Watermarking Technique For Copyright Protection Research Articles

Watermarking technique for copyright protection of digital images using coupled differential equations

Watermarking technique for copyright protection of digital images using coupled differential equations

A blind proposed 3D mesh watermarking technique for copyright protection

ABSTRACTWatermarking provides an efficient mechanism for copyright protection of digital media by embedding information in the object to identify the owner. This paper proposed a watermarking technique that can successfully embed a grey-scale image in a 3D mesh object. In our proposed technique, each three vertices of the 3D object can hide one pixel from the secret image. The experimental results showed that the proposed technique has better visual quality on both the watermarked object and the extracted secret image.

Image watermarking based on inter-tree coefficients differencing in paired wavelet-packets tree constructions

Recently, image watermarking has been used as a tremendous mean for copyright protection of images and multimedia as well. This work presents an image watermarking technique for copyright protection of grayscale images, and is based on the exploitation of the properties of the wavelet packet decomposition (WPD). Here, the input image is applied to WPD, then, modified trees are constructed in such a manner to gather WPD coefficients sharing the same spatial locations at different frequency subbands. The obtained new trees are reorganized in pairs and a differencing step, between the inter-tree coefficients, is performed. The result is compared to a bi-level threshold. At the embedding stage, few locations are modified while most of the locations are left unchanged. To improve the technique security, a content-dependent watermark is implemented and the threshold is made adaptive to the host under consideration. Simulation results have shown superior output watermarking quality with a PSNR > 48 dB as well as high robustness against a wide variety of attacks including moderate-to-severe image compression, filtering, noise addition and enhancement manipulations. Moreover, the technique has demonstrated a low computational cost due to the used approach in selecting the reorganized WPD coefficients.

Hybrid domain watermarking technique for copyright protection of images using speech watermarks

When digital images are shared over an open access network such as the internet, facebook, WhatsApp, and other social media, then the security of these images are required. The digital watermarking is one approach for the security of images (e.g. copyright protection, ownership authentication). In most of the watermarking approaches, secret information such as owner binary logos and texts are used for protection of images. These days, biometric watermarks such as human speech signals are preferred for protection of images. In this paper, a watermarking technique based on various signal processing transforms is proposed and implemented for the security of image using human speech signal. In this technique, the first discrete cosine transform (DCT) and then singular value decomposition (SVD) are applied on the watermark speech signal to get its hybrid coefficients which are inserted into hybrid coefficients of the cover image to get a watermarked image. These hybrid coefficients of cover image are first generated using discrete wavelet transform (DWT) and then fast discrete curvelet transform (FDCuT) is applied on it. The performance of techniques is tested for standard speech database such as TIMIT in terms of imperceptibility, robustness and payload capacity. The experimental results and comparison show that the proposed watermarking technique performs better than the existing watermarking techniques available in the literature. This technique may also be used for security of speech signal against spoof attack.

An Improved Watermarking Technique for Copyright Protection Based on Tchebichef Moments

Watermarking technique is a method to protect ownership of digital multimedia. Most existing watermarking techniques achieve a good level of imperceptibility and robustness. The challenges to achieve higher invisibility and resistance with lower computational time motivate researchers to work on new watermarking schemes. Robustness against noise attacks and JPEG2000 compression needs to be improved to acquire a better resistance capability of the watermark. In this paper, we present a block-based Tchebichef watermarking technique for protecting copyrights. In this technique, the host image is first divided into non-overlapping blocks and Tchebichef moments are calculated for each block. The watermarks are embedded into the blocks with lower visual entropies. The watermark image is scrambled by Arnold transform before embedding into the Tchebichef moments of the selected image blocks. The proposed watermarking scheme was tested under noise additions, filtering, cropping and compressing attacks. Our scheme was verified and compared to the existing watermarking techniques under image geometric and processing attacks. Furthermore, the proposed scheme demonstrated a superior performance in robustness under noise attacks and JPEG2000.

Digital Audio Watermarking using Frequency Masking Technique

There is a need of an effective watermarking technique for copyright protection and authentication of intellectual Property [12]. In this work we propose a digital watermarking technique which makes use of simultaneous frequency masking to hide the watermark information into host. The algorithm is based on Psychoacoustic Auditory Model and Spread Spectrum theory [2]. It generates a watermark signal using spread spectrum theory and embeds it into the signal by measuring the masking threshold using Modified Psychoacoustic Auditory model and using dct transform. Since the watermark is shaped to lie below the masking threshold, the difference between the original and the watermarked copy is imperceptible. Recovery of the watermark is performed without the knowledge of the original signal. The software system is implemented using MATLAB and the characteristics studied. General Terms Digital Watermarking, Audio Watermarking, Masking.

An Image Transmission System Utilizing Chaos-Based Watermarking Technique

In this paper, an image transmission system utilizing chaos-based watermarking technique for copyright protection of the image transmission system is demonstrated experimentally. This system assures when pirated image is found, the illegal user can be traced. The users message after chaotic encryption as watermark can be embedded into image. Experimental results show our system which is used for a web-based image transmission is effective and robust. Especially, users message can also be extracted from the watermark image under diverse attacks such as some image-processing operations and Joint Photographic Experts Group (JPEG) compression.

스테레오 영상의 소유권 보호를 위한 워터마킹 기법

본 논문에서는 스테레오 영상의 소유권 보호를 위한 워터마킹 기법을 제안한다. 제안한 기법은 스테레오 정합을 통해서 얻어진 변위 맵에서 폐색 영역에 해당하면서 적절한 주파수 계수를 갖는 영역에 워터마크를 삽입한다. 주파수 변환 도구로는 이산 웨이블릿 변환을 사용한다. 제안한 알고리즘은 스테레오 정합, 워터마크 재배열, 워터마크 위치 선정, 그리고 워터마크 삽입 및 추출로 구성된다. 미들버리에서 제공하는 4가지 실험 영상에 대해서 실험을 수행하였다. 4 가지 영상에 대해서 워터마크를 다양한 강인성을 갖도록 삽입하였고, 이들에 대해서 다양한 공격에 대한 워터마크 추출율을 검출하였다. 또한 3D TV에서 다양한 워터마크 삽입 영상을 시각적으로 분석하였다. In this paper, we propose a new watermarking technique for copyright protection of stereo image. The proposed technique embeds watermark to the region which corresponds to occlusion of the disparity map to be extracted by the proposed stereo matching and the frequency coefficient with the appropriate value. We use discrete wavelet transform for frequency transform tool. The proposed algorithm consists of stereo matching, watermark rearrange, mark space selection, and watermark embedding/extracting. We tested the experiment about 4 stereo images which are from Middlebury site. We embedded the watermark to 4 stereo images and extracted it from the images after attacks. We also visually analyzed the watermark embedding images in 3D TV environment.

An improved SVD-based watermarking technique for copyright protection

The drawbacks of SVD-based image watermarking are false positive, robust and transparency. The former can be overcome by embedding the principal components of the watermark into the host image, the latter is dependent on how much the quantity (i.e., scaling factor) of the principal components is embedded. For the existing methods, the scaling factor is a fixed value; actually, it is image-dependent. Different watermarks need the different scaling factors, although they are embedded in the same host image. In this paper, two methods are proposed to improve the reliability and robustness. To improve the reliability, for the first method, the principal components of the watermark are embedded into the host image in discrete cosine transform (DCT); and for the second method, those are embedded into the host image in discrete wavelets transform (DWT). To improve the robustness, the particle swarm optimization (PSO) is used for finding the suitable scaling factors. The experimental results demonstrate that the performance of the proposed methods outperforms than those of the existing methods.

A Semi-blind Digital Watermarking Scheme Based on the Triplet of Significant Wavelet Coefficients

We proposed a semi-blind digital image watermarking technique for copyright protection. The proposed algorithm embedded a binary sequence watermark into significant wavelet coefficients by using a quantization method. The main idea of the quantization method was to quantize a middle coefficient of the triplet of a significant wavelet coefficient according to the watermark's value. Unlike an existing algorithm, which used a random location table to find a coefficient in which the watermark bit will be embedded: the proposed algorithm used quad-tree decomposition to find a significant wavelet coefficient for embedding. For watermark detection, an original host image was not required. Thanks to the usage of significant wavelet coefficients, the proposed algorithm improved the correlation value, up to 0.43, in comparison with the existing algorithm.

제거 가능한 로고 워터마킹 기법

In this paper, we propose a removable logo watermarking technique for copyright protection of digital image. Then, visible logo is inserted into digital image to protect copyright, and the information removed by the logo is embedded by a new quantization watermarking. In a legal usage, the image can be reconstructed without logo after watermarking detection process. Experiment results show that the proposed method maintains high image quality in both watermarked images and reconstructed images, and is practical and effective in protection of image copyright.

DCT-domain watermarking techniques for still images: detector performance analysis and a new structure

In this paper, a spread-spectrum-like discrete cosine transform (DCT) domain watermarking technique for copyright protection of still digital images is analyzed. The DCT is applied in blocks of 8x8 pixels, as in the JPEG algorithm. The watermark can encode information to track illegal misuses. For flexibility purposes, the original image is not necessary during the ownership verification process, so it must be modeled by noise. Two tests are involved in the ownership verification stage: watermark decoding, in which the message carried by the watermark is extracted, and watermark detection, which decides whether a given image contains a watermark generated with a certain key. We apply generalized Gaussian distributions to statistically model the DCT coefficients of the original image and show how the resulting detector structures lead to considerable improvements in performance with respect to the correlation receiver, which has been widely considered in the literature and makes use of the Gaussian noise assumption. As a result of our work, analytical expressions for performance measures, such as the probability of errors in watermark decoding and the probabilities of false alarms and of detection in watermark detection, are derived and contrasted with experimental results.

An adaptive digital image watermarking technique for copyright protection

An adaptive digital image watermarking technique is proposed. The proposed method exploits the sensitivity of human eyes to adaptively embed a visually recognizable watermark in an image without affecting the perceptual quality of the underlying host image. In addition, the watermark will still be present if some lossy image processing operations such as low-pass filtering, median filtering, resampling, requantization, and lossy JPEG image compression are applied to the watermarked image. Experimental results show the effectiveness of the proposed watermarking method.