How to get a thumbnail or snapshot of a youtube video at a specific "second" with Youtube javascript API?

youtube, youtube-api, youtube-javascript-api

Solution

Those specific type thumbnails (used for the timeline snapshots) are not exposed via any sort of official URL scheme or API. I wouldn't recommend trying to reverse-engineer a solution, either.

Problem

I want to take a thumbnail image of a youtube video, let's say http://www.youtube.com/watch?v=ffaTjpA1scI at 30s or 120s. How can I do that with youtube API? I do think this is possible, because when I watch a Youtube video, if I move my cursor to the timeline, I can immediately see snapshots at specific time. I just want to retrieve these snapshots programmatically. I also tried http://img.youtube.com/vi//0.jpg, actually this can get the thumbnail of course, but it cannot get a snapshots at a specific time.

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