Image characteristic extraction method, device thereof, image copy detection method and system thereof

Abstract

The invention discloses an image characteristic extraction method, a device thereof, an image copy detection method and a system thereof. The image characteristic extraction method includes the following steps of: zooming an extracted image to a K-dimensional gray matrix; for each point position in the matrix, combined with position and a gray value of other pixels, calculating a characteristic value, and forming two K-dimensional image characteristic matrices; and respectively selecting two points with maximum values in the two characteristic matrices as characteristic points, forming three line segments representing image characteristics with the above four characteristic points, and obtaining characteristics of the extracted image. Since when extracting the image characteristics, it is independent of color information of the image and is not related with an image size, and there is no extra overhead when carrying out characteristic extraction on a large size color image; the characteristic line segments are employed in an image characteristic extraction process, as long as image structure is not significantly changed, the image characteristic line segments are relatively stable, high detection precision is provided, and functions of detecting an attack type and analyzing attack intensity are provided.

Description

technical field [0001] The invention relates to the technical field of image analysis of general image data, in particular to the technical field of image copy detection. Background technique [0002] Copy detection technology based on image content, referred to as image copy detection, as an important digital image management technology, has become a hot research topic. The task of image copy detection is: given the detected image, search in the image database to detect whether there is an image with similar or identical content; if there is, the detected image is a copy image. [0003] The copied image is obtained through various copy attacks on the source image, including cropping, rotating, adding subtitles, noise, etc. Although copy attacks have been performed, the content of the copied image is consistent with the original image, and the image copy detection technology needs to be able to deal with these copy attacks. [0004] Digital image has become a widely used i...

AI Technical Summary

Problems solved by technology

[0005] Today, more and more individuals and organizations are disseminating self-made images on the Internet for different purposes, which has brought increasingly serious challenges to digital image content management, copyright protection, and especially bad image filtering.

[0006] The key to the current image copy detection technology scheme lies in the extraction method of image features. In terms of feature extraction, most of them use the extraction of color features, texture features and transformation domain features as the relevant basis, and the focus of these algorithms is often on the global features of the image. Color, brightness and contrast are sensitive to changes, and cannot effectively deal with geometric distortion attacks

[0007] In recent years, researchers have proposed a method based on local features, which represents an image as a collection of several local blocks, and detects related images by querying the blocks that make up the target image; because this feature is somewhat ruthless to common attack methods Stickiness, so it is widely used, but the computational complexity of this feature is high, which cannot meet the needs of real-time applications under large-scale data

[0008] Therefore, in the field of image copy detection, there is currently a lack of copy detection methods that meet real-time requirements and can resist noise attacks and geometric attacks.

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