Research On Data Hiding Algorithm Based On Absolute Moment Block Truncation Coding

Absolute Moment Block Truncation Coding(AMBTC)is widely used for real-time transmission of digital compressed images on the Internet due to its fast encoding,decoding,low computational complexity,and high compression rate.Therefore,Data Hiding(DH)technology with AMBTC image as the carrier has attracted widespread attention and research.However,the data hiding related algorithm of digital image as a carrier has problems such as low image quality,less embedded capacity and low security when applied to AMBTC images.Therefore,according to the data structure characteristics of AMBTC image,this paper proposes three data hiding algorithms based on absolute moment block truncation coding.The main research work of this paper is as follows:(1)Aiming at the problem that most of the current AMBTC data hiding algorithms operate on the high and low quantization levels in AMBTC coding,which leads to the degradation of image quality,an AMBTC data hiding algorithm based on modulo-2 operation is proposed in this paper.First,the algorithm uses AMBTC to encode the image blocks in the cover image according to the idea of image blocking to obtain a triple consisting of high and low quantization levels and bitmaps.Then,according to the threshold,the image blocks are divided into smooth types or complex types,and different embedding strategies are adopted to reduce the distortion of the stego image.For smooth image block type,the secret data and the four most significant bits plane of the two quantization levels are calculated using modulo-2 operation to replace the bitmap in order to improve the security of data transmission.Moreover,(3,2)Hamming code is used to embed the two additional secret bits in the three significant bits planes of the two quantization levels.For complex types,the order of the two quantization levels is exchanged and the bitmap is inverted to embed the secret data losslessly.This algorithm shows good performance on the standard image library,realizes high embedding capacity,and ensures good visual quality of stego image.(2)Aiming at the problem of the low embedding capacity of AMBTC reversible data hiding,an AMBTC reversible data hiding algorithm based on residual histogram is proposed.First,the algorithm improves the selection of the reference value in the residual histogram.By using the central reference value calculation for the high and low quantization levels in AMBTC coding,the residual histogram data is more concentrated,and the frequency of peaks in the histogram is increased.Thereby increasing the embedding capacity.Secondly,the mean values of the high and low quantization levels are introduced as intermediate values,and the difference between the mean and high quantization levels is calculated to construct a difference image,which is combined with the histogram algorithm to embed secret data.Finally,in combination with the encoding characteristics of high and low quantization levels in AMBTC coding,swapping the order of high and low quantization levels and flipping the bitmap,the lossless embedding strategy does not change the image quality.The algorithm can recover the AMBTC image completely reversibly after extracting the secret data and maintains a high embedding capacity.(3)Aiming at the current low security of single image AMBTC reversible data hiding,a dual image based AMBTC reversible data hiding algorithm is proposed in this paper.First,the algorithm uses the high correlation of high and low quantization levels in AMBTC coding to combine the high and low quantization levels in all image blocks into high and low quantization level images.Secondly,the secret data is embedded into the high and low quantization level images using a movable pixel coordinate strategy.Finally,the image block is divided into a smooth type or a complex type according to the threshold value,and the secret data is embedded into the bitmap of the smooth type image block through an exclusive OR operation,thereby enhancing the security of the data.The algorithm embeds secret dara into the cover image to obtain two stego images.Compared with single image data hiding,the secret data can only be extracted correctly when both stego images are available in the dual image data hiding,which improves the security of the data.In addition,the dual image data hiding combined with the high correlation of high and low quantization levels in AMBTC coding reduces the gap between the stego image and the cover image,and ensures good visual quality of image.