090.

You might notice on the right side of these charts that Intel Quick Sync is mentioned and it supports hardware decoding for not just both H.264 and HEVC, but ALL of the different flavors of HEVC. I'm running a Ryzen 9 7950x, an AMD CPU. This brings me to my next point:

2. AMD

The reason I believe AMD is also a part of this issue is that, while Intel CPUs implement their Quick Sync hardware core for decoding and encoding video, AMD CPUs don't have a hardware core for video encoding and decoding.

As Kevin Monahan mentioned in the pinned reply to this post, AMD CPUs are not optimal for Long GOP workflows; most likely because they lack AMD's Video Core Next hardware core that AMD puts in their GPUs.

If AMD were to put Video Core Next into their CPUs, then perhaps video decoding and playback performance would be much better.

However...

3. Microsoft

In my last post, I shared screenshots for the pieces of HEVC footage that have caused me some trouble with playback. One of those clips was in 4:2:0 instead of 4:4:4. I was able to play that clip on my PC, using Microsoft's HEVC extension from the Microsoft Store.

However when the playback issues happened, I tried opening the clip on my PC in File Explorer and for some reason it wouldn't play anymore and gave me an error.

Once the issue went away in Premiere, I went back into my clip in File Explorer and was able to play it back again.

This was one of the strangest things I've ran into in my entire editing career. My only real conclusion I can get out of this is that maybe Microsoft's HEVC extension basically just sucks? Maybe it was a bug of some sort on Microsoft's end, but I would love to know if maybe there is some connection and possibily a solution.

Conclusion

Overall, that has been my journey with this issue so far. I'm not sure if I may be onto something. But regardless, I do hope Adobe can enable more hardware decoding support for more flavors of both H.264 and HEVC.

In the meantime, I'll probably either continue to use ProRes proxies or record in a different codec in OBS that's more editor-friendly in Premiere for now.

Thank you to everyone that pitched in! Feel free to let me know if there is anything that may shed some more light on this!

[RjL190365]

Here's why:

Your system never had VCN to begin with! Only a discrete AMD Radeon GPU would have supported it in the case of your system - but you have an Nvidia GPU instead of an AMD GPU. As such, you would be using NVDEC for hardware decoding. And although recent Nvidia GPUs technically support hardware decoding of 4:4:4 HEVC video, Adobe had restricted its implementation of NVDEC to 4:2:0. As a result, 4:4:4 material would be forced entirely onto the CPU - and software only, at that.

Oh, by the way, AMD supports only 4:2:0 in its VCN no matter what.