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  README
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  The Corpus
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  This folder includes the corpus of hyperspectral and multispectral images
  used for compression testing and evaluation in the course of developing
  the CCSDS-123.0-B-1 recommendation.

  The corpus includes images from the following instruments:

    - Atmospheric Infrared Sounder (AIRS),
    - Compact Reconnaissance Imaging Spectrometer for Mars (CRISM),
    - Moon Mineralogy Mapper (M3),
    - Hyperion,
    - SWIR Full Spectrum Imager (SFSI),
    - Airborne Visible/Infrared Imaging Spectrometer (AVIRIS),
    - Compact Airborne Spectrographic Imager (CASI),
    - Moderate Resolution Imaging Spectroradiometer (MODIS),
    - Landsat,
    - PLEIADES High Resolution (HR),
    - Vegetation,
    - and Système Pour l'Observation de la Terre 5 (SPOT5) High Resolution
      Geometric (HRG).

  The corpus also includes images from Infrared Atmospheric Sounding
  Interferometer (IASI) and Meteosat Second Generation (MSG) instruments.
  However, images for these two instruments are not available for public
  distribution. Note that restrictions on the use of some of the images
  may apply.

  More information regarding the technical characteristics of the corpus can
  be found in the Informational Report CCSDS 120.2-G.

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  Image Format
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  Images are available in a raw format (i.e., without any header or coding)
  as "*.raw" files. The name of each file contains the data type employed
  to store the data, and contains the image dimensions. All files are stored
  in Band Sequential Order (BSQ).

  File names employ the following pattern:
	[sensor]_[image]-[datatype]-[bands]-[rows]-[columns][-trans].raw

  [datatype] contains either u16be indicating unsigned 16-bit big-endian
  integers, or s16be indicating two's complement signed 16-bit big-endian
  integers.
  
  [-trans] is optionally appended to images to indicate that the original
  image has been transposed by changing rows by columns, usually, to better
  deal with streaking artifacts.

  For example the image "Landsat_agriculture-u16be-6x1024x1024.raw", is an
  8-bit image, stored as a 16-bit image, using unsigned big-endian integers.
  The image has 6 bands, 1024 rows, and 1024 columns. Hence, the image size
  is 2×6×1024×1024 = 12,582,912 bytes.

  For convenience, "*.raw" files are not available as is, but compressed
  using Gzip (RFC 1952) as "*.raw.gz" files.

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  Compressed Images
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  In addition to the "*.raw" files, the images are also available encoded
  following the CCSDS-123.0-B-1 recommendation as "*.fl" files. These files
  can be decompressed by compliant implementations.

  Coding options, as reported in the image headers, are included in a
  human-readable format as "*.fl.options" files.

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  Previews
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  Previews of the images are also available as JPG files, either containing a
  single band of the image or a false-color composition. These files are only
  illustrative of the original image contents, as they have been processed by
  image processing software, for example to normalize the intensity values.

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  Checksums
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  Checksums for "*.raw" and "*.fl" images are provided both in MD5 (RFC 1321)
  and SHA256 (RFC 4634) in the "md5-checksums.txt" and "sha256-checksums.txt"
  files, respectively.