An Improved Steganographic Scheme Implemented on the Compression Domain of Image Using BTC and Histogram Modification.

An image steganographic scheme is proposed in this article. The proposed scheme is implemented on the compression domain of image by applying block-truncation-coding (BTC) and histogram modification. The secret data are hidden into the BTC compression codes of image by exchanging the positions of the reconstructed values and by modifying the histogram generated from of the bitmap. Simulation results show that the performance is obviously improved by the proposed scheme in terms of the pure hiding capacity and the visual quality of stego-BTC-compressed image as compared with the earlier works. The averaged degradation of image quality, based on the peak signal to noise ratio (PSNR) criterion, is about 1.73 dB when it is compared with the original BTC-compressed images. Moreover, the proposed scheme is a reversible image steganographic scheme. The original BTC-compressed image can be losslessly reconstructed at the receiver after extracting the secret data. Therefore, we conclude that the proposed scheme is a feasible image steganographic scheme.