Hao-Song Kong

Fast adaptive fuzzy post-filtering for coding artifacts removal in interlaced video

The paper presents a new method using fuzzy filtering to remove the coding artifacts in compressed video. The method takes the interlaced video format into consideration and processes each field separately. For deblocking, a 1D fuzzy filter with different window sizes is used to remove the horizontal and vertical blocking artifacts respectively. For deringing, each 8/spl times/8 block in a field is first classified into one of the four categories, i.e., strong edge, weak edge, texture and smooth blocks. According to each blocks type and the neighboring blocks type, the spread parameter of a 2D fuzzy filter is adaptively decided and the filter is applied To speed up the process, the fuzzy filter weights are generated using a piecewise linear membership function instead of the conventional Gaussian function. Experimental results show that the proposed method has better detail preservation and lower computational costs than our previous method. It achieves comparable deblocking and superior deringing performance to the MPEG-4 standard method at similar computation costs.

ROI-based SNR scalable JPEG2000 image transcoding

This paper presents a quality scalable Region-of-Interest (ROI) transcoding technique for JPEG2000 image transmission over narrowband networks. The proposed scheme employs a structure analysis of the bitstream, packet extraction and reorganization, as well as a prioritization of ROIs and background with desired qualities. Since the proposed scheme does not involve any re-encoding operation, either for the wavelet coefficients or for the packet header, it has very low complexity. This paper studies the output picture quality of various transcoder configurations, discusses the bandwidth savings achieved by the scheme and also presents a complexity evaluation. Experimental results show that significant bandwidth reduction for image transmission is achieved and image quality for monitoring surveillance video is maintained with a very minimal amount of complexity in the transcoder.

Coding Mode Optimization for MPEG-2 Transcoding with Spatial Resolution Reduction

This paper presents a coding mode decision algorithm for MPEG-2 spatial transcoding. The optimization for coding mode and quantization scale are formulated in an operational rate distortion sense and solved by Lagarange multiplier method. The experimental results show that the proposed transcoder with optimized coding mode and quantizer can achieve better quality and lower bit rate than those obtained using cascaded transcoder or MPEG-2 TM5 encoder.

A Platform for Real-Time Content Adaptive Video Transmission Over Heterogeneous Networks

In this paper, we present a real-time adaptive streaming video platform. This platform is fully compliant with the Internet Streaming Media Alliance Implementation Specification. It has been used for experiments of Real-time video streaming and transcoding via unicast and multicast over heterogeneous networks. One of the examples of streaming video over a lossy channel is given, and a simple and efficient scheme for the packet loss recovery is presented.