I am trying to edit HD game captures and the raw video plays back on my system perfectly, however for some reason WITH NO EFFECTS AT ALL Kdenlive plays the clip at a few fps at best. why is playback so poor and what can i do to fix it, i have tried giving melt more threads, using gpu playback. I saw various threads saying use preview rendering, sure those playback smooth but it only does small little clips and sections, and it can be slow i am not going to wait for the entire video to render out a preview that is insane. I have a 5820k clocked to 4.5Ghz and 32GB of ram with a m.2 SSD that has 2.5GB/s read speeds there is no acceptable reason for Kdenlive to not be able to play this clip smoothly.

Here is a recorded example of what i mean,
https://greendogcustoms.net/f/35a4a1d1d6e34e01b2d0/

Naturally i cant edit a file if seeking through it is pretty much impossible. Using Kdenlive version 17.08.1

Hello,
Are you on Windows or Linux?
Are you editing HD or 4k material?
Sure your system is impressive, I can edit HD on a 10 years old Core2 laptop

As we are using OpenGL display, performance depend much on video driver...
Windows version is not much tested/debugged yet, and our Qt build relies on native windows OpenGL implementation.
Other projects report better performance using DirectX wrapper, but as I cross-build the binaries from Linux this is quite difficult to setup

Hi thanks for the response, as you can see in the video example i posted i am on Linux. I am using the nvidia drivers version 387.12. I am editing 1080p 60fps footage. I have tried as i mentioned using more threads in the environment settings, this seems to help video slightly (and i do mean slightly, from 1-5fps to maybe 10fps) but causes audio to desync. Using GPU processing seems to make no difference either way.

Here is some of my OpenGL info

[kitsuna@Kitsuna-Desktop ~]$ glxinfo | grep OpenGL
OpenGL vendor string: NVIDIA Corporation
OpenGL renderer string: GeForce GTX 970/PCIe/SSE2
OpenGL core profile version string: 4.5.0 NVIDIA 387.12
OpenGL core profile shading language version string: 4.50 NVIDIA
OpenGL core profile context flags: (none)
OpenGL core profile profile mask: core profile
OpenGL core profile extensions:
OpenGL version string: 4.6.0 NVIDIA 387.12
OpenGL shading language version string: 4.60 NVIDIA
OpenGL context flags: (none)
OpenGL profile mask: (none)
OpenGL extensions:
OpenGL ES profile version string: OpenGL ES 3.2 NVIDIA 387.12
OpenGL ES profile shading language version string: OpenGL ES GLSL ES 3.20
OpenGL ES profile extensions:

and here is some more information about my system in case its relevant or helpful.
4.12.14-1-ck-haswell #1 SMP PREEMPT Wed Sep 20 16:33:00 EDT 2017 x86_64 GNU/Linux
KDE Plasma Version 5.11.0
Framework Version 538.0
QT version 5.9.2


I am not sure if this would cause a problem however i just ran kdenlive from cli to see if i got anything and this came up
mlt_repository_init: failed to dlopen /usr/lib/mlt/libmltsox.so
(libsox.so.3: cannot open shared object file: No such file or directory)

Just out of curiosity, how smooth it is if you play your file in melt ? ("melt video.mp4")

Other than that, I highly recommand that you look into proxies to smooth it up a bit

alcinos wrote:Just out of curiosity, how smooth it is if you play your file in melt ? ("melt video.mp4")

Other than that, I highly recommand that you look into proxies to smooth it up a bit

Looks like direct melt also plays at horrible speeds. So i suppose the issue lies with melt at this point. and as i already said in my original post i am aware of proxy, however i dont want to wait for proxy renders while trying to seek around 6+ hours worth of footage which is what i usually need to work with and find clips from. It is also a poor solution since this is a stupid problem. The fact that melt is having issues playing back a simple 1080p 60 file that no other video player is having issues with makes me question why Kdenlive is even using it.

Well after tons of messing with settings to no avail and no help here other than "just use proxy" i have moved to openshot. I would have liked to stick with Kdenlive as i like the KDE software suite so far but if i cant even get a basic file to do playback in the timeline its useless and i sure as heck cant try to recommend it to people.

Sorry we couldn't help you much, as "it just works here" (1080p@25Hz on Core2/4GB RAM)...
OpenShot 1.x also uses MLT, so if melt has the problem you won't get any further; OpenShot 2.x is a huge rewrite effort still not yet fully completed to my understanding, do you find it usable for your purpose?
One more question: are you on Wayland? (probably not as Nvidia drivers don't offer adapted modesetting)

vpinon wrote:Sorry we couldn't help you much, as "it just works here" (1080p@25Hz on Core2/4GB RAM)...
OpenShot 1.x also uses MLT, so if melt has the problem you won't get any further; OpenShot 2.x is a huge rewrite effort still not yet fully completed to my understanding, do you find it usable for your purpose?
One more question: are you on Wayland? (probably not as Nvidia drivers don't offer adapted modesetting)

I am indeed using the new branch. Version 2.4.0 and it is working, it stutters a little but its more than usable and i can actually seek through the timeline without it getting stuck. You can see a demo of what i mean here no i am not using Wayland, i would love to try to work this out with you guys if i can as i would be happy to help track down issues. What other information would be useful to you?