This archive contains a collection of reports generated by the faculty and students of the Institute for Systems Research (ISR), a permanent, interdisciplinary research unit in the A. James Clark School of Engineering at the University of Maryland. ISR-based projects are conducted through partnerships with industry and government, bringing together faculty and students from multiple academic departments and colleges across the university.
Browsing Institute for Systems Research Technical Reports by Subject "3-D wavelet decomposition"
(1999) Jiang, Yimin; Gu, Junfeng; Baras, John S.; Baras, John S.; ISR; CSHCN
This paper presents a joint source-channel coding scheme of digital video broadcasting over satellite channels. The video compression is based on a human visual model. A perceptual distortion model, the just-noticeable-distortion (JND), is applied to improve the subjective quality of compressed videos.
3-D wavelet decomposition can remove spatial and temporal redundancy and provide scalability of video quality. In order to conceal the errors occurring under bad channel conditions, a novel slicing method and a joint source channel coding scenario that combines RCPC with CRC and utilizes the distortion information to allocate convolutional coding rates are presented. A new performance index based on JND is proposed and used to evaluate the overall performance at different signal-to-noise ratios (SNR). Our system uses the OQPSK modulation scheme.