| Summary: | Render Preset for AV1 export using svt-av1 encoder. | ||
|---|---|---|---|
| Product: | [Applications] kdenlive | Reporter: | Richard Ash <richardash1981> |
| Component: | Rendering & Export | Assignee: | Jean-Baptiste Mardelle <jb> |
| Status: | RESOLVED FIXED | ||
| Severity: | normal | ||
| Priority: | NOR | ||
| Version First Reported In: | 25.04.3 | ||
| Target Milestone: | --- | ||
| Platform: | Other | ||
| OS: | All | ||
| See Also: |
https://bugs.kde.org/show_bug.cgi?id=492708 https://bugs.kde.org/show_bug.cgi?id=507333 |
||
| Latest Commit: | Version Fixed In: | ||
| Sentry Crash Report: | |||
| Attachments: | Proposed SVT-AV1 render preset | ||
|
Description
Richard Ash
2025-07-26 19:15:39 UTC
Created attachment 183544 [details]
Proposed SVT-AV1 render preset
Render preset for SVT-AV1. The preset works fine if added as-is, but gets broken if the "Edit" button the Kdenlive GUI is clicked, because some of the changes needed to get CRF adjustment working are reverted.
The changes I had to make by editing the XML were:
- in the "args" attribute, replace `qscale=%quality` with `crf=%quality`
- add to the profile the XML attribute `qualities="1,63"`
Both of these are lost if the "Edit" button the Kdenlive GUI is clicked (the attribute `qualities="1,63"` is lost even if the attribute `manual="1"` is set).
Git commit 1ae508779d53ced51629851c197712de7b870986 by Jean-Baptiste Mardelle. Committed on 26/07/2025 at 21:23. Pushed by mardelle into branch 'release/25.08'. Add quality and speed control to svtav1 preset M +2 -1 data/profiles.xml https://invent.kde.org/multimedia/kdenlive/-/commit/1ae508779d53ced51629851c197712de7b870986 Git commit f4028c1983f6cb660e1bb399ea28fbcaeb320f28 by Jean-Baptiste Mardelle. Committed on 26/07/2025 at 21:33. Pushed by mardelle into branch 'master'. Add quality and speed control to svtav1 preset M +2 -1 data/profiles.xml https://invent.kde.org/multimedia/kdenlive/-/commit/f4028c1983f6cb660e1bb399ea28fbcaeb320f28 Thank you for moving this forward! I had been looking into the issues with editing the preset in the GUI, and got as far as finding this would need a C++ patch to fix in kdenlive-25.04.2 sources. On a quick look the bug still seems to be there on master branch. Roughly the issue is on https://invent.kde.org/multimedia/kdenlive/-/blob/master/src/dialogs/renderpresetdialog.cpp?ref_type=heads#L442, when a new preset gets created from the dialogue, the scaling of the Quality slider doesn't get copied across to the new object. This matters a lot for SVT-AV1 because the useful CRF values are mostly 25 - 50, a lot of which doesn't fit in the default 1-31 Quality scale (unlike many other codecs). Hopefully I can get a patch sorted for this early next week, although it touches a few different places in the dialogue and the model class. Tested new release 25.08.0 (AppImage) and this is there and works. Bug492708 is also fixed in that release, so I think this can be closed now. (Minor nit that the preset name says "(libre-dav1d)", which is inaccurate because dav1d is decode-only! But that is a different (and much less serious) bug to address. |