Package nom.tam.fits.compression.algorithm.hcompress

Class HDecompress

java.lang.Object
nom.tam.fits.compression.algorithm.hcompress.HDecompress
public class HDecompress extends Object
(for internal use) A hierarchical data decompression algoritm, e.g. for the Hubble Data Archive and the STScI Digital Sky Survey.

The original decompression code was written by R. White at the STScI and included (ported to c and adapted) in cfitsio by William Pence, NASA/GSFC. That code was then ported to java by R. van Nieuwenhoven. Later it was massively refactored to harmonize the different compression algorithms and reduce the duplicate code pieces without obscuring the algorithm itself as far as possible. The original site for the algorithm is

See http://www.stsci.edu/software/hcompress.html

Author:
Richard White, William Pence, Richard van Nieuwenhoven

  • Constructor Summary

    Constructors
    Constructor
    Description
    HDecompress()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    decompress(ByteBuffer input, boolean smooth, long[] aa)
    decompress the input byte stream using the H-compress algorithm input - input tiledImageOperation of compressed bytes a - pre-allocated tiledImageOperation to hold the output uncompressed image nx - returned X axis size ny - returned Y axis size NOTE: the nx and ny dimensions as defined within this code are reversed from the usual FITS notation.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • HDecompress

      public HDecompress()

  • Method Details

    • decompress

      public void decompress(ByteBuffer input, boolean smooth, long[] aa)
      decompress the input byte stream using the H-compress algorithm input - input tiledImageOperation of compressed bytes a - pre-allocated tiledImageOperation to hold the output uncompressed image nx - returned X axis size ny - returned Y axis size NOTE: the nx and ny dimensions as defined within this code are reversed from the usual FITS notation. ny is the fastest varying dimension, which is usually considered the X axis in the FITS image display
      Parameters:
      input - the input buffer to decompress
      smooth - should the image be smoothed
      aa - the resulting long tiledImageOperation