+ move to GraphicsMagick (supports multi-core)
+ display pictures (slides) while editing
+ calculate exact pre-roll timeout for OSD
++ jump to correct position in subtitles.srt.yaml on F12
+- render subtitles with slide mark [42] in html
+- convert all media/*/www to mirror www.sh script
- render carousel slides as png
- fork new process for HTML::Slide which then can have real SDL event loop