monitor, It has four 512+512+8 bit image frame 
memory blocks.The digital images obtained by CCD 
cam ra or from disk can be registered in one of 
the memory blocks and both be directly displayed 
on the monitor and processed in the computer. At 
present , a new multimedia board has be used 
to input image from recorder. 
2.4 Main Software 
The basic operation package which consists of 
ninety four subroutines, provided for construc- 
ting application programs .The programs written 
  
start 
| 
initialization 
| 
open frame 
| 
processing data and determining 
the window location in 20 ms 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
   
  
  
   
judeg the time 
acquering next frame ? 
    
  
  
  
close "frame" 
threshold judgement operation 
and register data operation 
  
  
  
  
  
  
no 
n times ? 
yes 
  
  
  
storing data into disk 
] 
rectification 
1 
drawing and printing 
i 
end 
  
  
  
  
  
  
  
  
  
  
  
  
  
Fig. 3 Operation Procedure 1 
  
with IBM-PC 8088 ASM,FROTRAN-77 and Turbo PASCAL 
have been provited for the function of the real- 
time tracking of the signning points, of the 
match feature point, of the registration of data, 
of the analysis of restoration, of the calcula- 
tion of 3D-coordinate , and of the analysis of 
motion track. 
  
capture stereophotograph 
| 
recording moving process 
| 
tape restoring into CV2 
| 
mark point coordi. detected 
| 
input control point coordi. 
| | 
DLT iterative solve orientation 
parametes of the camera 
solve 3D-coordinate of the feature 
end 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Fig.4 Operation Procedure 2 
3. OPERATION PROCEDURE 
This system has two oprational modes: 
1. Realtime tracking and recording of the marked 
points, then to derive and analyse of the coor- 
dinate. The procedure is shownFig. 3. 
2. Rrecording video image signal , then restore 
image by a recorder and inpute into computer for 
processing and analysing. The procedure is shown 
in Fig. 4. 
4. SEVERAL PROBLEMS 
4,1 Camera Calibration 
4.1.1 The 3D-Control Field For geometric 
calibration of the this system a three-dimension 
close range testfield is built. The testfield