User's Guide

REANGLE

Recompute the 3 AVHRR angle bands for a US composite

Function:

Recompute the 3 AVHRR angle bands for a US composite

Parameters:

DATEBAND
Composite date band. The 'date band' generated during the creation of the composite. The band signifies which acquisition image each pixel in the composite came from.

SCALE
Scaling technique used to generate the composite.


US     US scaling technique

DATELOG
Date log. The log file associated with the DATEBAND image which specifies the scenes used to generate the composite. See User Note 2 for more information.

PERIODS
Period name(s). The period names that were included in the composite. For example, '008014' for a US composite (julian days 008 through 014). NOTE: This parameter is not used if the date log file specified in DATELOG is a 'short' format file (all entries in the date log file are assumed to be within the period of interest).

OUT
Output image. Image containing AVHRR channel 1 and 2 data without the effects of illumination correction. This image will be the same size and in the same space as the composite specified by DATEBAND. This image will always contain BYTE data, with "US" scaling applied, and will always be compressed.

Description/Algorithm:

For each pixel in the composite, determine the original AVHRR scene from which it came (based on the date band 'DATEBAND' and the date log file 'DATELOG'). Using the AVHRR model for the appropriate AHVRR scene, determine the 3 angle values for the pixel (solar zenith, satellite zenith, relative azimuth).

Nonfatal Error Message:

  1. [reangle-warn] Nonfatal error encountered

    A nonfatal error was encountered during processing. The error message that is displayed immediately preceding this message is the specific error that was encountered. Processing will continue.

Fatal Error Messages:

  1. [reangle-fatal] Fatal error encountered

    A fatal error was encountered during processing. Processing is terminated. The error message that is displayed immediately preceding this message is the specific error that was encountered.

  2. [reangle-badbnd] Invalid number of input bands (<X>) specified

    An input image was not specified with the correct number of bands. Examine the input image specification and rerun.

  3. [reangle-badimg] Invalid number of input images (<X>) specified

    The number of input images was not specified correctly. Examine the input image specification and rerun.

  4. [reangle-alloc] Error allocating dynamic memory

    An error occurred while trying to allocate memory. Contact the system administrator if the error persists.

  5. [reangle-band] Invalid date band specification

    A date band mismatch has occurred. Ensure that the date band image and date band log file coincide and rerun.

  6. [reangle-type] Input image must contain BYTE data

    The input image specified must be BYTE data. Specify an image with BYTE data and rerun.

User Notes:

  1. The date band log file is generated at the time the composite is generated. For a sample input date band log file, see the file 'us_232245;log' ('long' format), or the file '1992p19;log' ('short' format) stored under CVS as part of the MULLIINFO module.