An Optimized Spatial Data Hiding Scheme Combined with Convolutional Codes and Hilbert Scan

Abstract

Abstract. This paper presents a new watermarking scheme, which is combined with convolutional codes and Hilbert scan in spatial domain. Our method considerably improves the capacity of watermarks and the robustness of the system as well, compared with the present watermarking systems. Human Visual System (HVS) is applied adaptively in the embedding step. Watermarks are modulated by pseudo-random sequences for precise detection and security purposes. When convolutional code is employed, we adopt soft-decision Viterbi decoding algorithm to achieve lower bit error rate (BER). Our experiments show that choosing suitable convolutional codes can considerably alleviate the trade-off between the capacity and the robustness. This algorithm is also computationally simple so that the information can be extracted without the original image in real time in video watermarking.

Robust Spatial Data Hiding for Color Images

“…In extraction algorithm a simple method accumulating the energy of three channels is used. By this method, we can achieve the capacity much higher than that of scheme in [5]. Lots of experiments show that the watermarking scheme we present excel not only single color algorithm, but also luminance channel algorithm.…”

“…Lots of experiment result proves that propose blind watermarking algorithm in the paper is able to hide 512 bits without error. Du [5] mainly studied four kinds of convolutional code with different constraint lengths by comparing their performance on BER with that of the uncoded scheme in single channel. Combined convulutional code with proposed algorithm, the capacity can be improved again.…”

“…To maximize the admissible amplitude of the unperceivable information embedded, we use the HVS model in [5] and calculate the JND mask of each color channel directly in the spatial domain. This algorithm contains 3 aspects: texture and edge analysis, edge separation and reclassification, luminance sensitivity analysis.…”

“…Previous researches were mostly focused on grayscale image watermarking. For color images, researchers usually embed information in luminance channel [2,3], or in a single color channel [4,5]. Alternative approaches to color image watermarking have been advanced by Fleet and Heeger [6], who suggest embedding the watermark into the yellow-blue channel of the opponent-color representation of color images.…”

A High Capacity Information Hiding Algorithm in Color Image

“…So it is possible that the algorithm make the information to embed by reducing the image's quality. Now information hiding algorithm based on spatial domain to color image generally embedded watermarking into Y component (bright channel) [4] of YCbCr pattern space or single color channel [5][6][7]. It can select the different channel according to the different needs.…”