FS#57097 - [mlt] Kdenlive video preview uses only one thread

Attached to Project: Arch Linux
Opened by Elias (Bleuzen) - Sunday, 14 January 2018, 18:59 GMT
Last edited by Antonio Rojas (arojas) - Monday, 15 January 2018, 19:07 GMT
Task Type General Gripe
Category Upstream Bugs
Status Closed
Assigned To Antonio Rojas (arojas)
Architecture All
Severity Low
Priority Normal
Reported Version
Due in Version Undecided
Due Date Undecided
Percent Complete 100%
Votes 0
Private No

Details

Description:
The old stable MLT version 6.4.1 does only use one thread to render the video preview in Kdenlive.
This is fixed in newer versions of MLT (6.5.0-git).

The official AppImage of Kdenlive contains MLT 6.5.0 (from git), the flatpak uses MLT 6.5.0, the official Ubuntu PPA has MLT 6.5.0. So the Kdenlive devs seem to recommend and promote the current MLT git version more than the latest stable one. The git version works better with the newest Kdenlive and ffmpeg versions. And it also fixes this single thread video preview bug. So maybe Arch should do it like the AppImage, flatpak and Ubuntu PPA and provide a git version of MLT? What do you think?

Alternative we could search for the commit that fixes this and patch the latest stable MLT version with it and make mlt 6.4.1-9. But since the AppImage, flatpak and PPA also uses a git version of MLT, so Kdenlive seems to be made for MLT git, I would recommend that Arch should also use a git version of MLT.


Additional info:
using mlt 6.4.1-8


Steps to reproduce:
1. Install Kdenlive (also installs mlt as dependency)
2. Load a high quality video into it and try to play the timeline.
It won't be smooth because it uses only 1 cpu thread to render the preview.
This task depends upon

Closed by  Antonio Rojas (arojas)
Monday, 15 January 2018, 19:07 GMT
Reason for closing:  Fixed
Additional comments about closing:  mlt 6.4.1-9
Comment by loqs (loqs) - Sunday, 14 January 2018, 21:54 GMT
Possibly https://github.com/mltframework/mlt/commit/0f8e807aa911c53e221e940556370ee983f49c64
Just to note while investigating I encountered a checksum mismatch
==> Validating source files with sha256sums...
mlt-6.4.1.tar.gz ... Passed
kdenlive-crash-on-exit.patch ... FAILED
mlt-glibc-2.26.patch ... Passed
==> ERROR: One or more files did not pass the validity check!
Comment by Doug Newgard (Scimmia) - Monday, 15 January 2018, 00:12 GMT
Best option here would be to get MLT upstream to make a release. Have you tried that?
Comment by Antonio Rojas (arojas) - Monday, 15 January 2018, 08:10 GMT
Please test 6.4.1-9
Comment by Elias (Bleuzen) - Monday, 15 January 2018, 19:01 GMT
6.4.1-9 fixed it, thanks :D

However, I also asked the MLT devs how the progress of a new release is. It will be "before end of the month".

Loading...