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The P2P streaming system must have the adaptation ability to the heterogeneity of the peer nodes and networks. In this paper, an adaptive scheme on video streaming over multi-hop path in P2P networks, called server-aided intermediate node adaptive transmission (SA-INAT), is proposed. In the scheme, the streaming server probes the network parameters in the multi-hop path periodically, and adjusts the output bit-rate and the encoding structure according to the probing result. Before relay the obtained streaming data, the intermediate peer nodes elegantly discard some frames to adapt the output rate to the bandwidth while alleviating the degradation in the decoding video quality in a delay-constrained manner. The experimental results show that the video data can be streamed over the multi-hop path efficiently and adaptively by the cooperation among the streaming server and the intermediate nodes.

A local line-like feature is the most important discriminate information in the image upsampling scenario. In recent example-based upsampling methods, grayscale and gradient features are often adopted to describe the local patches, but these simple features cannot accurately characterize complex patches. In this paper, we present a feature representation of local edges by means of a multilevel filtering network, namely, multilevel modified finite Radon transform network (MMFRTN). In the proposed MMFRTN, the MFRT is utilized in the filtering layer to extract the local line-like feature; the nonlinear layer is set to be a simple local binary process; for the feature-pooling layer, we concatenate the mapped patches as the feature of local patch. Then, we propose a new example-based upsampling method by means of the MMFRTN feature. Experimental results demonstrate the effectiveness of the proposed method over some state-of-the-art methods.

H.264/AVC is the latest standard for video coding drafted jointly by the ISO/IEC Moving Picture Experts Group and the ITU-T Video Coding Experts Group. H.264/AVC provides up to 50% gain in compression efficiency over a wide range of bit rates and video resolutions compared to previous standards. On the other hand, the decoder complexity is about four times that of MPEG-2 and two times that of MPEG-4 visual simple profile. In VLSI implementations of the H.264/AVC decoder, off-chip memory access is the main time and power consuming operation, and the motion compensation module is the main memory access bottleneck. This paper proposes four optimization strategies to reduce memory access data cycles and improve memory data bus utilization. Experimental results show that about 60% data cycle reduction can be achieved and more than 20% memory data bus utilization can be improved by these strategies over typical test sequences.

This paper proposes a high efficiency memory controller for an H.264 HDTV decoder with synchronous DRAMs. As H.264 adopts tree structured (supports small block size) motion compensation, the bandwidth requirement of an H.264 HDTV decoder is higher than previous video processing algorithms. This requires to be optimized. Based on H.264 decoding data access behavior analysis, an SDRAM controller with new memory mapping method has been designed to reduce the overhead cycles of page-activation. Experiment results indicate that the new controller has improved by one-third the performance of the bus cycles. In addition, the architecture of the controller has also given low power consumption and less complexity in the VLSI design.

This paper introduces the architecture of an AVS (audio video coding standard working group of China) hardware decoding system. The system includes system layer decoding, video decoding and audio decoding. It supports 720p/1080i HD (high-definition) format real-time decoding. A VLSI chip is designed by using this architecture.

In order to reduce the bit rate of video signals, motion compensation prediction is applied in modern video coding technology. This is a form of temporal redundancy reduction in which the current coding frame is predicted by a motion compensated prediction from some other already decoded frames according to a motion vector. As real motion has arbitrary precision, many video coding standards allow motion vectors to have "sub-pixel" resolution. The 1/4-pel displacement vector resolution is a part of AVS (audio video system). In order to estimate and compensate 1/4-pel displacements, the image signal on sub-pel position has to be generated by interpolation. This paper introduces a new 1/4-pel interpolation method, named as two steps four taps interpolation (TSFT). Compared with the 1/4-pel interpolation method of H.264, 11% spatial complexity is reduced, computation complexity is about the same, and a little more average SNR is gained.

This paper introduces a new design of DC-pulse ionizing bar to solve the problem of imbalance offset voltage for the AC ionizing bar, which is easily affected by the environment, as well as indicate the final tests. The new design mainly includes five parts: power supply circuit, main control unit, logic circuit, high frequency transformer unit, and feedback unit. The ionizing bar can automatically adjust the discharge voltage, pulse frequency and pulse width to balance the positive and negative ions. The final test results indicate that the DC ionizing bar owns good effect in electrostatic elimination.

A new type of vortices called Chern-Simons vortices is considered and the existence is established.

To the Editor: Platelet glycoprotein (GP) IIb-IIIa (integrin αIIbβ3) is essential for normal hemostasis and plays a central role in platelet aggregation by binding to its adhesive ligands such as fibrinogen and von Willebrand factor. The GPIIb-IIIa is the most abundant member of the integrin