entropy_imageentropy_imageEntropyImageEntropyImageentropy_image (Operator)
Name
entropy_imageentropy_imageEntropyImageEntropyImageentropy_image — Calculate the entropy of gray values within a rectangular window.
Signature
Description
entropy_imageentropy_imageEntropyImageEntropyImageentropy_image calculates the entropy of gray values in the
image ImageImageImageimageimage within a rectangular mask of size
(HeightHeightHeightheightheight, WidthWidthWidthwidthwidth). The resulting image is
returned in ImageEntropyImageEntropyImageEntropyimageEntropyimage_entropy, in which the entropy is
multiplied by 32. If the parameters HeightHeightHeightheightheight and
WidthWidthWidthwidthwidth are even, they are changed to the next larger odd
value. At the image borders the gray values are mirrored.
Attention
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.
Execution Information
- Multithreading type: reentrant (runs in parallel with non-exclusive operators).
- Multithreading scope: global (may be called from any thread).
- Automatically parallelized on tuple level.
- Automatically parallelized on channel level.
- Automatically parallelized on domain level.
Parameters
ImageImageImageimageimage (input_object) (multichannel-)image(-array) → objectHImageHObjectHObjectHobject (byte)
Image for which the entropy is to be calculated.
ImageEntropyImageEntropyImageEntropyimageEntropyimage_entropy (output_object) (multichannel-)image(-array) → objectHImageHObjectHObjectHobject * (byte)
Entropy image.
WidthWidthWidthwidthwidth (input_control) extent.x → HTupleintHTupleHtuple (integer) (int / long) (Hlong) (Hlong)
Width of the mask in which the entropy is calculated.
Default:
9
Suggested values:
3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25
Restriction:
3 <= Width && odd(Width)
HeightHeightHeightheightheight (input_control) extent.y → HTupleintHTupleHtuple (integer) (int / long) (Hlong) (Hlong)
Height of the mask in which the entropy is calculated.
Default:
9
Suggested values:
3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25
Restriction:
3 <= Height && odd(Height)
Example (HDevelop)
read_image(Image,'fabrik')
dev_display(Image)
entropy_image(Image,Entropy,9,9)
dev_display(Entropy)
Example (C)
read_image(&Image,"fabrik");
disp_image(Image,WindowHandle);
entropy_image(Image,&Entropy,9,9);
disp_image(Entropy,WindowHandle);
Example (HDevelop)
read_image(Image,'fabrik')
dev_display(Image)
entropy_image(Image,Entropy,9,9)
dev_display(Entropy)
Example (HDevelop)
read_image(Image,'fabrik')
dev_display(Image)
entropy_image(Image,Entropy,9,9)
dev_display(Entropy)
Result
entropy_imageentropy_imageEntropyImageEntropyImageentropy_image returns 2 (
H_MSG_TRUE)
if all parameters are correct.
If the input is empty the behavior can be set via
set_system('no_object_result',<Result>)set_system("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>)set_system("no_object_result",<Result>). If
necessary, an exception is raised.
Possible Successors
disp_imagedisp_imageDispImageDispImagedisp_image
Alternatives
entropy_grayentropy_grayEntropyGrayEntropyGrayentropy_gray
See also
energy_gaborenergy_gaborEnergyGaborEnergyGaborenergy_gabor,
entropy_grayentropy_grayEntropyGrayEntropyGrayentropy_gray
Module
Foundation