1. An apparatus, comprising: an image sensor configured to capture image data of a scene; a memory comprising a buffer; and at least one processor coupled to the image sensor and the memory, the at least one processor configured to: receive and store the image data captured by the image sensor in the buffer as a current frame of the scene; divide the current frame of the scene into a plurality of windows, each of the plurality of windows corresponding to a different spatial region of the scene; identify a central portion of the current frame, the central portion comprising a subset of the plurality of windows; determine a first depth value of the central portion based on performing phase detection autofocus (PDAF) on the subset of the plurality of windows; and determine a confidence value for the central portion based on the first depth value and image data corresponding to the subset of the plurality of windows.