Bug 491628

Summary:	Stuttery/Very low FPS timeline playback on clips with zero effects
Product:	[Applications] kdenlive	Reporter:	Keith <xanqz5151>
Component:	Rendering & Export	Assignee:	Jean-Baptiste Mardelle <jb>
Status:	RESOLVED WORKSFORME
Severity:	major
Priority:	NOR
Version First Reported In:	24.05.2
Target Milestone:	---
Platform:	Debian unstable
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Keith 2024-08-12 15:28:09 UTC

SUMMARY
Playback is extremely laggy and stuttery on videos of all kinds with kdenlive. On Shotcut or Openshot playback is very smooth even with a few effects thrown in and no proxies.


STEPS TO REPRODUCE
1. Add a clip on the timeline
2. Click Play 

OBSERVED RESULT

Very low FPS.

EXPECTED RESULT

At least 30 FPS for 30 FPS videos or 60 FPS for 60 FPS videos.

SOFTWARE/OS VERSIONS
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: Debian GNU/Linux 12 unstable
KDE Plasma Version: 5.27.11 
KDE Frameworks Version: 5.115.0
Qt Version: 5.15.13

ADDITIONAL INFORMATION
Igpu: Mesa Intel® UHD Graphics 600
Cpu: 4 × Intel® Celeron® N4120 CPU @ 1.10GHz
Memory: 3.6 GiB of RAM

It happens on 720p videos, 480p videos, doesn't matter.

There is high CPU usage, some GPU usage, and 2GB+ RAM usage, but playback is still not smooth. I am not swapping nor running out of memory.

Comment 1 Jean-Baptiste Mardelle 2024-08-13 13:38:53 UTC

Could you please give more infos about the project profile and the size of your video clips ?
Also, please check in Kdenlive Settings that in the "Misc" tab, the "Prefered track compositing composition" is set to qtblend. Then start a new project and check if playback is still bad

Comment 2 Keith 2024-08-14 08:19:32 UTC

> Could you please give more infos about the project profile and the size of your video clips ?

HD 1080p 30 FPS, default preset. 15 minutes.

> Also, please check in Kdenlive Settings that in the "Misc" tab, the "Prefered track compositing composition" is set to qtblend. Then start a new project and check if playback is still bad

This seemed to be the problem and playback is a lot more tolerable now, thank you.

I will still let the bug open, in case some people might want to think about whether some defaults need to be changed (I probably am not the only one encountering the issue).

Comment 3 Jean-Baptiste Mardelle 2024-08-14 18:16:30 UTC

Git commit 02823371753be2c5a8885328204ba99bb5e7ab13 by Jean-Baptiste Mardelle.
Committed on 14/08/2024 at 18:16.
Pushed by mardelle into branch 'release/24.08'.

Ensure qtblend composition is always preferred to cairoblend unless specifically requested by user

M  +2    -2    src/doc/documentvalidator.cpp
M  +1    -1    src/kdenlivesettings.kcfg
M  +1    -1    src/transitions/transitionsrepository.cpp

https://invent.kde.org/multimedia/kdenlive/-/commit/02823371753be2c5a8885328204ba99bb5e7ab13

Comment 4 Bug Janitor Service 2024-08-29 03:47:53 UTC

🐛🧹 ⚠️ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!

Comment 5 Bug Janitor Service 2024-09-13 03:47:10 UTC

🐛🧹 This bug has been in NEEDSINFO status with no change for at least 30 days. Closing as RESOLVED WORKSFORME.