An Auto-Focus Algorithm of Fast Search Based on Combining Rough and Fine Adjustment

Abstract:

A coarse and fine combined fast search and auto-focusing algorithm was suggested in this paper. This method can automatically search and find the focal plane by evaluating the image definition. The Krisch operator based edge energy function was used as the big-step coarse focusing, and then the wavelet transform based image definition evaluation function, which is sensitivity to the variation in image definition, was used to realize the small-step fine focusing in a narrow range. The un-uniform sampling function of the focusing area selection used in this method greatly reduces the workload and the required time for the data processing. The experimental results indicate that this algorithm can satisfy the requirement of the optical measure equipment for the image focusing.

• Periodical: Advanced Materials Research (Volumes 468-471)
• Pages: 534-537
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.468-471.534
• Online since: February 2012
• Authors: Zhao Hua Lin, Xin Liu, Yu Liang Zhang, Shu Mei Zhang
• Keywords: Auto Focusing, Evaluation Function, Image Processing, Optical Measurement

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