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(b) Display equalized histogram. 
(c) Display regular image. 
(d) Display equalized image. 
Notices 
A list of a program doing about the same work except that the hyp 
erpixel size is 2x2 = 4 single pixels of the PC-CGA graphics card 
which will be worked in medium resolution color graphics mode on a 
monochrome display, will be available to you with the restriction 
to look at it and keep hand written notes. You are not allowed to 
copy that program or use exactly the same code. The same program 
is available for execution only, it is located in the file LAB9.EXE 
Wanted (a) The program list with source code. 
(b) A copy of the regular histogram in a dot matrix printer using 
PrtSc command. 
(c) A copy of the equalized histogram in a dot matrix printer 
using PrtSc command. 
(d) A copy of the regular image in a dot matrix printer using 
PrtSc command. 
(d) A copy of the. equa1ized image in a dot matrix printer using 
PrtSc command. 
GIS Lab assignment 8. PERSPECTIVE DRAWING 
Write a computer program and make a perspective presentation of 
the given digital terrain data which are in a matrix form 21-rows 
by 27 columns end reside in the file LABS.DAT. The perspective 
form will be obtained by assuming that a camera with focal length 
equal to one is taking a picture of the terrain. 
Given data will be (see also Fig. 1): (a) The digital terrain 
date in a matrix form (b) The XL, YL, ZL coordinates of the camera 
station (c) The angle s of the camera axis.and a horizontal plane 
(d) The azimuth Az of the principal plane. The photo-coordinates 
x, y of all grid nodes will be calculated from the following pro 
jective equations. 
(X-XL)cos(Az) - (Y-YL)sin(Az) 
x — 
- (X-XL)sin(Az)cos(s) - (Y-YL)cos(Az)cos(s) + (Z-ZL)sin(s) 
(X-XL)sin(Az)sin(s) + (Y-YL)cos(Az)sin(s) + (Z-ZL)cos(s) 
y ; 
- (X-XL)sin(Az)cos(s) - (Y-YL)cos(Az)cos(s) + (Z-ZL)sin(s) 
Note that the equations above are derived from the tilt, swing. 
Azimuth col linearity equations of photogrammetry (.swing » 180, 
90 - tilt).