MultiSpec

MultiSpec is a processing system for interactively analyzing Earth observational multispectral image data such as that produced by the Landsat series of Earth satellites and hyperspectral image data from current and future airborne and spaceborne systems such as AVIRIS. The primary objective of MultiSpec is as an aid to export the results of our research into devising good methods for analyzing such hyperspectral image data. It has also found significant use in other applications such as multiband medical imagery and in K-12 and university level educational activities. There are currently in excess of several thousand known, registered users.

• The implementation should be on a readily available computer platform which has adequate processing power, but is financially within the reach of any Earth science researcher (i.e., computer platforms < $2000).
• The system should be easy to learn and easy to use, even for the infrequent user, using the most modern of software environments.
• The system should provide for easy import of data in a variety of formats, and easy export of results, both in thematic map and in tabular form.

• A change was made so that Landsat 4 files will be handled correctly when selecting all of them to be linked together as a single file similar to the process for Landsat 5 data files.
• The ability to read the meta data in the Land Information System (LIS) netcdf files was added so that the projection information could be obtained along with the fill data value.
• A new parameter was added to the image description dialog window to allow one to view and/or enter the 'no data' or 'fill data' value for the scene. This parameter is read from the file when available. The data value is also saved in output geotiff image files. The information is written in the geotiff tag that gdal has defined; therefore it can be read by packages that use gdal.
• The statistics that are computed for classes will ignore these data values. You can turn this affect off by turning off the check box for the 'no data' values in this dialog window.
• One can hold the shift key down when selecting a grouped data set in hdf4, hdf5 or netcdf files to indicate that only the selected data set is to be used. (Grouped data sets are indicated by the _Gn suffex.) One will notice that only one data set is selected by observing that the number of channels for the selection will change to 1.
• Changes were made to keep settings of data type, band interleave, header format and output file in better sync with what is possible for the selected file format. For example one cannot have a tiff/geotiff file which is band interleaved by line.
• The capability was added so users can save the output thematic image files as either geotiff files or ERDAS .gis files.
• Also a new feature was added to allow one to mosaic two images top to bottom. This processor was originally created to allow one to mosaic two Landsat quad scene together side by side ... way back when Landsat data were distributed as 4 separate quad scenes. The ability to combine two image file top and bottom is much more flexible than the append-to option in Reformat->Change Image File Format processor. One can combine images with different band interleave formats, data types and file header formats. The top - bottom capability was added so that users have an easy way to combine two granules of MODIS NDVI data that one obtains from the USGS glovis site.