change_bg_esti_params ( : : Syspar1, Syspar2, GainMode, Gain1, Gain2, AdaptMode, MinDiff, StatNum, ConfidenceC, TimeC : )

Change the parameters of the current data set

change_bg_esti_params is used to change the parameters of the current data set.The parameters passed by change_bg_esti_params are the same as in create_bg_esti (see there for an explanation).

The image format cannot be changed! To do this, a new data set with an initialization image of the appropriate format has to be created.

To exchange the background image, use update_bg_esti. The current image then has to be passed for both the input image and the update region.


Attention

If GainMode was set to 'frame', the run-time can be extremly long for large values of Gain1 or Gain2, because the values for the table fo gains are determined by a simple binary search.


Parameters

Syspar1 (input_control)
real -> real
1. system matrix parameter
Default value: 0.7
Suggested values: 0.65, 0.7, 0.75
Range of values: 0.05 <= Syspar1 <= 1.0
Recommended increment: 0.05

Syspar2 (input_control)
real -> real
2. system matrix parameter
Default value: 0.7
Suggested values: 0.65, 0.7, 0.75
Range of values: 0.05 <= Syspar2 <= 1.0
Recommended increment: 0.05

GainMode (input_control)
string -> string
gain type
Default value: 'fixed'
List of values: 'fixed', 'frame'

Gain1 (input_control)
real -> real
kalman gain / foreground adaptation time
Default value: 0.002
Suggested values: 10.0, 20.0, 50.0, 0.1, 0.05, 0.01, 0.005, 0.001
Restriction: 0.0 <= Gain1

Gain2 (input_control)
real -> real
kalman gain / background adaptation time
Default value: 0.02
Suggested values: 2.0, 4.0, 8.0, 0.5, 0.1, 0.05, 0.01
Restriction: 0.0 <= Gain2

AdaptMode (input_control)
string -> string
threshold adaptation
Default value: 'on'
List of values: 'on', 'off'

MinDiff (input_control)
real -> real
foreground/background threshold
Default value: 7.0
Suggested values: 3.0, 5.0, 7.0, 9.0, 11.0
Recommended increment: 0.2

StatNum (input_control)
integer -> integer
number of statistic data sets
Default value: 10
Suggested values: 5, 10, 20, 30
Range of values: 1 <= StatNum
Recommended increment: 5

ConfidenceC (input_control)
real -> real
confidence constant
Default value: 3.25
Suggested values: 4.30, 3.25, 2.82, 2.62
Recommended increment: 0.01
Restriction: 0.0 < ConfidenceC

TimeC (input_control)
real -> real
constant for decay time
Default value: 15.0
Suggested values: 10.0, 15.0, 20.0
Recommended increment: 5.0
Restriction: 0.0 < TimeC


Example
/* read Init-Image:*/
read_image(InitImage::'Init_Image':) >
/* initialize BgEsti-Dataset with fixed gains and threshold adaption: */
create_bg_esti(InitImage::0.7,0.7,'fixed',0.002,0.02,'on',7.0,10,3.25,15.0:) >
/* read the next image in sequence: */
read_image(Image1::'Image_1':) >
/* estimate the Background: */
run_bg_esti(Image1:Region1::) >
/* display the foreground region: */
disp_region(Region1) > 
/* read the next image in sequence: */
read_image(Image2::'Image_2':) >
/* estimate the Background: */
run_bg_esti(Image2:Region2::) >
/* display the foreground region: */
disp_region(Region2) >
/* etc. */
/* change parameter in dataset: */
change_bg_esti_params(::0.7,0.7,'fixed',0.004,0.08,'on',9.0,10,3.25,20.0:) >
/* read the next image in sequence: */
read_image(Image3::'Image_3':) >
/* estimate the Background: */
run_bg_esti(Image3:Region3::) >
/* display the foreground region: */
disp_region(Region3) > 
/* etc. */

Result

change_bg_esti_params returns TRUE if all parameters are correct.


Possible Predecessors

create_bg_esti, set_bg_esti


Possible Successors

run_bg_esti


See also

update_bg_esti



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