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International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B3. Istanbul 2004 
e Mean of sigma X’s 
e Mean of sigma Y’s 
o Mean of sigma Z’s 
e Max sigma X 
e  Maxsigma Y 
a Max sigma Z 
e Min sigma X 
e Min sigma Y 
e Min sigma Z 
e No of points with accuracy of (X,Y,Z) Between : 
Y  0to 0.1 (in object space units) 
Y 0.1t0035 
Y 05101 
Y. Lto2 
Y 2to4 
Y  4to infinity 
51.3 GP 
At the beginning of a project and computations we have to 
prepare image coordinates of control points in each image, 
with this function operator can easily zoom and click on control 
points then enter number of that point and do this for all control 
points in image to obtain input for DLT METHOD . input for 
this function is only image No. this function also prepare image 
resolution (dimensions) for PREPARE SETTINGS. 
51.9 FILTER POINT CLOUD 
After forward intersection and computing ground coordinates of 
object always there are some mismatched points or gross errors 
in points calculated by intersection , these points actually 
doesn’t belong to object surface .this is because of wrong 
coordinates of conjugate points obtained by image matching . 
To remove some of these points and also obtain a regular point 
cloud on object ,this function devides object space in cubes and 
replace all points that located inside one cube with cube corner. 
Cube size and frequency of points inside a single cube are 
selected by operator .this function works in Visual Basic 6 
environment as an independent application. 
5.1.10 CREATE DXF FILE 
DXF file is a standard format that most graphical softwares 
support it.to visualize point cloud of object surface we need to 
prepare DXF file of resulting regular or irregular point cloud 
that can be seen in a CAD software such as AutoCad. This 
function that is written in Visual Basic 6 take an X,Y,Z text file 
of point cloud with format NO,X,Y,Z and prepare DXF file of 
that file. 
52 SECONDARY COMPUTATIONAL FUNCTIONS 
32.1 FORM ONE POINT COLLIN EQ 
The function uses x,y (image coordinates) and (X,Y,Z) ground 
coordinates of a point and form two collinearity equations for 
each point. these equations are in terms of unknown parameters 
XL,YL,ZL , omega , fi, kapa ,x0,y0,f, K1,K2,P1,P2 
52.2 FORM ONE IMAGE BUNDLES 
For each image point two collinearity equations can be formed 
S0 to form all possible equations from all control points in one 
image , this function uses image No and output of GP for that 
image as input and obtain all collinearity equations in image. 
5.2.3 GET IMAGE COOR 
As mentioned before in matching process , one image is 
selected as base image . to extract points on edges of this image 
this function uses black and white form of base image as input 
and yields an N by 2 matrix that is coordinates of points on 
edges in base image . 
5.2.4 GROUND POINT 
In matching process it is necessary to compute ground 
coordinate of a point in an image getting image No, image 
coordinates of point and its z coordinate in object space as 
input. This is done by collinearity equations and image 
orientation parameters. We have inputs as : 
e Image No 
e (x,y) : Image coordinates 
e Z :(object space z coordinate of point) 
And output is 
e. (X,Y): object space coordinates of point 
5.2.5 IMAGE POINT 
In image matching process it is necessary to compute image 
coordinates of a point in a particular image given (X,Y,Z) 
ground coordinates of that point . this function uses following 
inputs : 
e Image No 
e. (X,Y,Z): ground coordinates of point 
and the output is : 
e. (Xy): image coordinate in given image (image No) 
8.2.6 121 
This function uses (x,y) image coordinates of point in one 
image and also z of that point in object space and calculate 
image coordinates of this point in another image ,so inputs are: 
(x1,y1) : image coordinates of a point in image Nol 
Image Nol : first image number 
e  Zcoordinate of point in object space 
Image No2: second image number that coordinates of 
point in it is required 
And out put is 
e (x2,y2) : image coordinates in image No2 
5.2.7 FINDMATCH 
To find conjugate point in other images, since searching all 
areas of other images is so time consuming , it is possible to 
limit the search area to a line. For each point in object space 
with coordinates (X,Y,Z1) we can calculate (xl,yl) in a 
particular image .in a similar way we can find (x2,y2) for that 
point in object space but with different Z coordinate (X, Y,Z2). 
If take Z1 and Z2 maximum and minimum Z in object space 
we have a line between (x1,y1) and (x2,y2). 
This function uses (x,y) coordinates of point in one image and 
points of calculated line in image we want to find match as 
input and find the best match according normalized cross 
correlation method .so the inputs are : 
e. (xy) image coordinates of a point in base image 
    
  
   
   
    
   
   
   
    
   
     
       
   
     
    
   
    
    
   
   
   
    
  
     
     
     
    
  
   
    
   
   
     
   
   
    
    
   
    
    
   
     
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