Reversible watermarking using optional prediction error histogram modification
To reduce the distortion of high payload watermarking scheme, a reversible watermarking based on optional prediction-error histogram modification is proposed to improve the watermarked image fidelity at high embedding rate. By considering the pixel compensation during the multiple layer embedding, an optional predictor is designed to generate the most appropriate prediction error histogram, which results in less distortions at the same embedding rate. Unlike other histogram based schemes, the generated prediction error histogram can be tuned through the selection of threshold for each layer to strike the balance between capacity and pixel compensation. Compared with the other schemes, the proposed scheme introduces less distortion and obtains high image quality for the high embedding rate. The experiments on the standard and military images verify the effectiveness of the proposed scheme.
reversible watermarking prediction error optional histogram shifting