About Auto-generated Preview Images (Thumbnails)
During transcoding of a video, Backlot generates thumbnails of the video at 15 second intervals.
When a video is uploaded to Ooyala, Backlot produces a series of thumbnails (also known as a "preview image") for each encoding, regardless of type of encoding.
By default, a thumbnail is taken at 15-second intervals throughout the length of the video. If you want to change this interval, contact Ooyala Technical Support.
Thumbnails are sized at 1/3 of the encoding width.
However, the "preview image" is a global setting per video. Only one of the generated thumbnails (or one of the custom uploaded preview images) can be set as the one that is displayed in the player preview. By default, this is the first thumbnail from the highest-resolution encoding.