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The purpose of this paper is to show how digital watermarking can be applied to assist and improve cryptography‐based digital rights management (DRM) systems by allowing the protection of content beyond the domain protected by the DRM system.

Digital watermarking is a passive technology, not allowing the active prevention of copyright violations. But it allows the irreversible linking of information with multimedia data, ensuring that an embedded watermark can be retrieved even after analogue copies. Therefore watermarking can be used where DRM fails: whenever content needs to be moved out of the protected DRM domain, e.g. when playing back content via analogue output channels it can mark the content with information that would help to identify its origin if it is used for copyright violations. The remaining challenge now is to find the marked content within the channels regularly used for copyright violations. The paper therefore introduces a concept for scanning file sharing networks for marked content.

The vast number of files present in the file sharing networks prohibits every approach based on completely scanning and analysing each file. Therefore concepts for filtered search queries where only potentially watermarked files are downloaded are discussed.

The paper shows how watermarking can be applied as a technology to allow active content protection beyond the limitations of current DRM systems.

The purpose of this paper is to present an imperceptible and robust watermarking algorithm with high embedding capacity for digital images based on discrete wavelet transform (DWT) domain.

First, the watermark image is scrambled using chaotic sequence and mapped to avoid the block effect after embedding watermark into the host image. Then, the scrambled watermark is inserted in LH₂ and HL₂ sub‐bands of the DWT of the host image to provide a good tradeoff between the transparency and the robustness of watermarks.

This paper presents experimental results and compares the results to other methods. It can be seen from the comparison that this method can obtain a better performance in many cases.

One of the main differences of this technique, compared to other wavelet watermarking techniques, is in the selection of the wavelet coefficients of the host image. When performing second level of the DWT, most methods in the current literature select the approximation sub‐band (LL₂) to insert the watermark. The technique presented in this paper decomposes the image using DWT twice, and then obtains the significant coefficients (LH₂ and HL₂ sub‐bands) of the host image to insert the watermark.

The technique for hiding confidential data in specific digital media by enhancing the graphical contents is known as watermarking. The dissemination of information over a secure channel is essential for multimedia applications. The purpose of this study is to develop a secure communication approach for OFDM system.

This paper exploits a secure communication in the orthogonal frequency division multiplexing (OFDM) system using wavelet-based video watermarking technique. In this work, the Chronological-MS algorithm is used for securing the data communication in the OFDM system. Here, the secret message is embedded in video frames using wavelet transform for hiding sensitive information and the hidden information is transmitted over the OFDM system. The Chronological-MS algorithm is used for selecting the optimal regions in the video for embedding secret message. In embedding phase, wavelet coefficients are obtained by applying wavelet transform on the frame for embedding the secret message. Meanwhile, in extraction phase, the inverse wavelet transform is applied to extract the secret message.

Considering number of frames, the maximum Peak signal-to-noise ratio (PSNR) value is attained by proposed Wavelet + Chronological MS method for Video 2 with value 73.643 dB, respectively. Meanwhile, the minimum mean squared error (MSE) attained by the proposed Wavelet + Chronological MS method is when considering number of frames with MSE values as 0.001 for both Videos 1 and 2. The minimum bit error rate (BER) value is attained by the proposed method with value 0.00009 considering random noise with Video 1. Thus, the proposed Wavelet + Chronological MS have shown better results than the existing techniques.

This work proposes a wavelet-based watermarking method using Chronological-MS, for initiating secured communication over an OFDM. One of the main advantages of wavelets is that they offer a simultaneous localization in time and frequency domain. Hence, the proposed method offers the highly secured data transmission over the OFDM.

Watermarking technique is one of the significant methods in which carrier signal hides digital information in the form of watermark to prevent the authenticity of the stakeholders by manipulating different coefficients as watermark in time and frequency domain to sustain trade-off in performance parameters. One challenging component among others is to maintain the robustness, to limit perceptibility with embedding information. Transform domain is more popular to achieve the required results in color image watermarking. Variants of complex Hadamard transform (CHT) have been applied for gray image watermarking, and it has been proved that it has better performance than other orthogonal transforms. This paper is aimed at analyzing the performance of spatio-chromatic complex Hadamard transform (Sp-CHT) that is proposed as an application of color image watermarking in sequency domain (SD).

In this paper, color image watermarking technique is designed and implemented in SD using spatio-chromatic – conjugate symmetric sequency – ordered CHT. The color of a pixel is represented as complex number a*+jb*, where a* and b* are chromatic components of International Commission on Illumination (CIE) La*b* color space. The embedded watermark is almost transparent to human eye although robust against common signal processing attacks.

Based on the results, bit error rate (BER) and peak signal to noise ratio are measured and discussed in comparison of CIE La*b* and hue, saturation and value color model with spatio-chromatic discrete Fourier transform (Sp-DFT), and results are also analyzed with other discrete orthogonal transforms. It is observed from BER that Sp-CHT has 8%–12% better performance than Sp-DFT. Structural similarity index has been measured at different watermark strength and it is observed that presented transform performs better than other transforms.

This work presents the details and comparative analysis of two orthogonal transforms as color image watermarking application using MATLAB software. A finding from this study demonstrates that the Complex Hadamard transform is the competent candidate that can be replaced with DFT in many signal processing applications.

The purpose of this paper is to provide a technique that helps in completing the automation cycle in e‐government and e‐business transactions. Some e‐government and e‐business transactions require the physical intervention of a user or an employee to place a physical stamp or a hand signature on a document. This paper suggests a digital watermarking approach for online hand signatures and physical stamps. The suggested technique may be used by individuals or organizations to place hand signatures and stamps on remote documents.

The work started by surveying existing security protocols and authentication techniques. Digital watermarking techniques have then been deeply studied to investigate their security capabilities and effect on the performance of the system. A scenario‐based approach has then been used to derive a number of secure digital watermarking protocols that may be used to place remote physical signatures and stamps. The derived protocols were then audited and tested.

It is possible to design and build simple light watermarking protocols for placing authentic hand signatures and stamps on remote documents (online). The process is secure and reliable.

The suggested technique will greatly improve and speed e‐government and e‐business transactions.

According to one's own knowledge and the surveys so far conducted, the suggested system is the first of its kind.

Aims to report a novel method of estimating the geometric manipulation to which present day data hiding is subjected.

Computes the feature points matching measure for the geometric manipulation using shape‐specific points. The feature points matching is realized by simulated annealing algorithm.

Finds that the purposed scheme does not require the original image because reference point information on the original image has been contained in the secret key.

Experiments herein have proved the method's robustness in face of geometric attacks and a new way of designing a better blind secret message decodes has been revealed.

Fueled by the rapid growth of internet, steganography has emerged as one of the promising techniques in the communication system to obscure the data. Steganography is defined as the process of concealing the data or message within media files without affecting the perception of the image. Media files, like audio, video, image, etc., are utilized to embed the message. Nowadays, steganography is also used to transmit the medical information or diagnostic reports. The paper aims to discuss these issues.

In this paper, the novel wavelet transform-based steganographic method is proposed for secure data communication using OFDM system. The embedding and extraction process in the proposed steganography method exploits the wavelet transform. Initially, the cost matrix is estimated by the following three aspects: pixel intensity, edge transformation and wavelet transform. The cost estimation matrix provides the location of the cover image where the message is to be entrenched. Then, the wavelet transform is utilized to embed the message into the cover image according to the cost value. Subsequently, in the extraction process, the wavelet transform is applied to the embedded image to retrieve the message efficiently. Finally, in order to transfer the secret information over the channel, the newly developed wavelet-based steganographic method is employed for the OFDM system.

The experimental results are evaluated and performance is analyzed using PSNR and MSE parameters and then compared with existing systems. Thus, the outcome of our wavelet transform steganographic method achieves the PSNR of 71.5 dB which ensures the high imperceptibility of the image. Then, the outcome of the OFDM-based proposed steganographic method attains the higher PSNR of 71.07 dB that proves the confidentiality of the message.

In the authors’ previous work, the embedding and extraction process was done based on the cost estimation matrix. To enhance the security throughout the communication system, the novel wavelet-based embedding and extraction process is applied to the OFDM system in this paper. The idea behind this method is to attain a higher imperceptibility and robustness of the image.

Steganography is a data hiding technique used in the data security. while transmission of data through channel, no guarantee that the data is transmitted safely or not. Variety of data security techniques exists such as patch work, low bit rate data hiding, lossy compression etc. This paper aims to increase the security and robustness.

This paper describes, an approach for multiple images steganography that is oriented on the combination of lifting wavelet transform (LWT) and discrete cosine transform (DCT). Here, we have one cover image and two secret images. The cover image is applied with one of the different noises like Gaussian, Salt & Pepper, Poisson, and speckle noises and converted into different color spaces of YCbCr, HSV, and Lab.

Due to the vast development of Internet access and multimedia technology, it becomes very simple to hack and trace secret information. Using this steganography process in reversible data hiding (RDH) helps to prevent secret information.

We can divide the color space converted image into four sub-bands of images by using lifting wavelet transform. By selecting lower bands, the discrete cosine transform is computed for hiding two secret images into the cover image and again one of the transformed secret images is converted by using Arnold transform to get the encrypted/embedded/encoded image. To extract the Stego image, we can apply the revertible operation. For comparing the results, we can calculate PSNR, SSIM, and MSE values by applying the same process for all color spaces of YCbCr, HSV, and Lab. The experimental results give better performance when compared to all other spaces.

The purpose of this paper is to illustrate some methods to protect digital libraries using digital rights management (DRM) technologies and specifically the methods applied at the digital libraries of Jordan universities.

A descriptive research method has been used to examine the extent of DRM in digital libraries of universities in Jordan.

Majority of the universities in Jordan use different methods of protection including coding, identification, authenticity and digital watermark. However, methods including digital signature, digital fingerprint, copy detection systems and pay system have not been employed within Jordanian universities. The use of copyright management systems has been limited, which shows the weakness in the use of technological protection within the investigated libraries.

This study has shown contribution to the development of digital libraries that are based on the protection of new technology and are able to provide better services to users without concern about protecting publishers’ rights.