Lighting and expression
Soft window light or open shade usually makes facial details easier to see than strong backlight. Avoid dark photos, blown-out highlights and colored lighting that obscures skin and facial structure.
A neutral expression or a gentle smile is a useful starting point. Sunglasses, a hand across the face or heavy filters can remove details the model needs for a consistent result.
Framing and file requirements
Use JPG, PNG or WebP, with a file smaller than 8 MB. Image edges must be between 300 and 6000 pixels, and the width-to-height ratio must be between 0.4 and 2.5. A normal portrait crop fits these limits.
Show the whole face and enough surrounding hair and neck to give context. Do not enlarge a tiny blurry picture just to meet the minimum dimensions; more pixels do not restore missing detail.
Understand the two checks
The browser validates the file and can warn about low brightness before upload. It does not prove identity, count people reliably or guarantee that the portrait will pass provider review.
The service then reviews the portrait as a private asset before video generation. If the portrait is rejected, try a clearer photo of one consenting adult. Confirmed failures return any credits charged for that task.