ito the upper 
ets into the 
turn; 
le basis of 
ion of pitch 
t of a pitch 
nes. 
the previous 
ragments of 
shift, image 
z instead of 
nents of the 
t image and 
nes has an 
ft along the 
1akes about 
  
30 % from a vertical size of the image, and horizontal size - 
about 2 -3 % from a horizontal size. 
One pair of zones is displaced relative to another on a half of 
zone vertical size on an angle of elevation. At that, on curse 
zones are placed: between road marking lines in far zone on one 
image; in the center of the image on another. Placement of 
zones is controlled frame after frame. 
Fig. 2 presents the block-scheme of this procedure. 
Let's consider how this procedure works. 
Determination of the zone position displacement on course 
when angular velocity is present 
Angle A is calculated using the data of angular velocity sensor. 
Here A¢ is the angle on which it is necessary to move all zones 
for the same objects of scene getting in the zones that were in 
these zones on the previous step. 
F 
Ad= 0o At — 
m. 
Here F is focal length, m, is scale along a Z axis. 
Determination of acceptable pitch increment values 
This procedure task is to decrease number of possible etalon 
positions inside of the zone, which allows to decrease false 
operation probability and to decrease processing time. Possible 
values of pitch angle Ag; could be determined as: 
Ap; = 9; 1 At +6 
At that the relation |p;_; + A@;| < Pmax is verified where Era 
and à are defined by the vehicle dynamic characteristics. 
Calculating of a lateral histogram for each zone 
Lateral histogram is formed for each zone. To do it the sum per 
line is calculated. The result of this procedure is 4 one- 
dimensional arrays. 
Determination for each zone the contrast value, maximum 
of correlation function and appropriate pitch increment 
value. 
The maximum value of lateral histogram contrast is calculated 
for each zone by some differentiating operator. The correlation 
function R(n) is calculated, it’s maximum value found and 
position of zone relative to the etalon is determined for this 
value. 
The correlation function R(n) is calculated as 
Load ith image 
y 
  
Determination of the zone 
position displacement on course 
Q, At 
  
  
coke 
Determination of acceptable pitch 
increment values 
  
  
Calculating of a lateral histogram 
for each zone 
  
  
Y 
  
Determination for each zone the 
contrast value, maximum of 
correlation function and 
appropriate pitch increment value 
  
Y 
  
Output pitch increment value 
selection 
AQ; 
  
  
  
  
  
Current pitch angle value 
calculation 
  
  
Y 
[* Road situation analysis = 
Y 
  
  
Determination of new position for 
zones on course angle 
  
  
  
  
Calculating of lateral histograms 
of etalon images and calculation 
of contrast in every zone 
  
  
  
—575— 
  
  
  
Contrast exceed 
threshold value 
    
Fig. 2 
* - road marking lines position in Far Zone; 
** - screen coordinates of objects that are tracked; 
LE E T 
= i.i, G;. 1 , (max 
» 
> 4 (k)45 (k n) 
k=1 
1/2 1/2