No hardware acceleration for 4k encoding (h.264, h.265)

[defaultlxanzq8djm83]

Hi all,

I am working with 4k footage for the first time (Canon 4k IPB, 29.97 fps), and it won't use hardware acceleration for encoding. I am currently running it through the HEVC (H.265) encoding, match source - high bitrate standard settings, and despite letting me send it to AME with hardware encoding turned on, it won't stay on. Confusingly, I was able to get one video to encode with hardware acceleration with these settings, and I have no idea why.

• AMD Ryzen 7 3700x 8-core, 3600 MHz
• NVidia GeForce RTX 2070 Super (8 GB RAM), is on Adobe's hardware acceleration list
• 64 GB installed RAM, 3200 Mhz DDR4
• Windows up to date, clean install 2 weeks ago
• Version 22 of AME, Premiere (using Red Giant plug-ins, known issue with current versions)
• AME Renderer is showing Mercury Playback Engine GPU Acceleration (CUDA)

I tried an old project to see if something strange was happening with the system because it's a clean Windows install and I added 32 GB of RAM. The footage was FHD 29.97P IPB with the same Red Giant plug in effects, ran through the h.264 high bitrate setting, and it was able to use the video card for acceleration.

I feel like I am missing a critical piece of information for what's going on. I've tried many different export setting configurations, and I cannot get hardware acceleration to work. The one video that did export quickly was after loading up the queue, closing Premiere, saving the AME queue, and restarting it. I went to sleep after I saw it was going fast and using the GPU, so am not sure what happened.

[Kevin-Monahan]

Hello there community member,

Thanks for writing. Sorry that something is off in your hardware encoding. Can you please embed a screenshot of your Export Settings dialog box? That can help diagnose the issue.

Thanks,
Kevin

[defaultlxanzq8djm83]

Sure. This is as the video is sitting in AME's queue. When setting the options in Premiere, Hardware Encoding was an option, and leaving it set didn't result in the "Your system's hardware does not support hardware acceleration for the current settings" pop up box (which happens in AME). I think it was set at Profile Main, Level 5.2 (I think ?). I tried differently level settings, but it 1) didn't change the software/hardware encoding issue, and also changed the image/file size. Yeah, I realize that's probably exactly what the level option does, but I don't know why hardware acceleration will not work here.

I clicked around with bit rates earlier but it didn't seem to buy me hardware acceleration.

[defaultlxanzq8djm83]

Was checking settings in Premiere, so here's the output settings before it's handed over to AME

(And hardware acceleration is turned on in all applicable Premiere preference menus)

[R Neil Haugen]

First, we need to make sure of which 'hardware acceleration' you're talking about. There are two totally different things there.

The first is GPU use in those effects which are GPU accelerated, such as Lumetri and Warp stabilizer. That is contolled by the settings in the Project panel for Mercury Accleration.

And it has nothing whatever to do with the phrase 'software only' in the Export dialog summary section.

The phrase 'software ... ' that appears in the Export dialog summary section only has to do with whether your CPU has the right internal hardware for accelerated H.264/5 encoding. Period.

The setting for H.264/5 encoding use of the CPU's hardware (when and if available) is in the Preferences dialog for Premiere. And actually, Hardware encoding when available is typically faster, but Software encoding of H.264/5 files is typically better quality. And I'm not sure if any AMD CPU can do that, @RjL190365  has the best knowledge on CPU capabilities.

And hardware acceleration is never available for any 2-pass H.264/5 encoding processes.

So ... are you talking about the Summary section of the Export dialog? Or about the use of the GPU for Lumeti, Warp, and other GPU-accelerated effects?

Neil

[defaultlxanzq8djm83]

Hi Neil,

I'm talking about the summary section of the export dialog.

I realize there is a bit of a trade off for software and hardware encoding. I'm okay with that. The thing that has me stumped is my video card being on Adobe's list, having enough RAM and whatnot (could be wrong), and hardware acceleration working for projects not using 4k video.

I saw the part about it not working for 2-pass encodings, possibly from one of your other posts, so was very sure I was going into AME with single-pass selected.

[RjL190365]

Check the video bitrate in your export settings. If that is greater than 50 or 60 Mbps, then you cannot use hardware encoding at all: Either the encoder will automatically switch to software-only encoding, or the encoding bitrate will default to a much lower than selected bitrate (about 16 Mbps instead of the 80 Mbps that you wanted).

[defaultlxanzq8djm83]

Okay, assuming I'm looking in the right place, it's set to VBR 1 pass, target of 7 Mbps, max 10 Mbps in the processing files in AME. The export settings from Premiere were VBR 1 pass, target 7 Mbps

[R Neil Haugen]

To say it again: Premiere does not use the GPU for basic encoding in general, it tends to reserve the GPU to handle the GPU Accelerated Effects (Warp, Lumetri, etc) and size scaling.

Where that occurs in your timeline tge GPU will be used as it is called for.

Where it doesn't, tge GPU will only be used as the CPU may choose to request assistance.

Neil

[defaultlxanzq8djm83]

Right, okay. Can you help me understand why I'm seeing a huge difference in GPU utilization between the 4k and FHD footage, when rendering with identical effects? No warping or scaling, just Red Giant's Colorista.

Right now (with 4k) it's at 7%, but with the FHD it will be well above that.

Also, thank you for your time.

[Andy 1968]

Defualtxzanzq,

Neil is incorrect.

The Nvidia GPUs since the 600 series have Nvenc. Nvenc is for hardware encoding and decoding of H.264/265 while CUDA is for the GPU accelerated effects. That being said not all variations of H.264/265 are supported. 

The video below shows Nvidia's Nvnec in action as well as Intel's Quick Sync in action. You can click on your RTX 2070 Super using Windows Task Manger and see if it is encoding and decoding. I demonstrate this in the video below.