Bug 435793 - 100% CPU usage when playing 4K clip that VLC plays at 15% CPU
Summary: 100% CPU usage when playing 4K clip that VLC plays at 15% CPU
Status: CONFIRMED
Alias: None
Product: kdenlive
Classification: Applications
Component: Video Display & Export (show other bugs)
Version: 20.12.3
Platform: Appimage Linux
: NOR normal
Target Milestone: ---
Assignee: Jean-Baptiste Mardelle
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2021-04-16 00:40 UTC by Dan Dascalescu
Modified: 2021-04-23 16:47 UTC (History)
1 user (show)

See Also:
Latest Commit:
Version Fixed In:
fritzibaby: Brainstorm+

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CPU usage (36.00 KB, image/png)
2021-04-16 00:40 UTC, Dan Dascalescu 		Details
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Description Dan Dascalescu 2021-04-16 00:40:33 UTC 
Created attachment 137646 [details]
CPU usage

When I play 4K clips in Kdenlive like this one[1], CPU utilization goes to 100% on all 8 cores. Changing the preview resolution to 270p doesn't help at all.

My laptop is a ThinkPad X1C with 16GB RAM and Mesa Intel UHD Graphics 620.
I’m using KDE Neon 5.21.4 on X11. The Configuration wizard says "no hardware encoders found" and "Using MLT 6.25.0".

VLC plays the same clips at under 15% CPU utilization.

My goal is to scrub rapidly through clips, but dragging the playhead takes ~2 seconds to seek.

[1]: https://drive.google.com/file/d/1WZsD2bXUJvvCMYVKSbuID539y4WVZ4NZ/view?usp=sharing
Comment 1 emohr 2021-04-23 16:47:22 UTC 
Thank you for reporting. Here similar findings https://invent.kde.org/multimedia/kdenlive/-/issues/811 . Memory and CPU using will be checked in the near future.