USGS MIPS Decstr Documentation

USGS MIPS Decstr Documentation

This program applies a decorrelation stretch to multiple images . That is, it first decorrelates the input images by transforming them into principal component images, then a linear stretch is applied to each of the principal components, and finally the stretched images are transformed back using the inverse principal component equations.

Files

This program requires as input an eigenvector file and two to seven unsigned 8-bit image files. It will produce two to seven unsigned 8-bit image files depending on the number of input image files. The following information is transfered from the input files to the output files(if appropriate):

Image labels
Mosaic labels
Sonar labels
Navigation file
Projection labels
History file

The eigenvector file must be produced using the program STATS. Also, the input image files must be entered in the same order for both STATS and DECSTR in order to get the proper results.

Parameters

MIN and MAX: These parameters are arrays used to define valid DNs in the input images. Element one of each array corresponds with input image one, element two with input image two, etc. Thus each input image has its own min/max pair. Prior to applying the principal component equations to each pixel location in the images, the DNs are examined to see if it they are in the appropriate min/max range. If all DNs are valid then the equations are applied otherwise all DNs at that pixel location in the output principal component images are set to 0. The default values are 0 and 255 for all input images.
OFFSET: This parameter is an array of offsets which are used to keep the results of the principal components within the DN range of 0 to 255. The default values are determined by the STATS program and are stored in the eigenvector file. The first element is the offset for the first principal component and is generally negative but varies. The second, third, etc, elements are the offsets for their respective principal component images and always default to a DN of 127.
LOWPER and HIGHPER: These parameters are arrays used to select minimum and maximum cumulative percentages to be used in applying a linear stretch to the principal component images. The default values are 0.25 for Lowper and 99.75 for Highper for all input images.

Examples

From left to right, color composite of original Landsat TM Bands 2/4/5 with no stretch, color composite of Landsat TM Bands 2/4/5 with linear stretch applied and color composite of Landsat TM Bands 2/4/5 with decorelation stretch applied.

[Example Image]