abstract
With the rapid development of modern science and technology, in order to collect, process and automate micro-images quickly and accurately, higher requirements are put forward for digital automation, and one of the key problems is autofocus. Due to the perfection and gradual maturity of digital image processing theory, autofocus system has gradually changed from autofocus based on optical system to autofocus based on digital image processing. In order to improve the performance of the equipment, this paper studies the autofocus technology, including the theory and method of automatic convergence and the evaluation function of algorithm convergence.
In this paper, the theory and method of automatic focusing based on image processing are studied, and a convergence-based ranking gradient and evaluation function are proposed. This function ranks the gradients as before and calculates the gradient sum as the evaluation function of focusing. The experiment has a good evaluation performance on the size change of the target within a certain function range to reduce the sharpness of noise on the evaluation curve. It is compared with the proposed focusing threshold algorithm based on statistical gradient. The experimental results show that this method has high accuracy under multi-frame dynamic threshold and multi-directional gradient focusing.
It is quite necessary to judge the convergence of images before HDTV. A distributed gradient algorithm based on edge contrast judgment of single frame image is proposed. Experiments show that the algorithm has good judgment performance for equipment images. Based on the clarity of the current image, the autofocus error is reduced.
This paper designs a convergence experiment system based on pc. The accuracy and reliability of the autofocus technology in this study are proved by the experiments of simulating real targets and targets.
Keywords: digital camera; Auto focus; Evaluation function; Convergence experimental system (note that English keywords should be separated by semicolons, which is the format requirement of the paper)