Feature Request Video Export 2.0

[sonejostudios]

Hello senshu!
I made some improvements for my needs in sozi-to-video on my local machine. For now they still are under testing, and I will come with a pull request as soon as I'm done with my sozi project. Here is a list of the improvements, some of them you have implemented already (in a much smarter way than I did already), some are coming in my pull request, some I'm not able to achieve (I have no clue about javascript, just a little python).

What it is done by you so far (thank you!):

• cli option to export .png files only
• cli option to set up temp folder

What I also implemented in my version:

• cli option to setup encoder (for the people using ffmpeg insted of avconv)
• cli option to set up the frame/sec of the encoder. (and: -> see next point)

What I would like to implement (but not able to):

• I would like to correlate the frame/sec option with the TIME_STEP_MS variable, so the number of png files will match, but I couldn't achieve to pass the option in the sandboxed function. (1 sec/frame per sec - option)*1000. I think 25 progressive frames/sec could also be a default value since this is much more common in video editing than 50/s and it also generate less pictures, but this is not important, only important is to have the option to set it up in the cli :)
• (SOZI) an option in .sozi.html file to set up .sozi-frame-number color and background-color with alpha = 0.0, so it it will not be visible and therefore not exported in the video.
• a cli option to set a kind of "sleep=sec" function into the main export loop, so the export process will be slower. I need this since javascript/sozi is not able to do multithreading, it starts exporting like crazy and if you have a long presentation, the cpu will overheat. (I want to export in High Definition and my computer crashes by every export right now because of overheating).
• or a cli option to set start frame and end frame, it it would be possible to export an animation step by step (and therefore not overheating the cpu).

That's it :)
Please let me know if you can do it, I will try also on my side and come to you if I can achieve something.

All the best,

Vince