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Feedback on initial draft of hyperspectral data file format #27

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dlebauer opened this Issue Apr 12, 2016 · 0 comments

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dlebauer commented Apr 12, 2016

The first sample of hyperspectral image data is ready with units of "Exposure on scale from 0 to 2^16-1 = 65535". Data available as 134MB file foo.nc and much smaller metadata text file foo.cdl.

This has been prepared using the hyperspectral/terraref.sh script.

  • People will be most interested in looking at band-specific data so the default script is simplified for this.
  • Lossless compression by Deflate is 20-25% with no loss of data with less than 5 s to decompress.
  • Higher compression will cause longer decompression time
  • Lossy compression is an option (bit rounding), then compressing with lossless compression to get an extra 10% saving per decimal digit
  • In addition to netCDF format, there is interest in geoTIFF; gdal provides tools so that we can allow conversion to geoTIFF and other files for download on demand.

Next steps include calibration and conversion of exposure to reflectance as defined in #14.

@rachelshekar rachelshekar modified the milestone: June 2016 Jul 7, 2016

@dlebauer dlebauer modified the milestones: June 2016, July 2016 Jul 11, 2016

@dlebauer dlebauer closed this Jul 11, 2016

@dlebauer dlebauer added 4 - Done and removed 3 - Review labels Jul 11, 2016

@rachelshekar rachelshekar added help wanted and removed question labels Jan 3, 2017

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