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This paper presents a real-time high-definition 720p@30fps H.264/MPEG-4 AVC intra-frame codec IP suitable for digital video and digital still camera applications. The whole design is optimized in both the algorithm and architecture levels. In the algorithm level, we propose to remove the area-costly plane mode, and enhance the cost function to reduce hardware cost and to increase the processing speed while provide nearly the same quality. In the architecture design, in additional to the fast module implementation the process is arranged in the macroblock-level pipelining style together with three careful scheduling techniques to avoid the idle cycles and improve the data throughput. The whole codec design only needs 103 K gate count for a core size of 1.28 × 1.28 mm² and achieves real-time encoding and decoding at 117 and 25.5 MHz, respectively, when implemented by 0.18-μm CMOS technology. [ABSTRACT FROM AUTHOR]

A novel reversible data hiding algorithm, which can recover the original image without any distortion from the marked image after the hidden data have been extracted, is presented in this paper. This algorithm utilizes the zero or the minimum points of the histogram of an image and slightly modifies the pixel grayscale values to embed data into the image. It can embed more data than many of the existing reversible data hiding algorithms. It is proved analytically and shown experimentally that the peak signal-to-noise ratio (PSNR) of the marked image generated by this method versus the original image is guaranteed to be above 48 dB. This lower bound of PSNR is much higher than that of all reversible data hiding techniques reported in the literature. The computational complexity of our proposed technique is low and the execution time is short. The algorithm has been successfully applied to a wide range of images, including commonly used images, medical images, texture images, aerial images and all of the 1096 images in CorelDraw database. Experimental results and performance comparison with other reversible data hiding schemes are presented to demonstrate the validity of the proposed algorithm. [ABSTRACT FROM AUTHOR]

In this paper, we propose a balanced multiple description video coding scheme which is based on the partitioning of the discrete cosine transform (DCT) coefficients. Our scheme splits the single-layered stream generated by a standard coder into two correlated and balanced (virtually identical rates and distortions) substreams. The optimization is in the redundancy-rate-distortion sense using Lagrangian relaxation for optimum allocation of redundancy among the blocks in the frame. A greedy algorithm to meet the equal distortions criterion and an algorithm to optimally achieve equal bit rates for the two descriptions are proposed. Our simulation results substantiate our claim of achieving balanced descriptions at high peak signal-to-noise ratios values for any specified redundancy and any target bit rate. Our design compiles with the existing motion-compensated DCT-based standards, i.e., each description can be independently decoded by any standard decoder. [ABSTRACT FROM AUTHOR]

This paper describes a new family of three-dimensional (3-D) representations for computer graphics and animation, called depth image-based representations (DIBR), which have been adopted into MPEG-4 Part16: Animation Framework extension (AFX). Idea of the approach is to build a compact and photorealistic representation of a 3-D object or scene without using polygonal mesh. Instead, images accompanied by depth values for each pixel are used. This type of representation allows us to build and render novel views of objects and scene with an interactive rate. There are many different methods for the image-based rendering with depths, and the DIBR format is designed to efficiently represent the information necessary for such methods. The main formats of the DIBR family are SimpleTexture (an image together with depth array), PointTexture (an image with multiple pixels along each line of sight), and Octreelmage (octree-like data structure together with a set of images containing viewport parameters). In order to store and transmit the DIBR object, we develop a compression algorithm and bitstream format for Octreelmage representation. [ABSTRACT FROM AUTHOR]