Method and apparatus for auto-focus control of digital camera

摘要

Disclosed is a method for auto-focus control of a digital camera, the method including moving a focus lens of the digital camera to a position for a longest-distance photographing, and then extracting an edge value according to a corresponding position while moving the focus lens by a preset interval in a direction toward an image sensor; estimating a form of a preset function based on the extracted edge values, and calculating a maximum value of the estimated function; calculating a difference between a maximum value of the preset function calculated at a first current position of the focus lens and a maximum value of the preset function calculated at a previous position of the focus lens; and moving the focus lens to a position corresponding to a currently-calculated maximum value of the preset function when the difference between the maximum value of the preset function calculated at the first current position of the focus lens and the maximum value of the preset function calculated at the previous position of the focus lens is less than or equal to a preset threshold value.