This is one of those idealistic W3C specifications with super messy implementations all over.
EMBII by Ciro Santilli 37 Updated 2025-07-16
One of the dudes from the AtomSea & EMBII Bitcoin-based file upload system.
Figure 1.
EMBII's usual profile image
. Source.
WikiAlpha by Ciro Santilli 37 Updated 2025-07-16
WikiAlpha is an alternative to Wikipedia, where the main difference is that our deletion policy is far more lenient with regard to notability requirements. Basically, WikiAlpha is a near-indiscriminate collection of information in the form of articles on any topic: you can create an article about the band you just started, your pet dog, yourself, your house - as long as your content does not fall under our speedy deletion policy, it will likely remain on the site forever!
Delft OpenCourseWare by Ciro Santilli 37 Updated 2025-07-16
They have a lot of stuff, well done.
CC BY-NC-SA by default unfortunately, but what can you do...
For synthesized streams like sine we can do it e.g.
ffplay -autoexit -nodisp -f lavfi -i '
sine=frequency=500[a];
sine=frequency=1000[b];
[a][b]amerge, atrim=end=2
'
but it does not seem to accept multiple -i for some reason. So is there a way to open a file from some filter? E.g.:
ffplay -i tmp.wav -i tmp.mkv -filter_complex "[0:a]atrim=end=2[a];[1:v]trim=end=2[v]" -map '[a]' -map '[v]'
fails with:
Argument 'tmp.mkv' provided as input filename, but 'tmp.wav' was already specified.

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