robertsrobertsRobertsrobertsRobertsRoberts (Operator)

Name

robertsrobertsRobertsrobertsRobertsRoberts — Detect edges using the Roberts filter.

Signature

roberts(Image : ImageRoberts : FilterType : )

Description

robertsrobertsRobertsrobertsRobertsRoberts calculates the first derivative of an image and is used as an edge operator. If the following mask describes a part of the image,

                        A               B

                        C               D

the different filter types are defined as follows:

   'roberts_max'     max(| A - D |,| B - C |)
   'gradient_max'    max(| A + B - (C + D)|,| A + C - (B + D)|)
   'gradient_sum'    |A + B - (C + D)| + |A + C - (B + D)|

If an overflow occurs the result is clipped. The result of the operator is stored at the pixel with the coordinates of "D".

Parallelization

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

ImageImageImageImageImageimage (input_object) (multichannel-)image(-array) → object (byte / int2 / uint2)

Input image.

ImageRobertsImageRobertsImageRobertsImageRobertsImageRobertsimageRoberts (output_object) (multichannel-)image(-array) → object (byte / int2 / uint2)

Roberts-filtered result images.

FilterTypeFilterTypeFilterTypeFilterTypeFilterTypefilterType (input_control) string → (string)

Filter type.

Default value: 'gradient_sum' "gradient_sum" "gradient_sum" "gradient_sum" "gradient_sum" "gradient_sum"

List of values: 'gradient_max'"gradient_max""gradient_max""gradient_max""gradient_max""gradient_max", 'gradient_sum'"gradient_sum""gradient_sum""gradient_sum""gradient_sum""gradient_sum", 'roberts_max'"roberts_max""roberts_max""roberts_max""roberts_max""roberts_max"

Example (HDevelop)

read_image(Image,'fabrik')
roberts(Image,Roberts,'roberts_max')
threshold(Roberts,Margin,128,255)

Example (C)

read_image(&Image,"fabrik");
roberts(Image,&Roberts,"roberts_max");
threshold(Roberts,&Margin,128.0,255.0);

Example (HDevelop)

read_image(Image,'fabrik')
roberts(Image,Roberts,'roberts_max')
threshold(Roberts,Margin,128,255)

Example (HDevelop)

read_image(Image,'fabrik')
roberts(Image,Roberts,'roberts_max')
threshold(Roberts,Margin,128,255)

Example (HDevelop)

read_image(Image,'fabrik')
roberts(Image,Roberts,'roberts_max')
threshold(Roberts,Margin,128,255)

Example (HDevelop)

read_image(Image,'fabrik')
roberts(Image,Roberts,'roberts_max')
threshold(Roberts,Margin,128,255)

Result

robertsrobertsRobertsrobertsRobertsRoberts returns 2 (H_MSG_TRUE) if all parameters are correct. If the input is empty the behaviour can be set via set_system('no_object_result',<Result>)set_system("no_object_result",<Result>)SetSystem("no_object_result",<Result>)set_system("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>). If necessary, an exception is raised.

edges_imageedges_imageEdgesImageedges_imageEdgesImageEdgesImage, sobel_ampsobel_ampSobelAmpsobel_ampSobelAmpSobelAmp, frei_ampfrei_ampFreiAmpfrei_ampFreiAmpFreiAmp, kirsch_ampkirsch_ampKirschAmpkirsch_ampKirschAmpKirschAmp, prewitt_ampprewitt_ampPrewittAmpprewitt_ampPrewittAmpPrewittAmp

Module

Foundation

Operators

robertsrobertsRobertsrobertsRobertsRoberts (Operator)

Name

Signature

Description

Parallelization

Parameters

Example (HDevelop)

Example (C)

Example (HDevelop)

Example (HDevelop)

Example (HDevelop)

Example (HDevelop)

Result

Possible Predecessors

Possible Successors

Alternatives

See also

Module