Patent ID: 8390732
Filing Date: 2013-03-05
Classification: H04N

Abstract:
1. A method for adjusting a focal length of a camera, comprising: pre-establishing a plurality of graphs according to different light intensities surrounding the camera, each of the plurality of graphs showing a relationship between an image definition and a focal length of the camera under a corresponding light intensity surrounding the camera, and selecting a corresponding graph according to a current light intensity surrounding the camera by an application server, wherein an X-axis of the selected graph represents the focal length of the camera, a Y-axis of the selected graph represents the image definition, a maximum value of the image definition in the selected graph being regarded as a standard definition; sending a captured image from the camera to the application server when the focal length of the camera is adjusted; calculating a definition of the captured image by the application server, and calculating a first difference between the definition of the captured image and the standard definition; determining if the focal length of the camera needs to be adjusted again according to the first difference by the application server; sending the determination result from the application server to a mobile device; adjusting the focal length of the camera again or stopping adjustment of the focal length of the camera according to the determination result received by the mobile device.