Greetings,

I am using Mirillis Action! to record game-play footage from Forza Horizon 4. Action offers the option to record using AMD AMF HEVC hardware acceleration, which is great as it produces nice quality and it doesn't impact performance on my system. With that said, I am facing problems when editing the files in kdenlive. To better explain the issue I have uploaded three videos to my own server, the login credentials are action/action.

The three videos are - forza-sample-raw.mp4, which is the recording produced by Action (raw in the sense that it's an unaltered file produced by Action). The recording plays fine, no issues there, this can be seen in the second video, titled screen-recording.mkv. There I used OBS to record my desktop to show what happens when I try and edit forza-sample-raw.mp4 using Kdenlive. The third and last video (test-encode.mp4)is the exported edit from Kdenlive.

Is there any way I could make kdenlive work better with the source files I produce?

Thank you for your help in advance!

Kind regards,

Gyuszi

PS: System specs - AMD Ryzen 7 2700, 16GB, RX 580 4GB, Windows 10 v2004, the videos are on a 1TB Samsung 860 EVO SSD.

Which Kdenlive version do you use? Disable "parallel processing" for rendering.

I am using Kdenlive version 20.04.1. Disabling "parallel processing" for rendering made no difference, the resulting file contains the same kind of glitches.

Could that be similar to this issue: https://bugs.kde.org/show_bug.cgi?id=423574 ? Meaning, does it work before the 2004 update?

The issue you posted looks like a different problem. In my case only parts of the video are grayed out and that's without using any filters or effects, plus the glitches appear in the project preview window as well and not just in the rendered video file.

I think I found the issue. I downloaded your screencast. 1920x1200 is not an official MP4 standard. Set the project settings to 1080p60 and put the video on the timeline without accepting the change of the project setting. Cut it as needed. Render it. My rendered file has no glitches.

Hi Merlimau,

Thank you for your continued help in trying to get to the bottom of this issue I appreciate it.

I tried your suggestion, changed the default profile to 1080p60, when adding the clip I did not accept changing the project setting. Unfortunately, once the clip is added, the grey artifacts appear in the preview window right away when seeking through the clip. Cutting the clip into parts, and rearranging them - so basically doing a quick edit - results in the same artifacts. The resulting render also has the same graphical artifacts. Have you tried editing the sample file I uploaded?

In the meantime I changed the recording settings in Action!, so now I record into AVI without HW acceleration, using their proprietary FICV codec. This works, but the resulting file size is much bigger (this I expected). I really think the problem is with the way HEVC files are handled in Kdenlive.

Another thing I tried just now is transcoding the clip to Lossless Matroska (using Kdenlive), and then working with the resulting file. This did the trick, but the growth in file size makes this unfeasible. The 75MB sample file becomes 3,6GB once transcoded to lossless matroska, which is insane. Especially for a short clip where nothing really happens.

Kind regards,

Gyuszi

Yes I have edited the file uploaded but I'm on Win7.
You can try to change the original file to MKV (i.e. with https://mkvtoolnix.download). Maybe it works better.

Out of curiosity I tried editing forza-sample-raw.mp4 on my notebook running Elementary OS, and the exact same behavior was present there as well. Oh well :S