Overall: I cannot get valid thumbnails for youtube live streams (about 40% to 50% of streams ' thumbnails I get back are invalid/404 - gray "no screenshot" image) when pulling from the API v2.
Details: Here is what I am using to grab the streams:
https://gdata.youtube.com/feeds/api/charts/live/events/live_now?v=2&alt=json&inline=true&max-results=20&start-index=1&fields=entry(published,updated,title,author(name),content(entry(media:group)))
Within "media$thumbnail" I am getting data (6 thumbnail items), and on half the entries it gives me the gray "no screenshot" icon for all 6 screenshots. The other half usually gives me back half valid thumbnails and half invalid. So I may get back the default images (high def and regulars), and it won't give me the numbered images (0.jpg, 1.jpg, 2.jpg, etc.).
I have tried using the only two variations of url that I know of:
http://i.ytimg.com/vi/[VID-ID]/default.jpg
http://img.youtube.com/vi/[VID-ID]/0.jpg
From the live stream site, there are no invalid thumbnails which to me would suggest that all live streams have a valid thumbnail, or does that mean that youtube does not show streams that do not have valid thumbnails? I also noticed that they switch quite a bit between using 1.jpg and default.jpg, is there a way though the api to tell which image is preferred?
Thanks for any help on this subject!
Jake
So it looks like you're seeing this with video ids that correspond to "Hangouts on Air", which are Google+ Hangouts that are broadcast live via YouTube. They use a different setup than normal scheduled YouTube Live events, and you can't, for instance, create a thumbnail in advance of the broadcast (since the live event is created on the fly).