get
This should return a thumbnail associated with the provided timestamp of the provided item. The reason this function does not simply return a Uri to a bitmap is that some platforms like Youtube provide the preview thumbnail as a collage of multiple thumbnails within one jpeg file. It is then the task of the client to crop this jpeg to only show the piece of that image that depicts the thumbnail for the given timestamp.
So because of this you will have to download, or precache, the thumbnails by yourself.