为了提供较大的秘密信息嵌入量和保持良好的载密图像质量,依据人眼对变换剧烈及较暗区域均不敏感的视觉特点,提出了一种基于小波对比度和最低比特位替换(LSB)的图像密写方法.该方法先将载体图像分成固定大小的小块,对每一小块进行小波分解后计算小波对比度.然后,根据该块小波对比度绝对值之和确定该块可以嵌入的位平面层数.最后,采用LSB密写技术逐层嵌入秘密信息.实验结果表明,该密写方法能嵌入较多的信息和保持良好的载密图像质量,并且可直接从载密图像中提取秘密信息.-In order to provide larger capacity of the hidden secret data and to maintain a good visual quality of stego-image,in accordance with the visual property that human eyes are insensitive to edged area and dark area,a novel steganographic method based on wavelet contrast and Least-Significant-Bit(LSB)replacement is presented.First,an image is divided into blocks,and every block is decomposed into one-level wavelet to obtain the wavelet contrast.Then,the number of bit-plane embedded is decided with the s...