3D dynamic structure estimation using synchronized images

A method for identity verification, the method comprising:

• receiving, by a computing device, first images from a first camera with a first field of view, wherein the first images comprise a human subject and are within the first field of view;
• receiving, by the computing device, second images from a second camera with a second field of view,
• wherein the second images comprise images of an identification (ID) document,
• wherein the ID document comprises a photograph of the human subject,
• wherein the second field of view is in substantially an opposite direction from the first field of view, and
• wherein each image of the first images has a corresponding one of the second images captured substantially synchronously with the image;
• processing, by the computing device, the first images with the respective, corresponding second images to determine a sequence of respective three-dimensional (3D) locations, for at least one of the first camera and the second camera, at the respective times the first images and the corresponding second images were substantially synchronously captured;
• determining, by the computing device based on the sequence of 3D locations, the first images, and the second images, that the human subject is a valid human subject;
• in response to determining that the human subject is a valid human subject and that the ID document describes the valid human subject, performing an action.