I'm running version 15.12.1 from Sunab's release repository on Ubuntu GNOME 15.10. I'm really impressed with how good things are getting.

My one issue is that if I've got layers composited together (e.g. an image overlayed on top of a video playing) my in-editor playback framerate goes all the way down to about 14 fps. (I'm working with 720p, 30 fps video.)

My rig seems pretty decent, I think? I've got a 6-core AMD Fx-6300 processor, I'm using an SSD and I've got 8 GB of RAM.

I've tried using proxy clips at half resolution but it doesn't change the project monitor's performance dip that seems to come with every clip that has anything composited on top of it.

Is there any way to optimize for a higher playback framerate? If I can get good performance there I could probably use Kdenlive for all of my editing needs.
OR if there was some sort of way to temporarily render sections of the project (a la Final Cut) that would be cool too.

https://userbase.kde.org/Kdenlive/Manua ... roxy_clips

ttguy wrote:https://userbase.kde.org/Kdenlive/Manual/Projects_and_Files/Clips#Proxy_clips

Thanks, but I've already tried using proxy clips. I actually mentioned it in my original post. The proxy clips I've tried were 640x360 and I somehow still get low framerates when compositing.

Here's a screencap (taken from the SVN version of Kdenlive, 16.07.70)


As you can see, I'm only putting one PNG image on top of a 640x360 proxy clip and I'm still getting a low playback framerate when there are multiple layers being shown. (Target framerate for the project is 30 fps.) The proxy clips don't seem to affect framerate at all for me.

The framerate is good when I just have the clips in the timeline with nothing in the layers on top of them.

How do you overlay the tracks? If you use the Affine transition, you should give Composite a try. If that does not help, let us know how many tracks you want to overlay and which effects and transisions you use (and how many of them).

capslock wrote:How do you overlay the tracks? If you use the Affine transition, you should give Composite a try. If that does not help, let us know how many tracks you want to overlay and which effects and transisions you use (and how many of them).

Wow! That makes a huge difference!

I wasn't using transitions. I added the Composite transition and it brought the framerate right back to where it should be.



I don't know why Kdenlive doesn't default to using Composite transitions when you put clips on top of each other. If you overlay tracks without transitions it really kills the framerate. I guess I'll just file a bug report for that if there wasn't one already, though.

Thank you so much! This is the thing I really need to make Kdenlive suit my workflow.

Okay, so that seems to work well for just compositing two clips, but for three clips or more it seems like there's still a pretty noticeable drop in framerate.

Do you have any recommendations for getting better playback performance when compositing multiple clips at once?