Bug 493347

Summary:	Crop, Scale and Tilt uses CPU
Product:	[Applications] kdenlive	Reporter:	Deniil <entityinarray>
Component:	Video Effects & Transitions	Assignee:	Jean-Baptiste Mardelle <jb>
Status:	RESOLVED UPSTREAM
Severity:	normal	CC:	berndmj
Priority:	NOR
Version First Reported In:	24.08.1
Target Milestone:	---
Platform:	Other
OS:	Other
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Deniil 2024-09-19 08:27:56 UTC

SUMMARY
Crop, Scale and Tilt uses CPU. Using such filter in a project will cause rendering to slow down to 20 frames/s even with NVENC.

STEPS TO REPRODUCE
1. Create a new project
2. Apply Crop, Scale and Tilt to a video
3. Render with NVENC
4. Remove Crop, Scale and Tilt
5. Render again, see major performance difference

OBSERVED RESULT
Crop, Scale and Tilt and all other filters should use GPU

EXPECTED RESULT
Crop, Scale and Tilt bottlenecks rendering

SOFTWARE/OS VERSIONS
Windows: Windows 10 Pro
KDE Plasma Version: 24.08.1
KDE Frameworks Version: 6.5.0
Qt Version: 6.7.2

Comment 1 Bernd 2024-09-19 16:21:07 UTC

Thank you for your report.

Kdenlive uses the MLT framework for effect application, compositing, and all other frame handling. At the current release level of MLT, the use of GPU for these things is only available through the use of the movit library but there are several issues with it and therefore has been switched off for Kdenlive. MLT also hands over the frames to ffmpeg for encoding.

Please get in touch with the MLT team for this topic.