An Image Information Hiding Algorithm Based on Three-Coefficient Block Encoding in DCT Domain

This study presented a new algorithm for hiding information in an carrier image. It hides information by using the numerical value relation of three neighboring DCT coefficients with Zig-Zag order of block image. Firstly, each block of image is transformed by DCT. Then the DCT coefficient matrix is scanned by Zig-Zag scanning order to ensure the continuity of the neighboring coefficients. And then through modifying the numerical value relation of three Zig-Zag neighboring DCT coefficients, the three corresponding secret bits are embedded in. In order to improve its performance, the algorithm also employs redundant encoding, and scrambling techniques etc. The experiments show that the algorithm can guarantee a better quality of stego-image, and it is robust to general image processing operations.