摘要 |
<p>An auto focus image system that includes a pixel array coupled to a focus signal generator. The pixel array captures an image that has a plurality of edges. The generator generates a focus signal that is a function of a plurality of edge-sharpness measures measured from each of the plurality of edges. The generator compares a sequence of gradients across the edge with one or more reference sequences of gradients and/or reference curves defined by data retrieved from a non- volatile memory. The generator determines to reject or de- emphasize the edge from contributing to the focus signal on basis of finding dissimilarity between the sequence of gradients with the reference sequences or reference curves beyond a predetermined threshold.</p> |