Video thumbnails: If the merchant chooses to add video thumbnails to a video, they can upload it via admin. If they don't, the video image is going to be pulled from the actual source (eg. Youtube) and there is a chance that it might be blurry.
The most commonly used aspect ratio for videos is 16:9. An inverse ratio is popularly used for social media platforms with video editing capabilities (eg. instagram, facebook) The most common dimension in this aspect ratio is 1080×1920 pixels, which equates to a smartphone’s vertical screen size.
Usage of 16:9 aspect ratio is 2.7% for non-product images.