The following custom thumbnail best procedures for movie image dimensions and determination are presented: “Your custom thumbnail picture should be as big as you can, given that the picture may even be used as the preview graphic in the embedded player. We endorse your custom thumbnails: Google’s Picture Guidelines say, https://www.presta-addons-modules.com/en/opencart-seo-automatic-google-rich-snippets-json-ld-integration-opengraph-twitter-tags-schemaorg.html