Further developments on `HeadCam´: joint estimation of camera rotation+gain group of transformations for wearable bi-foveated cameras

An eyeglass-mounted camera system with wearable multimedia computer (`WearCam´) was previously proposed. In particular, `WearCam´ contains two miniature cameras: one (wide-angle in landscape orientation) provides the overall contextual information from the wearer´s perspective, while the other (telephoto, in portrait orientation) provides close-up details, such as faces. This `bi-foveated´ scheme was found to work well within the context of a proposed model of image motion characterized by a projective (homographic) coordinate transformation together with a gain transformation. Applications of `WearCam´ include personal safety (crime prevention and personal documentary), perceptual intelligence/situational awareness (in the context of personal wearable multimedia), and homographic modeling (wearable, tetherless computer-mediated reality). A pencigraphic image representation is presented where the photometric response function of the camera is determined to within a constant, and the registered images are assembled into a photometric environment map, yielding an estimate, to within a constant scale factor, of the number of photons of light coming from each angle, toward the wearer