Reversible Watermark Using the Difference Expansion of a Generalized Integer Transform

2004 ◽  
Vol 13 (8) ◽  
pp. 1147-1156 ◽  
Author(s):  
A.M. Alattar
Keyword(s):  
Integer Transform ◽  
Difference Expansion ◽  
The Difference ◽  
Generalized Integer Transform ◽  
Reversible Watermark

scholarly journals An Improved Integer Transform Combining with an Irregular Block Partition

Symmetry ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 49 ◽  
Author(s):  
Shaowei Weng ◽  
Yi Chen ◽  
Wien Hong ◽  
Jeng-Shyang Pan ◽  
Chin-Chen Chang ◽  
...  
Keyword(s):  
Mean Value ◽  
Invariance Property ◽  
Integer Transform ◽  
Image Block ◽  
Block Partition ◽  
Local Complexity ◽  
The Difference ◽  
Embedding Performance ◽  
Partition Method ◽  
Embedding Distortion

After conducting deep research on all existing reversible data hiding (RDH) methods based on Alattar’s integer transform, we discover that the frequently-used method in obtaining the difference value list of an image block may lead to high embedding distortion. To this end, we propose an improved Alattar’s transform-based-RDH-method. Firstly, the irregular block partition method which makes full use of high correlation between two neighboring pixels is proposed to increase the embedding performance. Specifically, each image block is composed of a center pixel and several pixels surrounding this center pixel. Thus, the difference value list is created by using the center pixel to predict each pixel surrounding it. Since the center pixel is highly related to each pixel surrounding it, a sharp difference value histogram is generated. Secondly, the mean value of an image block in Alattar’s integer transform has embedding invariance property, and therefore, it can be used for increasing the estimation performance of a block’s local complexity. Finally, two-layer embedding is combined into our scheme in order to optimize the embedding performance. Experimental results show that our method is effective.

Reversible Authentication Scheme of Images Based on Lifting Wavelet Transform

2013 ◽  
Vol 278-280 ◽  
pp. 1379-1382 ◽  
Author(s):  
Yan Yan ◽  
Yuan Sun ◽  
Hui Qin Wang ◽  
Ying Lin ◽  
Hai Yan Chen
Keyword(s):  
Wavelet Transform ◽  
Expansion Method ◽  
Image Authentication ◽  
Reversible Watermarking ◽  
Lifting Wavelet Transform ◽  
Difference Expansion ◽  
Quad Tree ◽  
Good Ability ◽  
Lifting Wavelet ◽  
The Difference

A new reversible watermarking algorithm for image authentication, which embeds authentication information into the sub-band coefficients after lifting wavelet transform by using the difference expansion method, is proposed in this paper. Block map, after quad-tree decomposition, is used to represent the whole characteristic of image content and embed it into the original image as watermark information. Experiments results show that the proposed scheme can restore the image reversibly and has good ability to detect and locate vicious tamper.

Efficient Generalized Integer Transform for Reversible Watermarking

2010 ◽  
Vol 17 (6) ◽  
pp. 567-570 ◽  
Author(s):  
Xiang Wang ◽  
Xiaolong Li ◽  
Bin Yang ◽  
Zongming Guo
Keyword(s):  
Reversible Watermarking ◽  
Integer Transform ◽  
Generalized Integer Transform

scholarly journals An improved reversible image watermarking algorithm based on difference expansion

2017 ◽  
Vol 13 (1) ◽  
pp. 155014771668657 ◽  
Author(s):  
Zhengwei Zhang ◽  
Lifa Wu ◽  
Yunyang Yan ◽  
Shaozhang Xiao ◽  
He Sun
Keyword(s):  
Image Watermarking ◽  
Visual Quality ◽  
Information Value ◽  
Original Image ◽  
Difference Expansion ◽  
Image Block ◽  
The Difference ◽  
Carrier Image ◽  
Reversible Image Watermarking ◽  
Embedding Rate

To improve the visual quality and the embedding rate of the existing reversible image watermarking algorithm, an improved reversible image watermarking algorithm based on difference expansion is proposed. First, the watermark information is divided into groups, and the information value of each group is calculated. The watermark group number and the corresponding carrier image block number are mapped, and the corresponding coefficient position of each corresponding carrier block is identified according to the value of the watermark information in each group. Second, the identified location map is compressed and embedded in the original image through the difference expansion. Through circular searching the suitable pixel position, the embedding rate can be effectively improved without sacrificing any visual quality. The experimental results show that the proposed algorithm not only has high embedding rate but also has a high visual quality and can achieve full recovery of the original image. Compared with other algorithms, the algorithm has certain advantages.

The Origin of the Moon

1962 ◽  
Vol 14 ◽  
pp. 149-155 ◽  
Author(s):  
E. L. Ruskol
Keyword(s):  
Chemical Composition ◽  
Solar System ◽  
The Moon ◽  
The Earth ◽  
The Difference ◽  
Origin Of The Moon

The difference between average densities of the Moon and Earth was interpreted in the preceding report by Professor H. Urey as indicating a difference in their chemical composition. Therefore, Urey assumes the Moon's formation to have taken place far away from the Earth, under conditions differing substantially from the conditions of Earth's formation. In such a case, the Earth should have captured the Moon. As is admitted by Professor Urey himself, such a capture is a very improbable event. In addition, an assumption that the “lunar” dimensions were representative of protoplanetary bodies in the entire solar system encounters great difficulties.

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