Video is an old problem, so searching will throw up lots of posts. Years ago, we had a post on our old website that showed an overview of video tests that we had run. It's here as PDF:
http://files.interaktiv.co.uk/opuspro/o ... ormats.pdfBasically, Opus will need access to a system codec as it doesn't have it's own - licensing issues I guess.
You'll need something like QuickTime for MP4.
If you don't want a third-party codec, then WMV is probably the best choice for high quality video available on most systems.
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