Simulate an uniform out-of-focus blurring of an image.
::simulate_defocus simulates out-of-focus blurring of an image. All parts of the image are blurred uniformly. 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 null, the absolute value of Blurring is used. Simulation of blurring is done by a convolution of the image with a blurring specific impulse response. The convolution is realized by multiplication in the Fourier domain.
As the simulation of the blurring is realized based on the Fourier transform, image height and width must be a power of 2, e.g. 128, 128, 256, 512,...
|
Image (input_object) |
image -> Hobject: HImage ( any ) |
| Image to blur. | |
|
DefocusedImage (output_object) |
image -> Hobject * : HImage ( real ) |
| Blurred image. | |
|
Blurring (input_control) |
real -> HTuple.double |
| Degree of blurring. | |
| Default value: 5.0 | |
| Suggested values: 1.0, 5.0, 10.0, 15.0, 18.0 | |
::simulate_defocus returns H_MSG_TRUE if all parameters are correct. If the input is empty ::simulate_defocus returns with an error message.
::gen_psf_defocus, ::simulate_motion, ::gen_psf_motion
::wiener_filter, ::wiener_filter_ni
::gen_psf_defocus, ::simulate_motion, ::gen_psf_motion
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.
Wiener filter
