Non-iterative and spatial domain focus map estimation based on intentional re-blur from a single image (NasBirSi)

Transforming conventional pre-existing 2D content is still a necessary technique for utilizing pre-existing content for stereo vision. In this paper, a spatial domain focus map estimation algorithm based of an intentional re-blur on a single image, which is the only input data, is presented. The proposed intentional re-blur amplifies the blur in the original input image, and the value of our proposed ratio map is the ratio of the gradient magnitude of the intentional re-blurred image to the gradient magnitude of the original image. The edges of the original input image were re-blurred such that the widths of the edges on the ratio map differ. According to the theoretically derived results and the observations of the example used, the widths of the edges on the introduced ratio map were found to be related to the distance of each object from the camera focus. The pixels close to the focal point of the camera are on a thinner edge. In contrast, the edges are wider when the pixels are farther from the focal point. We utilized this discovery to derive the final focus map, whose enhanced effectiveness, quality, and precision were demonstrated experimentally.