Adaptive predictive coding with applications to radiographs.

M Rabbani; L A Ray; J R Sullivan

PubMed · 3762451

Adaptive predictive coding with applications to radiographs.

Abstract

Picture archiving and communications systems (PACS) require storage and transmission of vast amounts of data. For design/cost considerations, it is desirable to reduce the size of these data without sacrificing the integrity of the stored information. The major considerations in designing a data-compression scheme for a PACS system are discussed: fidelity of the reconstructed image, bit rate, hardware complexity, and processing time. The basic principles of conventional nonadaptive differential pulse-code modulation (DPCM) are reviewed and compared with adaptive techniques. The effect of adaptive quantization on radiographic images is examined. Special consideration is given to block-adaptive DPCM or the "switched quantizer," which greatly enhances the system performance as compared with nonadaptive techniques, and conservatively has a 5:1 compression ratio. Sample radiographs substantiate the results.

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M Rabbani, L A Ray, J R Sullivan. Adaptive predictive coding with applications to radiographs.. https://pubmed.ncbi.nlm.nih.gov/3762451/

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