What are Video Posters?
Video posters are still images shown before playback begins or while video data is unavailable. A poster should represent the content clearly at the dimensions and crop used by the player.
How Video Posters work
A poster is fetched and painted independently of the video frames, allowing the player to reserve a visual state before decoding begins. The chosen image often passes through the same image-derivative pipeline as thumbnails, with alternate sizes or crops for different layouts. It is distinct from an in-stream first frame and may remain visible when media loading is deferred. Poster production belongs near publishing, after editorial selection and before the page or app is rendered.
Key facts
- 1The poster’s intrinsic dimensions and the player’s aspect-ratio and object-fit rules determine cropping; mismatched ratios can remove faces, text, or other key content.
- 2Video frames replace the poster once playback starts, but when loading or decoding fails, browsers commonly leave the poster visible with no error affordance, so it should not be relied on to communicate an unsupported codec or a decoder failure.
- 3The video element does not give its poster an independent alternative-text field; nearby titles, labels, captions, or transcripts must provide accessible context.
When Video Posters matter
Select a poster that remains recognizable in both catalog cards and the full player. Missing dimensions or unsuitable crops can cause layout shifts, obscure subjects, or misrepresent the video.