Author_Institution :
Unisys Corp., San Jose, CA, USA
Abstract :
The computational power of desktop computers (e.g. Intel 486 PC) has reached the stage where software solutions for desktop videoconferencing (DVC) are worth considering. Here, coder/decoder (CODEC) refers to video compression/decompression. In this paper, the requirements and selection criteria of software CODEC algorithms in DVC are presented. An overview of CODEC algorithms for DVC, such as Differential Pulse Code Modulation (DPCM), Discrete Cosine Transform (DCT), Wavelet, Vector Quantization, Fractal, Block Truncation Coding and Hybrid coding will give us insight into their feasibility in DVC, particularly when implemented in software. Some of the driving factors in the proliferation of DVC are: cost, platform, interoperability, communications bandwidth, availability and integrity, performance and quality, and last but not the least, collaborative applications. Most of these factors, especially interoperability, are important in choosing a software CODEC algorithm and so the standard H.261 is worth paying attention to. A quantitative analysis of some CODEC techniques is presented in a matrix
Keywords :
computer communications software; microcomputer applications; telecommunication computing; teleconferencing; video codecs; Block Truncation Coding; Differential Pulse Code Modulation; Discrete Cosine Transform; Fractal; H.261 standard; Hybrid Coding; Intel 486 PC; Vector Quantization; Wavelet; coder/decoder; collaborative applications; communications bandwidth; desktop computers; desktop videoconferencing; interoperability; matrix; software CODEC algorithms; video compression/decompression; Codecs; Decoding; Discrete cosine transforms; Discrete wavelet transforms; Modulation coding; Pulse modulation; Software algorithms; Teleconferencing; Vector quantization; Video compression;
