Bug 440842

Summary: kdenlive installs incompatible versions (v.7) of melt and libmlt
Product: [KDE Neon] neon Reporter: Denis Nelubin <dnelubin>
Component: Packages User EditionAssignee: Neon Bugs <neon-bugs-null>
Status: RESOLVED WAITINGFORINFO    
Severity: normal CC: jr, neon-bugs-null, sitter
Priority: NOR    
Version First Reported In: unspecified   
Target Milestone: ---   
Platform: Neon   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description Denis Nelubin 2021-08-10 16:22:08 UTC 
SUMMARY
Installation of kdenlive in current KDE neon User Edition 5.22 causes installation of both libmlt6 and libmlt-7-7. However, libmlt-data v.7 are installed. Kdenlive doesn't work with libmlt7 profiles.

STEPS TO REPRODUCE
1. apt update && apt install kdenlive
2. Run Kdenlive
3. The dialog box to define path to MLT profiles appears. The only available profiles are in /usr/share/mlt-7/profiles. Enter this path.
4. In a new Kdenlive project try to add any video clip to the Project Bin.

OBSERVED RESULT
A error "Cannot open ... file" appears. The clip is not added to the bin. Kdenlive cannot work.

EXPECTED RESULT
No need to set up MLT profiles folder on the first Kdenlive start.
Video clips are successfully added to the bin.

SOFTWARE/OS VERSIONS
Operating System: KDE neon 5.22
KDE Plasma Version: 5.22.4
KDE Frameworks Version: 5.84.0
Qt Version: 5.15.3

ADDITIONAL INFORMATION
The problem is caused by wrong dependencies and common usage of libmlt-data package by both libmlt versions.

Package: kdenlive
Version: 4:21.04.3-0xneon+20.04+focal+release+build32
Depends: ... melt, ..., libmlt++3 (>= 6.24.0), libmlt6 (>= 6.24.0), ...
// kdenlive should depend on specific version of melt

Package: melt
Version: 7.0.1-0xneon+20.04+focal+release+build11
Depends: libmlt-data (>= 7.0.1-0xneon+20.04+focal+release+build11), ..., libmlt-7-7 (>= 7.0.1), ...
// this melt version is installed, it's incompatible with kdenlive

Package: melt
Version: 6.24.0-0xneon+20.04+focal+build9
Depends: libmlt-data (>= 6.24.0-0xneon+20.04+focal+build9), ..., libmlt6 (>= 6.24.0), ...
// even if you hold melt version it tries to install the latest libmlt-data

Package: libmlt-data
Version: 7.0.1-0xneon+20.04+focal+release+build11
// it contains /usr/share/mlt-7/ which is incompatible with kdenlive

Package: libmlt-data
Version: 6.24.0-0xneon+20.04+focal+build9
// it contains /usr/share/mlt/ - the correct data

If I hold both melt and libmlt-data versions to 6.24, kdenlive works.

libmlt-7-7 should have it's own libmlt-data.
kdenlive should not install melt v.7.
Comment 1 Carlos De Maine 2025-09-20 09:35:22 UTC 
Thank you for your bug report! 
However this bug report was created/provided previous to 01/01/2023 and also has not received any updates since  before 01/01/2025. 
Unfortunately KDE neon no longer provides updates for anything older than noble 24.04 based edition's.
Please upgrade to KDE neon noble and if you can reproduce the issue after upgrading to an active version, feel free to re-open this bug report.
Thanks for understanding!