gauss_image
— Smooth an image using discrete Gaussian functions.
gauss_image
is obsolete and is only provided for
reasons of backward compatibility. New applications should use the
operator gauss_filter
instead.
gauss_image(Image : ImageGauss : Size : )
The operator gauss_image
smoothes images using the discrete
Gaussian. The smoothing effect increases with increasing filter
size. The following filter sizes (Size
) are supported
(the sigma value of the Gauss function is indicated in brackets):
3 (0.65)
5 (0.87)
7 (1.43)
9 (1.88)
11 (2.31)
For border treatment the gray values of the images are reflected at
the image borders.
The operator binomial_filter
can be used as an alternative
to gauss_image
. binomial_filter
is significantly
faster than gauss_image
. It should be noted that the mask
size in binomial_filter
does not lead to the same amount of
smoothing as the mask size in gauss_image
. Corresponding
mask sizes can be determined based on the respective values of the
Gaussian smoothing parameter sigma.
gauss_image
can be executed on OpenCL devices for all supported
image types. However, the OpenCL implementation can produce slightly
different results from the scalar implementation.
For an explanation of the concept of smoothing filters see the introduction of chapter Filters / Smoothing.
In order to be able to process gauss_image
on on OpenCL device,
Image
must be at least 64 pixels in both width and height.
Note that filter operators may return unexpected results if an image with a reduced domain is used as input. Please refer to the chapter Filters.
Image
(input_object) (multichannel-)image(-array) →
object (byte* / int2* / uint2* / int4* / real*) *allowed for compute devices
Image to be smoothed.
ImageGauss
(output_object) (multichannel-)image(-array) →
object (byte / int2 / uint2 / int4 / real)
Filtered image.
Size
(input_control) integer →
(integer)
Required filter size.
Default value: 5
List of values: 3, 5, 7, 9, 11
gauss_image(Input,Gauss,7) regiongrowing(Gauss,Segments,7,7,5,100)
For each pixel: O(Size * 2).
If the parameter values are correct the operator gauss_image
returns the value 2 (H_MSG_TRUE). The behavior in case of empty input (no
input images available) is set via the operator
set_system('no_object_result',<Result>)
.
If necessary an exception is raised.
Foundation