I am facing crippling performance issues that I did not see when using Kdenlive one year ago. My use case is quite simple; my video is a narrated PowerPoint. I create a PowerPoint presentation and screenshot each slide. I then use Kdenlive to combine these .png images with an audio file created using Audacity. A year ago, I had no problem creating videos with more than 400 images. With the current version of Kdenlive, with just over 100 images, I find crippling performance issues when putting images onto the timeline and using the mouse to change the duration to match the associated audio file. Saving and reloading helps performance a little bit, but not much. Are there any suggestions other than using an old version of Kdenlive (I don’t need fancy features)?

there was not a lot of changes on timeline management on last year...i think you are using the Windows version of kdenlive (right?) .. can you do 2 videos ( one on the old version and one on the new version of kdenlive) and open a performances issue here? : https://invent.kde.org/multimedia/kdenlive/-/issues

if you are on windows, "sharex" software can grab screen (cerating small files) that can be added to the issue to make some measurement on speed lost.

also.. maybe if you can share a project (without images... just the project) this can help

@bartoloni, thanks for your reply.

I am using Windows 11 on a relatively new Lenovo laptop (8GB RAM).

I have uninstalled the current version of Kdenlive and I have installed version 21.04.03. Using the older version, adding .jpg to the timeline and changing the duration of the image is relatively responsive (much, much better than the current version). Of course, when switching to the older version, I had to re-enter all my images as the project file created using the current version was not compatible with the older version.

I am perfectly happy to remain at the older version, as I do not need any fancy features.

I downloaded ShareX but got confused by the user interface.

You wrote "share a project (without images... just the project)". Here is a link: https://1drv.ms/u/s!AmSyQV2bVzZrgeMOLMA ... w?e=8ufAH3

what resolution are these PNG? can you share one?

I am creating a 30-minute video with 300 .png images. Each .png image is created by doing a PrtScr of a PowerPoint slide, so each .png is 1920 pixels x 1080 pixels (matching my screen). The size of the .png will vary with the content of the slide, but the 300 images total 66 Meg giving an average size of 220Kb. My .png do not include any photographs, only text and diagrams, so they tend to be relatively small.

Here is a typical .png: https://1drv.ms/u/s!AmSyQV2bVzZrgeMPfhN ... g?e=JKl7BU

for what i can see, seems that this is related to spacer tool... other things works fine on latest build ...
there is an openend issue about this: https://invent.kde.org/multimedia/kdenlive/-/issues/963

https://invent.kde.org/multimedia/kdenl ... IF6MdD.mp4

I am happy to remain at version 21.04.03 as I do not need any fancy features.

Here is the observed behaviour (it may help identify the root cause):
Initially loading the 30-minute audio file and 300 small .png images has no issues.
Initially dragging and dropping the .png images and adjusting duration of images to align with audio content has no issues.
After about 150 to 200 .png images have been added to the timeline, performance degrades quickly (dragging, dropping, and adjusting duration becomes laggy).
Quitting Kdenlive and restarting the same project causes performance to improve, but performance quickly degrades as more .png images are added.
After a few rounds of quitting and restarting Kdenlive to add more images, performance remains degraded.

I am happy to share all the files from my project if it will help with the debugging.

The following may help whoever tries to address this issue.

At the beginning of a project, everything works fluidly. In other words, loading 500 images into the Project Bin is not an issue.

Once more than a couple hundred images have been placed on the Timeline, clicking on a new image from the Project Bin and having it appear in the Clip Monitor becomes very laggy. Once an image appears in the Clip Monitor, placing it on the Timeline is still fluid (no lag).

If I quit and restart Kdenlive, the lagginess of clicking on a new image from the Project Bin and having it appear in the Clip Monitor improves somewhat, but quickly starts to degrade again as more images are added to the Timeline. Again, once the image is displayed in the Clip Monitor, no problem dragging it to the timeline and manipulating duration, etc.