Patent attributes
A method for photogrammetric measurement includes providing a bedsheet having one or more patterns printed thereon in accordance with a pattern template, which defines respective locations of the one or more patterns in a template coordinate frame. An image is received, in an image coordinate frame, of a person lying on a bed, which is covered by the bedsheet. The image is processed in order to identify the one or more patterns in the image and to match the one or more patterns identified in the image to the one or more patterns in the pattern template. A transformation is computed, based on the matched patterns, between the image coordinate frame and the template coordinate frame. A dimension of the person is measured by applying the computed transformation to the image of the person.