ASA_IM_DECODE(1)

NAME
asa_im_decode - asa_im_decode

SYNOPSIS
asa_im_decode <asa_im> <asa_ins> <out> <outType> <near_range>

DESCRIPTION
This program is part of GMTSAR.

*** asa_im_decode v1.1 by smb ***

Decodes Envisat ASAR Image Mode Level 0 data.

asa_im
    input image file(s) (multiple files if merging along-track)

asa_ins
    input auxiliary instrument characterization data file

out output raw data file

outType
    output file type (1=byte,4=float)

near_range
    near range to which to align all lines (0=use first line near range)

Notes:

out is a complex file with no headers (byte/float I1, byte/float Q1, byte/float I2, byte/float Q2, ...)

if outType is byte, then the decoded floats are multiplied by 127.5, shifted by 127.5, rounded to the nearest integer and limited to the range 0-255

starting range computed as (rank*pri+windowStartTime)*c/2 where rank is the number of pri between transmitted pulse and return echo

calibration/noise lines are replaced with previous echo data line

missing lines within a data set and between adjacent along-track data sets are filled with zeroes in float mode and 0.*127.5+127.5 + .5 = 128 for byte mode

auxiliary data files can be found at http://envisat.esa.int/services/auxiliary_data/asar/

Envisat ASAR Product Handbook, Issue 1.1, 1 December 2002 can be found at http://envisat.esa.int/dataproducts/asar/CNTR6-3-6.htm#eph.asar.asardf.0pASA_IM__0P

*** asa_im_decode v1.1 by smb ***

Decodes Envisat ASAR Image Mode Level 0 data.

Usage: asa_im_decode <asa_im> <asa_ins> <out> <outType> <near_range>

asa_im
    input image file(s) (multiple files if merging along-track)

asa_ins
    input auxiliary instrument characterization data file

out output raw data file

outType
    output file type (1=byte,4=float)

near_range
    near range to which to align all lines (0=use first line near range)

Notes:

out is a complex file with no headers (byte/float I1, byte/float Q1, byte/float I2, byte/float Q2, ...)

if outType is byte, then the decoded floats are multiplied by 127.5, shifted by 127.5, rounded to the nearest integer and limited to the range 0-255

starting range computed as (rank*pri+windowStartTime)*c/2 where rank is the number of pri between transmitted pulse and return echo

calibration/noise lines are replaced with previous echo data line

missing lines within a data set and between adjacent along-track data sets are filled with zeroes in float mode and 0.*127.5+127.5 + .5 = 128 for byte mode

auxiliary data files can be found at http://envisat.esa.int/services/auxiliary_data/asar/

Envisat ASAR Product Handbook, Issue 1.1, 1 December 2002 can be found at http://envisat.esa.int/dataproducts/asar/CNTR6-3-6.htm#eph.asar.asardf.0pASA_IM__0P