A method for measuring the size of rectangular transparent plastic bags

Abstract

The invention discloses a method for measuring the size of a rectangular transparent plastic bag. The steps include: continuously photographing the plastic bag to be tested; performing grayscale transformation on the image to obtain a grayscale image, and then performing Gaussian filtering on the grayscale image; Edge detection is performed on the final grayscale image, and then the Hough transform is performed to extract the straight line satisfying the Hough transform; the end points of all straight lines are obtained and an end point set is formed; the convex hull of the end point set is obtained by using the distribution of each end point in the end point set , and then calculate the minimum covering rectangle for the convex hull; calculate the number of pixels occupied by the length and width of the minimum covering rectangle, and then use the method of least squares to establish the functional relationship between pixels and millimeters; according to the functional relationship Calculate the length and width of the smallest rectangle of each photo, and then take the average to obtain the final length and width of the plastic bag. The size measurement method has a small amount of calculation, is easy to implement, meets the real-time requirements of industrial sites, and has high engineering application value.

Description

technical field [0001] The invention relates to a size measuring method, in particular to a size measuring method for rectangular transparent plastic bags. Background technique [0002] Dimensional measurement is an important link in modern manufacturing and a key technical issue in product manufacturing. The traditional measurement method is to use mechanical measuring tools and measure manually. This method is seriously affected by measuring tools and human factors, and the measurement error is large. Therefore, the traditional contact manual measurement method is gradually replaced by non-contact measurement. At present, the research direction of non-contact measurement is mainly concentrated in the two directions of laser measurement technology and computer vision technology. Advantages, no special requirements on the environment, and the price is lower than laser scanning, so it has great development prospects in the field of measurement. In most mechanical parts, s...

AI Technical Summary

Problems solved by technology

[0003] However, the Hough transform is prone to false straight lines, resulting in low detection accuracy

At the same time, due to the serious diffuse reflection problem when taking pictures of transparent objects such as plastic bags, there are many problems when Hough transform solves the boundary line of plastic bags

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