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
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.