Export produces videos with black background when editor shows white background

[colindean]

Summary of your problem or feature request

When I export any of the examples to video in MP4 or WEBM format, the background of the slides is black instead of white. This means the colored elements are visible but the text is not

Version of Sozi and other relevant software

• Which version of Sozi are you using? 22.03.25-1648241936 freshly downloaded
• Which drawing software did you use? The Sozi-demos repo
• On which platform? Windows 10 and Linux (via ChromeOS)
• If your problem happens when playing a presentation, which browsers have you tried?

Steps to reproduce the problem

Open the 'this is not a slideshow' demo svg and export it, changing no settings perhaps other than the output format.

Expected behavior

White background, not black background when replayed in VLC.

Observed behavior

Actual export file:

this-is-not-a-slideshow.sozi.webm

The output is black for both formats in VLC, Firefox, and Windows Movies and TV as well as in ChromeOS's video player.

Hints and solutions (optional)

I've not actually looked at the SVG input to know if the background is explicitly white. I'm wondering if it's a transparent background and the screen captures that appear to be capturing the animation frames are not capturing a white background but transparent instead.

[colindean]

What's fascinating is that at least for the webm format that Github allowed me to upload, the background is transparent when replayed in Firefox:

[colindean]

Playing around with an SVG of my own creation, this appears only to affect the examples. I speculate that their background color is not explicitly set.

[ejvindh]

Until more qualified feedback appeas, maybe a hint that you can work with: At some point I had a similar issue when exporting svg's to powerpoint. I then investigated the issue, and found that there was a bug in one of the underlying libraries. I then solved it by changing the exporting from png to jpg (or maybe it was the other way around...).

I don't think there should be a need to define background color in your svg.