Compression with Reversible Embedded Wavelets (CREW)
Martin Boliek
Ricoh California Research Center

CREW is a "reversible" wavelet and bit-plane lossless and lossy image compression system. It has been used with 1-12 bit deep images (the syntax provides for up to 256 bands of up to 255 bits deep). CREW is well suited for multi-resolution applications and client/server applications. The emphesis with CREW is flexibilty without sacrificing compression performance. The feature set includes

  • Both lossless and lossy compression in the same codestream
  • Quantization possible at encode, transmision, and/or decode
  • Excellent compression from lossless to very low bit-rate
  • Progressive by resolution
  • Progressive by pixel accuracy
  • Lossless color conversion
  • Continous-tone and/or binary images
  • Fixed-rate and fixed-size
  • Random access and region of interest decoding
  • Device dependent parsing before transmission
  • Idempotent for multiple compression/decompression cycles
  • Simple to implement in both hardware and software

    This talk will describe the CREW system, exposing the support for the above features. Discussion of the codestream syntax and the future for this technology will also be included.

    A short introduction to the RICOH California Research Center will also be given.

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