The principle of digital watermark is the method of adding digital watermark in the frequency domain. The digital watermark hides the watermark in digital media, such as image, voice, video, etc., so as to realize the...The principle of digital watermark is the method of adding digital watermark in the frequency domain. The digital watermark hides the watermark in digital media, such as image, voice, video, etc., so as to realize the functions of copyright protection, and identity recognition. DCT for Discrete Cosine Transform is used to transform the image pixel value and the frequency domain coefficient matrix to realize the embedding and extracting of the blind watermark in the paper. After success, the image is attacked by white noise and Gaussian low-pass filtering. The result shows that the watermark signal embedded based on the DCT algorithm is relatively robust, and can effectively resist some attack methods that use signal distortion to destroy the watermark, and has good robustness and imperceptibility.展开更多
A new asymmetric watermarking scheme is proposed in this letter. In the proposed scheme, a secret real fractional DCT-I transform and a primitive watermark are employed to generate an asymmetric watermark. The secret ...A new asymmetric watermarking scheme is proposed in this letter. In the proposed scheme, a secret real fractional DCT-I transform and a primitive watermark are employed to generate an asymmetric watermark. The secret watermark for em-bedding is derived from the primitive watermark, and is embedded in the large fractional DCT-I transformation coefficients of a cover signal. The asymmetric detection procedure is performed using a correlation test. Simulation results showed that the asymmetric detection is reliable, and that the scheme can provide minimum security.展开更多
In this paper, for color image copyright protection application, a new and blind color image watermarking algorithm based on quantitation method in three dimensional discrete cosine transform (3D-DCT) is proposed. Fir...In this paper, for color image copyright protection application, a new and blind color image watermarking algorithm based on quantitation method in three dimensional discrete cosine transform (3D-DCT) is proposed. Firstly, the original RGB color image is divided into non-overlapping blocks sized 8 × 8 × 3, and then performs 3D-DCT transform on each block. Secondly, embed a bit watermarking signal into each block’s 3D-DCT direct-current (DC) coefficient by quantization method. The results show that the proposed scheme has very good imperceptibility and robustness against the common image processing attacks. Compared with similar algorithm, the proposed scheme has better robustness performance for most attacks.展开更多
文摘The principle of digital watermark is the method of adding digital watermark in the frequency domain. The digital watermark hides the watermark in digital media, such as image, voice, video, etc., so as to realize the functions of copyright protection, and identity recognition. DCT for Discrete Cosine Transform is used to transform the image pixel value and the frequency domain coefficient matrix to realize the embedding and extracting of the blind watermark in the paper. After success, the image is attacked by white noise and Gaussian low-pass filtering. The result shows that the watermark signal embedded based on the DCT algorithm is relatively robust, and can effectively resist some attack methods that use signal distortion to destroy the watermark, and has good robustness and imperceptibility.
基金Project (Nos. 60372076 and 60272082) supported by the National Natural Science Foundation of China
文摘A new asymmetric watermarking scheme is proposed in this letter. In the proposed scheme, a secret real fractional DCT-I transform and a primitive watermark are employed to generate an asymmetric watermark. The secret watermark for em-bedding is derived from the primitive watermark, and is embedded in the large fractional DCT-I transformation coefficients of a cover signal. The asymmetric detection procedure is performed using a correlation test. Simulation results showed that the asymmetric detection is reliable, and that the scheme can provide minimum security.
文摘In this paper, for color image copyright protection application, a new and blind color image watermarking algorithm based on quantitation method in three dimensional discrete cosine transform (3D-DCT) is proposed. Firstly, the original RGB color image is divided into non-overlapping blocks sized 8 × 8 × 3, and then performs 3D-DCT transform on each block. Secondly, embed a bit watermarking signal into each block’s 3D-DCT direct-current (DC) coefficient by quantization method. The results show that the proposed scheme has very good imperceptibility and robustness against the common image processing attacks. Compared with similar algorithm, the proposed scheme has better robustness performance for most attacks.
基金国家自然科学基金(the National Natural Science Foundation of China under Grant No.60572048)湖北省教育厅自然科学基金(the Natural Science Foundation of DOE of Hubei Province, No.D200613003)
