I am using 17.12.3 on Kubuntu 18.04.

When I drag my mouse along the timeline, the result in the Project Monitor is inconsistent. For example: at a certain second:frame, the scene changes in a single clip. Every time I drag my mouse along the timeline, the specific second:frame when the scene changes varies by nearly three seconds.
One time the scene will change at exactly 00:17,20, but the next time I try to click that exact frame on the timeline, the Project Monitor still shows the previous scene, and I have to drag the cursor three seconds to the right before my preview indicates the scene has changed. I am using mp4 files in my project, and I only have five tracks.

Frame-by-frame accuracy is extremely important for clip cutting and transitions. I thought perhaps I am using a less-supported file extension, and I'm of course willing to convert to the best file type to get an efficient project, but I looked up the section of the online manual about importing, and the entry is entirely blank (?)

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

Any idea what's going on here?

P.S. - I wouldn't think this is a question of horsepower. I'm at work on a video editing machine:
Here's my specs: http://tinypic.com/r/9bgg08/9

Make sure GPU acceleration is off. Please try with the current Kdenlive AppImage version 18.12.1b https://files.kde.org/kdenlive/release/. If it’s still appearing then it’s the MP4 file. See here Video Not Displayed Differently on Rewind.

Merlimau wrote:Make sure GPU acceleration is off.

Thanks for the response. How do I do that?

Hit CTRL+SHIFT+, (comma) -> Playback -> un-tick “use GPU processing”.

The link to "See here Video Not Displayed Differently on Rewind.": viewtopic.php?f=265&t=155457

Looks like "use GPU processing" was already un-checked. So, I checked it (since I'm using a gtx960), and it was WAY worse. So, on or off, that unfortunately doesn't solve my issue.
Also, that link you posted, you didn't really offer a solution there. You simply stated why KDEn has a hard time with mp4s.

Does some other file extension besides mp4 work better with KDEn? If so, which one? mov? mkv? avi?

Thanks for your time.

Sorry for my inaccurate answer. MP4 tested with the AppImage 18.12.1b and the Windows version 18.12.1. Yes there are strange “jumps” when you play backwards using the arrow key.

The solution I found to get always the same frame: play always forward, stop before the desired cut and then use the right arrow key to find the frame. In my test it finds always the same picture at the same frame number.

To describe this effect I posted the link to the other thread. The last post descripts this effect.

Thank you again. Are there any suggested video file types that I could use where this anomaly doesn't occur? Does KDEn perform better with avi, for example?

MOV and MKV are containers which can host MPEG4 as well. AVI is an old Windows format. I cannot recommend any of these formats for better working in Kdenlive because you convert a compressed format into another compressed format. What you can try is with proxy clips if they are better for cutting. I have never worked with proxy so far.

Hello,
The problem is not with container but with codec: it is much easier to seek streams that contain only "I-frames" (full image each time, no difference from picture to picture): h264 can do it with GOP size of 1 (as in "lossless" profiles), but "intermediate" codecs like DNxHD, ProRes or MJPEG are namely made for that.