Bug 514142 - Rendering crashed without reason given -> Median-effect
Summary: Rendering crashed without reason given -> Median-effect
Status: REPORTED
Alias: None
Product: kdenlive
Classification: Applications
Component: Rendering & Export (other bugs)
Version First Reported In: 23.04.3
Platform: Microsoft Windows Microsoft Windows
: NOR crash
Target Milestone: ---
Assignee: Jean-Baptiste Mardelle
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2026-01-04 12:46 UTC by Der Mueller
Modified: 2026-01-19 02:23 UTC (History)
1 user (show)

See Also:
Latest Commit:
Version Fixed/Implemented In:
Sentry Crash Report:


Attachments
Screenshot: kdenlive 25.12.0 Timeline and effects with selected frame rendering fails on. (84.29 KB, image/png)
2026-01-04 12:46 UTC, Der Mueller
Details

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Description Der Mueller 2026-01-04 12:46:06 UTC
Created attachment 188209 [details]
Screenshot: kdenlive 25.12.0 Timeline and effects with selected frame rendering fails on.

SUMMARY
Initial Video is longer. Render always crashes at same position/frame. To show Bug: rendered (tried to) only problemmatic part.

STEPS TO REPRODUCE
1. Render Video with effects

OBSERVED RESULT
Render crashes (after Waiting about 1 Minute to start rendering - due to project size)

EXPECTED RESULT
Rendered Video

OS VERSIONS
Windows 10 Version 22H2 Build 19045.6456
Debugging-information:
Kdenlive: 25.12.0 - rev. 8ed1d6b
MLT: 7.35.0
FFmpeg: 
Package Type: Unknown/Default
Qt: 6.10.1 (built against 6.10.1 x86_64-little_endian-llp64)
Frameworks: 6.20.0
System: Windows 10 Version 22H2
Kernel: winnt 10.0.19045
CPU: x86_64
Windowing System: windows
GPU: 
Movit (GPU): disabled
Track Compositing: qtblend


ADDITIONAL INFORMATION
initially created in 23.x (forgot which version) (newver rendered this version)
-> upgraded to latest (25.12.0) (not rendered)
-> downgrade to 24.02.2
Version change due to a different Bug/Problem with Performance, what turned out to be a issue with the AMD Chipset-driver
24.02.2 - first time render failed.
then Also installed versions: 
23.08.5
25.12.0 (again)
23.04.3
-- All render failed.

(25.12.0) render log: video_1080p_h0x6.mp4.log
```
Started render process: D:/Programme/kdenlive25/bin/melt.exe -loglevel error -progress2 C%3A%2FUsers%2Fusername%2FAppData%2FLocal%2FTemp%2Fkdenlive-xxVswP-1.mlt
60	5	1
61	10	2
62	20	4
Rendering of C:/Users/Der_Mueller/Videos/video_1080p_h0x6.mp4 aborted, resulting video will probably be corrupted.

Frame: 20
```
(23.04.3) Render log.
Same as 25.12.0 but also multiple like:
[mov,mp4,m4a,3gp,3g2,mj2 @ 0000019388950040] st: 0 edit list: 1 Missing key frame while searching for timestamp: 1000 
[mov,mp4,m4a,3gp,3g2,mj2 @ 0000019388950040] st: 0 edit list 1 Cannot find an index entry before timestamp: 1000. 
-- no other msg.

A little testing: (in 23.04.3)
Effect Median is the Problem. The Frame it failes on:
Planes: U
Spatial sigma: 81,870
Median vertical radius 121,740
Median percentile: 0,766

(The second Median effect: Blue/UV - just works)


Info to Attachment:

screenshot of problematic part. (blue part selection)
exact frame where render failes selected.
To mention: there is no key set (keyframe) on the frame the render failes