A low-resolution touch screen image defect detection method based on sparse representation

Abstract

The invention discloses a low-resolution touch screen image defect detection method based on sparse representation. The method includes 1, extracting image features from a normal touch screen image training set to establish a dictionary D of normal samples; 2, performing optimization screening on the redundant dictionary D with noise features and selecting a sub-dictionary D' serving as a sparse-representation dictionary of training samples; 3, during defect detection, extracting the features of an image y to be detected, and figuring out the coefficient of the y represented through the D' in a linear manner by means of l1 norm minimization; 4, if the image y to be detected is a touch screen image without defects, allowing the coefficient represented through the D' in a linear manner to be sparse, otherwise, allowing the coefficient to be not sparse. According to the method, a redundant dictionary of over complete bases is established through the touch screen image without defects, elements in the dictionary are selected in an optimized manner to establish a redundant dictionary, and defect detection is performed on the touch screen image by means of the characteristics that the touch screen image without defects can be reconstructed through the dictionary sparse linearity but an image with defects cannot be reconstructed through the dictionary sparse linearity.

Description

technical field [0001] The invention relates to the technical field of touch screen image defect detection, in particular to a low-resolution touch screen image defect detection method based on sparse representation. Background technique [0002] With the rapid development of information technology and flat display technology, the global touch screen market is growing rapidly with an average annual growth rate of 47%. At the same time, the requirements for touch screen production process and quality control are becoming more and more stringent. How to realize real-time and accurate detection of surface defects in the touch screen production process, block defective touch screen products from entering the subsequent process, reduce production costs, improve product quality, and avoid heavy losses caused by the use of defective touch screens is the touch screen industry. One of the most important links in the production process. [0003] The development of computer vision te...

AI Technical Summary

Problems solved by technology

In the actual production process, the image captured by the line array CCD camera (Charge-coupled device) on the touch screen contains shading, and there are many types of touch screen defects, such as dirt, ink, hair, foreign matter, etc., plus lighting conditions , camera resolution and other issues have brought greater difficulty to the use of image processing methods for touch screen defect detection

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