摘要 |
An auto focus image system that includes a pixel array coupled to a focus signal generator. The pixel array captures an image that has at least one edge with a width. The focus signal generator may generate a focus signal that is a function of the edge width and/or statistics of edge widths. A processor receives the focus signal and/or the statistics of edge widths and adjust a focus position of a focus lens. The edge width can be determined by various techniques including the use of gradients. A histogram of edge widths may be used to determine whether a particular image is focused or unfocused. A histogram with a large population of thin edge widths is indicative of a focused image. Edge corruption/partial corruption may be detected. Partially corrupted edge may have edge width calculated by relying more on the side that is not corrupted and less on the side that is corrupted. Edge or edge side corruption may be detected by detecting a presence of an adjacent edge of the opposite sign. |