gen_psf_defocus
— Generate an impulse response of an uniform out-of-focus blurring.
gen_psf_defocus
generates an impulse response (spatial domain)
of an uniform out-of-focus blurring and writes it into an image of
HALCON image type real
.
Blurring
specifies the extent of blurring by defining
the “blur radius” (out-of-focus blurring maps each image pixel on a small
circle with a radius of Blurring
- specified in “number of
pixels”). If specified less than zero, the absolute value of
Blurring
is used.
The result image of gen_psf_defocus
encloses an spatial
domain impulse response of the specified blurring. Its representation
presumes the origin in the upper left corner. This results in the
following disposition of an NxM sized image:
first rectangle (“upper left”): (image coordinates xb = 0..(N/2)-1, yb = 0..(M/2)-1)
- conforms to the fourth quadrant of the Cartesian coordinate system, encloses values of the impulse response at position x = 0..N/2 and y = 0..-M/2
second rectangle (“upper right”): (image coordinates xb = N/2..N-1, yb = 0..(M/2)-1)
- conforms to the third quadrant of the Cartesian coordinate system, encloses values of the impulse response at position x = -N/2..-1 and y = -1..-M/2
third rectangle (“lower left”): (image coordinates xb = 0..(N/2)-1, yb = M/2..M-1)
- conforms to the first quadrant of the Cartesian coordinate system, encloses values of the impulse response at position x = 1..N/2 and y = M/2..0
fourth rectangle (“lower right”): (image coordinates xb = N/2..N-1, yb = M/2..M-1)
- conforms to the second quadrant of the Cartesian coordinate system, encloses values of the impulse response at position x = -N/2..-1 and y = M/2..1
This representation conforms to that of the impulse response parameter of
the HALCON-operator wiener_filter
. So one can use
gen_psf_defocus
to generate an impulse response for
Wiener filtering.
Psf
(output_object) image →
object (real)
Impulse response of uniform out-of-focus blurring.
PSFwidth
(input_control) integer →
(integer)
Width of result image.
Default value: 256
Suggested values: 128, 256, 512, 1024
Typical range of values: 1
≤
PSFwidth
PSFheight
(input_control) integer →
(integer)
Height of result image.
Default value: 256
Suggested values: 128, 256, 512, 1024
Typical range of values: 1
≤
PSFheight
Blurring
(input_control) real →
(real)
Degree of Blurring.
Default value: 5.0
Suggested values: 1.0, 5.0, 10.0, 15.0, 18.0
gen_psf_defocus
returns 2 (H_MSG_TRUE) if all parameters are
correct.
simulate_motion
,
gen_psf_motion
simulate_defocus
,
wiener_filter
,
wiener_filter_ni
simulate_defocus
,
gen_psf_motion
,
simulate_motion
,
wiener_filter
,
wiener_filter_ni
Reginald L. Lagendijk, Jan Biemond: Iterative Identification and Restoration
of Images, Kluwer Academic Publishers Boston/Dordrecht/London, 1991
M. Lückenhaus:“Grundlagen des Wiener-Filters und seine Anwendung in der
Bildanalyse”; Diplomarbeit;
Technische Universität München, Institut für Informatik;
Lehrstuhl Prof. Radig; 1995.
Foundation