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Multi-view video is a new multimedia service which provides immersion and realism using the multiple view channels. However, as the number of cameras increases, the enormous data volume generated by them inevitably calls for better video compression and processing algorithms. However, the multiple images taken at any certain time instants always have inconsistency among the views in their intensity, color, sharpness, and so on. It not only degrades the compression efficiency greatly but also causes subjective quality loss such as dizziness and unnaturalness in random view access. To solve this problem, in this paper, we propose a new multi-view compensation method which uses the Kalman filter. It estimates the illumination discrepancy parameters autonomously both in encoder and decoder. Therefore, our method needs not transmit any additional data for illumination discrepancy information. [ABSTRACT FROM AUTHOR]

When a block is lost due to a transmission error in compressed bitstream, conventional temporal error concealment schemes try to conceal the lost block by recovering its motion vector based on some matching criteria. Since essential information for deblocking process and residual data are lost, discontinuity occurs at block boundary, and this discontinuity greatly degrades subjective quality of reconstructed video. To enhance the subjective video quality caused by the discontinuity, we propose a new temporal error concealment (TEC) technique capable of block boundary smoothing. In the proposed scheme, the extended boundary pixels in reference frame are overlapped with the lost block boundary with some weighting factor. For effective error concealment, the flexible macroblock ordering (FMO) technique in H.264 standard is used. The experimental results show that the proposed method provides enhanced subjective quality especially in homogeneous region. [ABSTRACT FROM AUTHOR]

As the amount of digitalized contents increases rapidly, `security΄ necessarily arises as one of the most important issues. The main distribution channel of digital contents is Internet which is very easily accessible. Therefore content protection becomes a major issue as important as data coding techniques. In recent years, many developers have studied techniques that allow only authorized person to access contents. Among them, scrambling is one of well-known security techniques. In this paper, we propose a simple and effective digital video scrambling method which utilizes the intra block properties of a recent video coding technique, H.264. In addition to its simplicity, the proposed method does not cause bit rate increase after scrambling. [ABSTRACT FROM AUTHOR]

In compressed data, there is not enough room available for data hiding, consequently many data hiding methods try to modify original data before compression. One of well-known lossless compression methods is LZW. It has been widespread due to wide use of GIF format. In spite of its reputation on compression, however, few data hiding methods are directly applicable to LZW itself. This may be due to few redundancies remained in losslessly compressed data. In this paper, we propose the DH-LZW method that embeds a certain message to source data in a lossless manner. Forced update method and an efficient data embedding scheme are proposed to be used. Finally, we show promising experimental results. [ABSTRACT FROM AUTHOR]

In this paper, we propose an efficient traffic smoothing method for MPEG–4 Part–10 AVC/H.264 bitstream over wireless network. In general, the conventional traffic smoothing schemes try to reduce network congestion, however the main target of the proposed method is to reduce artifacts such as frame skip, occurred at the receiver. The proposed method consists of packet-based windowing and probing method. It can be efficiently applicable to the slice structure of H.264, and reduce computation complexity. In our experimental results, the proposed method shows promising results, which maximizes the degree of traffic smoothing and minimizes the frame skip count of receiver adaptively. [ABSTRACT FROM AUTHOR]