[kdenlive] Copying Kdenlive projects and Preview Rendering

[jb]

Le 20.06.16 à 12:14, Harald Albrecht a écrit :
> Hi,
>
> just want to ask here before filing a bug report: just started work on 
> two new Kdenlive projects. For convenience, I cloned the first project 
> in an early stage to be used as the starting point for the second 
> project. And then I noticed something concerning preview rendering...
>
> 1. While working on the first project, I preview rendered the first 
> few seconds consisting of the titling for this episode #23. So far, so 
> good.
>
> 2. Then worked on the second project and replaced the title for this 
> separate episode #24. Now, the fun starts: when preview rendering the 
> same zone for the titling, Kdenlive happily picked up the preview 
> rendering from episode #23, which I can clearly see as preview now 
> uses the wrong titling.
>
> So, this brings me to my question: does the document identity 
> correctly change when I copy a project?
>

Good question! I also thought about it and have not found a solution yet.
The project id is created when the document is first created and 
consists of a timestamp.
This timestamp is then used to create a temporary folder in 
$HOME/.cache/kdenlive, and the audio/video thumbnails and preview files 
are stored in this folder.

This way, the project file can be renamed / moved without losing the 
temporary data. However if you create a copy of the project (either to 
try a different edit or to start a new project based on the current 
one), the document id is not changed, so the same temporary folder is 
used, leading to potential conflicts of preview files (but on the other 
hand it can be nice to have the audio/video thumbs already created).

I cannot think of a way to automatically handle this...

Maybe we could introduce a "clone" feature that would set a new document 
id and copy temp data to that new folder ?

Any idea/comment is welcome.

jb

> Best regards,
> Harald
>
> PS: As always, doing actual projects on the bleeding edge...