Depth from defocus by zooming using thin lens‐based zoom model

Abstract

AbstractIn past depth from zoom methods, the pinhole camera model has been used, and the depth has been measured by moving the pinhole position by zooming. This paper describes a method of estimating the depth from the change of blur depending on the zoom shift, in the same way as in the depth from focus/iris methods, where the depth is estimated from the change of blur. As the first step, a thin lens‐based zoom model is discussed, which describes in a unified way the relations among the zoom, focus, and iris of the zoom lens systems. In the proposed camera model, the effective focal length and the effective lens diameter are functions of the zoom, focus, and iris. The blur model is derived from these relations. Then, a method is described in which the depth is measured from the width of the edge blur. The experiment using a real image shows that it is possible to measure the depth stably from multizoom blur images. Lastly, we present an example in which the depth information obtained by the proposed method is applied to image synthesis. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 89(9): 53–62, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20300