Bug 442197

Summary: A particular set of ladspa plugins do not work at all
Product: [Applications] kdenlive Reporter: Natalia Portillo <claunia>
Component: Video Effects & TransitionsAssignee: Massimo Stella <maxstar>
Status: CONFIRMED ---    
Severity: normal CC: claunia, julius.kuenzel
Priority: NOR    
Version First Reported In: 21.08.1   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description Natalia Portillo 2021-09-08 22:43:54 UTC 
SUMMARY
A particular set of ladspa plugins do not work at all.
https://lsp-plug.in/

The appear in the list, they're detected in command line output, but they don't work properly. Other LADSPA plugins work perfectly.

STEPS TO REPRODUCE
1. Add a new audio clip
2. Apply an LSP plugin
3. Set the parameters

OBSERVED RESULT
The audio clip is completely muted, the volume meters are 0, and no sound can be heard.

EXPECTED RESULT
The plugin filters the audio properly.

SOFTWARE/OS VERSIONS
ArchLinux rolling
Linux: 5.13.13-arch1-1
KDE Plasma Version: 5.22.5-1
KDE Frameworks Version: 21.08.1-1
Qt Version: 5.15.2+kde+r222-1

ADDITIONAL INFORMATION
SWH LADSPA plugins work properly.
Comment 1 Julius Künzel 2021-09-28 22:36:30 UTC 
Thanks for your report! We are going to check this…