1 June 1991 Image compression for digital video tape recording with high-speed playback capability
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In a digital video tape recorder (DVTR), the video data are stored serially on a sequence of parallel scan tracks running obliquely across the tape. In normal playback, the read heads scan along each track sequentially, while fast-forward is realized by a special subsampling process in which the read heads sweep across multiple tracks per scan and pick up a segment of data from each track to generate a patchwork quilt of subimages taken from successive fields. An image compression algorithm for DVTR is required to conform to the storage format implied by this fast-forward mechanism. Thus, a field of video is partitioned into a small number of subimages, each independently coded with a fixed number of bits. This requirement excludes the use of interframe coding and most variable-rate coding algorithms. We propose a new image coding algorithm that retains the efficiency of variable-rate coding while the above requirement is satisfied. In this algorithm a subimage is partitioned into non-overlapping 8 X 8 blocks, and each block is coded progressively by DCT and Vector Quantization to generate a finite set of candidate output blocks covering a range of bit rates. A procedure based on the Lagrange Multiplier method is used to select one of the candidate outputs for each 8 X 8 block such that the overall distortion is minimized subject to the constraint on the bit rate. Simulation results demonstrate the potential of this algorithm in image compression for DVTRs.
© (1991) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Siu-Wai Wu, Siu-Wai Wu, Allen Gersho, Allen Gersho, } "Image compression for digital video tape recording with high-speed playback capability", Proc. SPIE 1452, Image Processing Algorithms and Techniques II, (1 June 1991); doi: 10.1117/12.45395; https://doi.org/10.1117/12.45395


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