Reversible Data Hiding Algorithm For Image Enhancement

The traditional information hiding technology may cause permanent distortion of the source data, and lead to lose their original use value, for some applications need to be used again and need a lot of space to store the original information. The reversible techniques can fully restore the source data after the hidden data being correctly extracted, and it not requires additional space to store the original data. Therefore, the reversible information hiding technology has a broad application prospect in some occasions with higher requirements, such as military image, remote sensing image processing, medical diagnosis and legal certification, and other fields.Reversible information hiding algorithm commonly used peak signal-to-noise ratio to evaluate the image quality, but the evaluation criteria exist some defects. To improve image quality obviously is more important than to keep the peak signal-to-noise ratio higher for weak brightness images. This paper takes simple grayscale images as research object, and takes reversible information hiding based on histogram modification as research content.A new reversible data hiding strategy is proposed for low embedding rate. To increase the information hiding rate, the highest bins at both sides of the median point in image histogram are chosen to be split for data embedding, respectively. Multiple pairs of histogram bins are chosen for data embedding and the pair of the median point is chosen at last. The median point can be located directly after embedding, so that reversible data embedding and image recovered could be achieved, in addition, there is no need for the replacement of the least significant bit which requires a simple computation.Then, from the point of view of practical application, the reversible information hiding technology is applied to the satellite remote sensing image. For the influence by environmental factors lead to image contrast decreased on Satellite remote sensing Images, and the existing reversible information hiding algorithm has low capacity. A new reversible data hiding algorithm is proposed for image contrast enhancement and secure transmission. In order to improve the embedding rate, the proposed algorithm change the way of embedding, and gradually increase the contrast of satellite remote sensing images when the information is embedded in the process. Experimental results show that the proposed algorithm can achieve high pure payload embedding capacity and image contrast enhancement while comparing with typical reversible data hiding algorithm.