Detection method of metal stamped characters with point light source based on Mach band effect simulation

Abstract

The invention relates to a Mach band effect simulation method for detecting metal stamp characters with a point light source, which comprises the following steps: 1. Using an area array camera to take pictures of the metal stamp to be detected under a point light source to obtain a frame of input image data; 2. Inputting Perform preprocessing operations on image data; 3. Establish a self-seeking quotient simulation image based on the Mach band; 4. Use a mapping function to normalize the value range of the self-seeking quotient simulation image according to the integer or floating-point quantization form; 5. Input the normalized image into the text detector based on the deep neural network to obtain the text envelope area; 6. Perform perspective transformation on the text envelope area to solve the perspective transformation matrix; 7. Input the perspective transformed image into the optical character Recognize the network to obtain the recognition result of metal stamped characters; the invention uses point light sources to detect metal stamped characters, which reduces the complexity, limitation and scale of the detection device, and has high detection accuracy, high speed and low cost.

Description

Technical field: [0001] The invention relates to a text detection method, in particular to a point light source metal steel stamp text detection method simulated by the Mach band effect. Background technique: [0002] Steel stamps are usually stamped on the outer side of the box of metal parts (such as gearboxes) or on the nameplates on the sides of the motor and internal combustion engine housings. The stamped characters are either raised or depressed. In industrial production or other automation processes, When a metal part is to be used, its identity needs to be identified, that is, it is necessary to detect the text on the steel stamp on the side of the metal part shell. The current detection methods mainly include: [0003] Use a coaxial light source to create the highlight area of ​​the text baseline. Because this method has high requirements for light source debugging, it is usually used on mass production lines, but it has no practical significance for flexible conf...

AI Technical Summary

Problems solved by technology

[0006] For industrial light sources, Gaussian light and coaxial light mean that the equipment is bloated, the detection area is huge, and the footprint is large, which cannot be flexibly embedded in common compact environments

[0007] However, not using an ideal light source can lead to inconsistencies in the high-frequency features of uneven objects under the light source

An extreme example is that a point light source is an extreme form of unbalanced light sources. The current detection system is difficult to overcome the problems of inconsistent highlights, shadows, and high-frequency features produced by point light sources.

At the same time, the existing highly integrated industrial cameras with active light sources cannot be used normally in high-intensity exposure environments

[0008] Therefore, the existing equipment and methods cannot meet the diversity of visual inspection application scenarios

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