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Extract image links from youtube videos
This is the default thumbnail for the video. Default Image Size is: 120x90
This is the medium sized one. HQ Image Size is: 480 x 360px
Max Size Image
This is the big one, if the video is high enough resolution or one is manually uploaded it will usually provide the image size of 1280 x 720 pixels. This may be increased if the image provided is a higher resolution.
There is usually three additional thumbnails generated from the video. Unless they are specified they will pick certain elements from the videos.
https://img.youtube.com/vi/o4QcmHcKdk8/1.jpg https://img.youtube.com/vi/o4QcmHcKdk8/2.jpg https://img.youtube.com/vi/o4QcmHcKdk8/3.jpg
Also known as MQ Default this one is a bit bigger than the previous thumbnails.
Finally here is the embed iframe code for the video if you want to include it into your pages.
<iframe width='100%' height='420' src='https://www.youtube.com/embed/o4QcmHcKdk8?rel=0' frameborder='0' allowfullscreen></iframe>