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Progressive transmission of multimedia can be commonly encountered in multimedia communications. In this paper, we develop the reversible data hiding scheme for ownership protection of color images, which is suitable to meet the characteristics of progressive transmission. With progressive transmission, data can be partitioned into base and enhancement layers. We consider carefully altering the difference values between base and enhancement layers in each color plane of progressively transmitted images, and utilize the correlations between different color planes for making reversible data hiding possible. Simulation results with our scheme demonstrate the effectiveness for practical implementations with color images, and hence the ownership protection of progressively transmitted media can be retained, and original color image can be recovered.

In terms of software engineering, legacy systems cause a lot of problems in maintenance. A web application may quickly become legacy due to the fast evolution of web technology. Therefore, a transition method for migrating a web application from old to modern technology is needed. In this paper, a three-phase transition method is proposed. The API of the web application is determined in the first phase. To focus on the API and user interface definition, the concept of adapter service is introduced. The users are encouraged to participate in the prototyping process that refines the API and user interface iteratively. In the second phase, the developers focus on implementing a production-grade web service that conforms to the adapter service. In the third phase, the developers focus on the administrative tasks such as data migration, application deployment, and configuration. To demonstrate the effectiveness of the method, a case study is provided at the end of the paper.

Visual cryptography is an effective means for ownership protection of multimedia contents. Due to the massive amount of multimedia contents, compression is an inevitable part before transmission over channels. Recently, compressed sensing has attracted much attention with its superior performance in data compression. With compressed sensing, few amounts of coefficients are able to obtain reconstructed image with acceptable quality. In order to protect the ownership of multimedia contents with compressed sensing, we hide visual cryptography information, or shares, into compressed sensing coefficients. Besides, considering the characteristics of visual cryptography, compressed sensing coefficients are split into chunks for delivering over multiple channels. After reception, extracted shares can be verified to protect the ownership. Simulation results have pointed out that our method can be applicable, and integration with robust visual cryptography may lead to enhanced performances.

In this study, low-profile triple-band planar dipole antenna is proposed for long term evolution and wireless local area network applications. A symmetric combination of rectangular, meander line and stub is etched on the metallic layer of a single sided printed circuit board to form the coplanar dipole antenna. The size parameters of the proposed antenna are changed to design and fabricate the antenna which can be operated at 1800/2400/2600/5100 MHz successfully. We use IE3D software to design antenna and choose the better parameters to manufacture the proposed antenna. The influences of dimension parameter of the proposed antenna on the resonant frequency and impedance bandwidth are described. The peak gains of the fabricated antenna are 3.03dBi, 2.92dBi, 4.8dBi and 2.03dBi at 1800MHz, 2400MHz, 2600MHz and 5100MHz, respectively. It can be used in LTE 1800/2600MHz and WLAN 2.4/5GHz frequency bands.

In this paper, we propose a binary value based progressive image watermarking approach for digital right protection. The proposed method embed most watermark information into region of interest(ROI) of an image. Therefore, a client on Internet can decode the watermark while receiving the image, moreover, most watermark information would be decoded while the ROI of the image is received. In order to increase information density embedded in ROI, a transform similar to the DWT (Discrete Wavelet Transform) is applied on a binary watermark, and embed the transformed coefficients in appropriate region of the image. On the other hand, while extracting watermark, it is necessary to determine the ROI of the image and extract the transformed watermark coefficients embedded. The last step for extracting watermark is collocating all parameters to extract the original watermark by using a inverse transform similar to IDWT (Inverse DWT). With the method proposed, most potion of watermark could be extracted even when only ROIs are available. Experiment results show that the proposed watermarking scheme has not only excellent robustness and imperceptibility, but also early detection capability to deal with JPEG2000 images.

Reversible data hiding has attracted more and more attention in recent years. With reversible data hiding, it requires embedding secret data into original image with devised algorithm at the encoder, and marked image can then be delivered to the decoder. At the decoder, both the secret data and original image should be perfectly separated from marked image to keep the reversibility. There are several practical ways to make reversible data hiding possible, and one of the latest methods belongs to the prediction-based method. By carefully manipulating differences between predicted and original images, reversible data hiding can be achieved. We propose an enhanced method for manipulating the difference histogram, and we observe the better performances than existing scheme in literature. Possible ways for enhancing embedding capacity are also pointed out for the extension of our method in the future.