Adaptation and improvement of CCITT reference model 8 video coding for digital storage media applications

摘要

Digital storage media like CD, CD-ROM, MOD, DAT, etc. open new fields of application, e.g. for storage and retrieval of moving video information for multimedia services. This paper describes a video codec operating at a bit rate supported by these media, focus being on 1.15 Mbits/s for net video. It is based on the hybrid DPCM/DCT scheme of CCITT Reference Model 8 which had been optimized within CCITT Study Group XV for telecommunications applications at bit rates ranging from 64 kbits/s to 2 Mbits/s. New building blocks have been added to implement trick modes and to improve subjective picture quality. Periodic coding of frames in an intraframe mode provides random access and, thus, fast search and reverse playback features. Adapted coder control, zoom and pan compensation, half pel accuracy of local motion vectors, weighting of transform coefficients, and noise reduction in the coding loop are the main components improving subjective picture quality for the wider range of TV applications.