Sobel operator-based extraction method of profile and detail composite characteristic vector used for representing fabric texture

Abstract

The invention belongs to the field of digital image processing and pattern identification, and in particular relates to a Sobel operator-based extraction method of a profile and detail composite characteristic vector used for representing fabric texture. The method comprises the following steps of: performing horizontal and vertical Sobel operator filtering processing on an original fabric image to acquire two corresponding filtering images; calculating a set of gray level statistics, which have a uniform mode and serve as two profile characteristics, of the two filtering images; simultaneously, calculating to obtain four extremal gray level statistics serving as four detail characteristics, from the two filtering images, according to a basic cycle period of the fabric texture and a traversing method, wherein the gray level statistics are consistent with that which is selected when the profile characteristic is calculated; and combining the two profile characteristics with the four detail characteristics to form the composite characteristic vector. In the composite characteristic vector, each characteristic has high complementarity; and the composite characteristic vector gives consideration to profile information and detail information of the texture and also to horizontal information and longitudinal information of the texture, and can fully describe characteristics of the fabric texture in detail.

Description

technical field [0001] The invention belongs to the field of digital image processing and pattern recognition, and in particular relates to a Sobel operator-based method for extracting feature vectors of a mixture of outline and detail for characterizing fabric texture. Background technique [0002] With the help of fabric texture characterization technology, the purposes of fabric texture parameter estimation, texture classification, fabric appearance evaluation, and defect detection can be realized. Any fabric texture contains two important information, namely general information and detail information. The overview information provides the overall rough structure and grayscale impression for human eyes or machine vision, while the detail information provides the local fine structure and grayscale impression. Therefore, in order to fully and meticulously characterize the texture structure and reflect the texture characteristics to the maximum extent, both the general appe...

AI Technical Summary

Problems solved by technology

The report did not consider the basic cycle length of the texture period as the basis for feature extraction, did not explain the selection method of the binarization threshold, and the single feature extracted only involved the number of border point pixels, and did not clearly define the meaning of the border points The distribution of boundary points in the image

[0007] The fabric texture characterization methods involved in the above-mentioned existing literature or patents are limited to the extraction of global features for the characterization of fabric texture information, and fail to take into account both the general appearance and detailed information of fabric texture, so they cannot comprehensively and meticulously characterize the essential characteristics of fabric texture

In addition, the main feature of the above-mentioned Sobel operator texture representation method is that after the texture image is filtered by the Sobel operator, a certain threshold must be selected to realize the binarization of the image

This has two main disadvantages: one is that it is difficult to select the optimal threshold for different textures; the other is that after the image is binarized, a large amount of grayscale transition information is lost, leaving only black and full White binary information, while the texture image to be processed usually has 256 gray levels

Therefore, the above processing method is cumbersome and the features extracted on this basis cannot achieve a more adequate and appropriate representation of the texture.

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