User's Guide

RADIOM2

Applies radiometric lookup tables (RLUTs) to a BYTE image.

Function:

RADIOM2 applies radiometric lookup tables (RLUTs) to a BYTE input image to yield a new radiometrically corrected output image. RADIOM2 receives input RLUTs from HISTEQ.

Parameters:

IN
Input image. Image to be radiometrically corrected. Must be a BYTE image.

INRLUT
Input radiometric lookup table file. Created by running HISTEQ on the same input image.

OUT
Output image. Radiometrically corrected image.

Example:

  1. LAS> radiom2 in=image.dat inrlut=image out=image.rad

    RADIOM2 applies the RLUT, IMAGE;RLUT, to IMAGE.DAT. The output image is IMAGE.RAD.

Description/Algorithm:

RADIOM2 applies radiometric lookup tables (RLUTs) stored in an RLUT file to an input image to produce a radiometrically corrected output image.

Each line of the input image is associated with a specific detector. This uniquely determines the node within the RLUT file at which the appropriate table is stored. Once the table is located and read, the input pixels are mapped according to the table and written to the output image.

Non-fatal Error Message:

  1. [radiom2-band] WARNING: Band number in image: nn, and in RLUT file: mm

    The band number(s) in the image and the RLUT file do not match. Recreate the RLUT file, or respecify the image.

Fatal Error Messages:

  1. [radiom2-dtype] Input image must be BYTE

    RADIOM2 accepts only images of BYTE data type.

  2. [radiom2-nbands] Number of bands in image: nn and in RLUT file: mm

    The dimensions of the image and the RLUT do not match. Recreate the RLUT file, or respecify the input image.

User Notes:

  1. The input RLUT file is obtained by running the program HISTEQ. A typical processing scenario is as follows: 

            o Run the program HISTEQ on the image to generate 
          the RLUTs.

        o Run RADIOM2 with these RLUTs to radiometrically 
          correct the image.

  2. RADIOM2 assumes that the image is a TM image if the number of detectors is 16, and applies the RLUTs for detector 16 to line 1, detector 15 to line 2, and so on.

  3. RADIOM2 assumes that the image is an MSS image if the number of detectors is 4.