Bug 512264 - Wave Effect does not affect alpha channel
Summary: Wave Effect does not affect alpha channel
Status: CONFIRMED
Alias: None
Product: kdenlive
Classification: Applications
Component: Video Effects & Transitions (other bugs)
Version First Reported In: 25.08.3
Platform: Other Other
: NOR normal
Target Milestone: ---
Assignee: Jean-Baptiste Mardelle
URL:
Keywords: triaged
Depends on:
Blocks:
 
Reported: 2025-11-17 20:48 UTC by toni.k.aittoniemi
Modified: 2025-11-19 21:01 UTC (History)
1 user (show)

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


Attachments
Showing black where alpha channel and wave are in different phases (222.54 KB, image/png)
2025-11-17 20:48 UTC, toni.k.aittoniemi
Details

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Description toni.k.aittoniemi 2025-11-17 20:48:26 UTC
Created attachment 186898 [details]
Showing black where alpha channel and wave are in different phases

SUMMARY

Wave effect when applied to image or video with alpha channel, only affects the color channels and leaves the alpha channel in place.

STEPS TO REPRODUCE
1. Import two images, one with alpha channel information
2. Place a solid image on V1, Alpha image on V2
3. Add Wave filter on V2

OBSERVED RESULT

Wave filter ignores the alpha channel information, only applying to color information

EXPECTED RESULT

Alpha channel moves with the color information, not leaving black areas around edges close to borders of alpha mask

SOFTWARE/OS VERSIONS
macOS:  Ventura 13.7.5

ADDITIONAL INFORMATION

Would be nice for Wave Effect to have separate controls for wavelength and amplitude
Comment 1 Bernd 2025-11-19 21:01:11 UTC
I can confirm the behavior of the Wave effect.

The areas "left" by creating the wave is shown as black not as transparent