Research On Autofocus Judgment Of Series Digital Images Based On DSP

Autofocus technology is extensive used in Digital Camera, Digital Video, Endoscopic area. DSP is usually used in Real-time system , and can provide high performance of Speed , Precision and Power saving. We compared 5 judgments which are common used in autofocus area, and choose judgments based on Laplacian, SPSMD and DWT as better performance judgments. Then we do some deeper research on those three judgments by comparing their performances in different image information, different image contrast, and random noise. At last we choose the judgment based on DWT as the best performance in different environments,and transplant the algorithm on the TMS320C6711 DSP platform. After hard work of developing, debugging and optimizing, the result of the verify test shows we achieve the speed that we need only 7.5ms to do 2-D DWT process on a 256 by 256 pixels digital image and the focus position can be definitely found.