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IIT 
TM data processing software 
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TM data processing software consists of four stages, which 
are designated as pass 0, pass 1 
tively( See Fig.2 ). 
stage are presented in the following. 
(1)^pass^0 
Pass O is for 
reproducing HDT recorded 
with satellite image 
data and feeding the 
image data, calibration 
data, Dl restore dala 
and PCD(payload 
correction data) 
disk memories. 
into 
Using ephemeris 
data which are telexed 
from NASA , compute 
satellite orbit infor- 
mation and determine 
HDT reading start 
time. Next,feed PCD 
into a disk memory as 
they are reproduced 
with real time speed, 
and then feed image 
data, calibration 
data as they reproduced 
with 1/16 speed. 
Histogram data which 
are generated by TMCE 
( TM control equipment) 
are also stored at the 
same time in two RM 
disks. 
(2) pass I 
Geometric Correction 
Radiometric Correction 
  
  
pass 2 and pass 3 respec- 
General descriptions of each processing 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Pass © Pass 1 — Pass 2/3 
Image 
Image Data 
Data 
Ephemeris & i 
E | iEphemeris 
Atti tude Computation 
Component 
- T attitude] Uu 
onputati | 
fengutstio]: 3 
d 
= ere Low Freq. / 
ne tude + Comment | Resampling 
rConputation along scan 
eee = ; Look up  |"i 
Table | —— 
Scan | | : Resampling 
1 Profile Min & Low] |. ross scan 
Distortion i 
Correction 
Ferd Cal. Data Res i 
ampling 
Generation ECC RR s 
* 
| | Histgram ' 
Modification Gain & 
- Offset 
L | i 
Standard + 
Deviation Look up 
Table 
Pass Q —————— Pass | 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
— Pass 2/3 
Fig. 2 Flow chart of geometric & radiometric correction 
Pass 1 computes radiometric and geometric correction co- 
efficients for removing distortions due to sensor re 
sponsivity 
characteristics and satellite attitude changes and outputting 
the image data by designated mapping projection method. 
Satellite position, velocity and at 
the edited. PCD data; 
titude are computed from 
In case of missing ephemeris data points, 
the missing data are interpolated with adjacent data points 
by the VINTI's ephemeris generation method.