Then, according to the periodicity of the discrete fractional cosine transform and the cipher keys, the encrypted image can be decrypted successfully. 利用离散分数余弦变换的周期性和密钥,可以成功地解密出原始图像。
The original image is transformed by the discrete fractional cosine transform with a random row cipher key vector and a random column key vector successively. 利用随机产生的行向量和列向量的各分量作为密钥依次对原始图像相应的行和列进行离散分数余弦变换,仿真结果表明经过该方法加密后的图像具有很好的加密效果。