DCT (discrete cosine transform)-based anti-geometric-attack zero-digital-watermarking method for medical image

Abstract

The invention relates to a DCT (discrete cosine transform)-based anti-geometric-attack zero-digital-watermarking method for a medical image, wherein the embedding of watermarks is firstly carried out, and the extracting of the watermarks is then carried out. The method comprises the following steps: (1) carrying out full-image DCT on an original medical image, and extracting a vector which can represent the important visual features of the original image from transformed coefficients; (2) obtaining a binary logic sequence through the Hash function by using the eigenvector and the watermarks to be embedded; (3) carrying out the full-image DCT on a medical image to be tested, and finding out a visual eigenvector of the image to be tested; and (4) extracting the watermarks by using the characteristics of the Hash function and the binary logic sequence which is obtained when the watermarks are embedded. Based on the DCT digital-watermarking technology, the method provided by the invention is fast for the embedding of the watermarks under the condition of not influencing on the quality of original medical images, has the characteristics of rapid calculating speed, high accuracy, good compatibility, strong attack resistance and the like, and has a high practical value in aspects, such as protection of patient privacy and the like.

Description

technical field [0001] The invention belongs to the field of multimedia signal processing, and relates to a medical image digital watermarking technology based on DCT transformation and image visual features, in particular to a medical image zero digital watermarking method based on DCT against geometric attack. Background technique [0002] At present, medical images account for 70% to 80% of the medical information in the whole hospital. The digital information management system plays an increasingly important role in the modern medical system. However, with the popularization and application of the network, its information security problems are gradually exposed. [0003] When medical images are transmitted remotely on the network, the personal information of patients recorded on the medical images is easily leaked. If the personal information is embedded in the medical image as a digital watermark, this problem can be better solved. This kind of watermark is called medic...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to provide a zero-digital watermarking method for medical images based on DCT anti-geometric attack. By organically combining the visual feature vector of medical images, encryption technology and the concept of a third party, it is not necessary to select the region of interest. This solves the problem of fast watermark embedding and extraction, and has ideal robustness and invisibility to protect the copyright of medical images and the confidentiality of patient information, effectively solving the concealment of patient information and the privacy of medical images. Sensitivity issues, while solving the problem of resisting geometric attacks and resisting conventional attacks in medical image applications

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