Framerate override for multiple files in the project bin? (GoPro slo motion)

Help
1

I have a GoPro that has a “4x Slo Motion” option. This seems to create footage that’s 120FPS, which is meant to be played at 30FPS for a slo-mo effect…

I have created a project in Kdenlive that is 30FPS.

When I import the footage and preview it, or put it on the timeline, Kdenlive keeps the video length and drops the extra frames. This is not the desired effect.

I want to import 120 FPS footage into the 30FPS project and have Kdenlive import every frame, just make the resulting clip longer to accommodate that.

I know there is an option to speed up or slow down a clip, but I’m not sure that is what I want.

I found a tab for clip properties, and it shows the clip is 119.88, with the option to tick a box and make it a different frame rate. I presume I should make it 29.97 not 30, and set the project to 29.97 when using this type of clip?

This seems to work. But even if I select all the clips in Project Bin then set the frame rate in the Clip Properties tab, it seems to only set the frame rate for one of the selected clips, not all of them. Is there a way to set this for all clips at once? Or make this a project level default?

2

So I tried the above, and I’m having a problem. When I change the clip from 119.88 to 29.97, the duration of the clip does not change. This means that I can only use the first 1/4 of the clip in the project. I can’t make the clip any longer. The option to set duration in clip properties doesn’t seem to be working. I can change the numbers, but as soon as I click off the numbers, it jumps back.

So the clip is 00:00:46,21 @ 119.88. And if I change the frame rate to 29.97, it is then 00:00:46,21 @ 29.97, and the last 3/4 of the clip isn’t usable in the editor.

If I try to change 00:00:46,21 to anything else after ticking the duration box, it just jumps right back to 00:00:46,21 after I click out of the edit field.

So I don’t know if this is a bug? Or is there something else I can try?

3

I suggest indeed to create a bug report in bugs.kde.org

4

I just read up in clip properties in the Kdenlive documentation and the duration should be changeable. So it is definitely a bug.

5

Bug reported here:

https://bugs.kde.org/show_bug.cgi?id=468697