bandpass_imagebandpass_imageBandpassImageBandpassImagebandpass_image (Operator)

Name

bandpass_imagebandpass_imageBandpassImageBandpassImagebandpass_image — Edge extraction using bandpass filters.

Signature

bandpass_image(Image : ImageBandpass : FilterType : )

Description

bandpass_imagebandpass_imageBandpassImageBandpassImageBandpassImagebandpass_image serves as an edge filter. It applies a linear filter with the following convolution mask to ImageImageImageImageimageimage:

FilterTypeFilterTypeFilterTypeFilterTypefilterTypefilter_type: 'lines'"lines""lines""lines""lines""lines" In contrast to the edge operator sobel_ampsobel_ampSobelAmpSobelAmpSobelAmpsobel_amp this filter detects lines instead of edges, i.e., two closely adjacent edges. 0 -2 -2 -2 0 -2 0 3 0 -2 -2 3 12 3 -2 -2 0 3 0 -2 0 -2 -2 -2 0

At the border of the image the gray values are mirrored. Over- and underflows of gray values are clipped. The resulting images are returned in ImageBandpassImageBandpassImageBandpassImageBandpassimageBandpassimage_bandpass.

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

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

Input images.

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

Bandpass-filtered images.

FilterTypeFilterTypeFilterTypeFilterTypefilterTypefilter_type (input_control) string → (string)

Filter type: currently only 'lines' is supported.

Default value: 'lines' "lines" "lines" "lines" "lines" "lines"

List of values: 'lines'"lines""lines""lines""lines""lines"

Example (C)

bandpass_image(Image,&LineImage,"lines");
threshold(LineImage,&Lines,60.0,255.0);
skeleton(Lines,&ThinLines);

Result

bandpass_imagebandpass_imageBandpassImageBandpassImageBandpassImagebandpass_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>)SetSystem("no_object_result",<Result>)set_system("no_object_result",<Result>). If necessary, an exception is raised.

Possible Successors

thresholdthresholdThresholdThresholdThresholdthreshold, skeletonskeletonSkeletonSkeletonSkeletonskeleton

Alternatives

convol_imageconvol_imageConvolImageConvolImageConvolImageconvol_image, topographic_sketchtopographic_sketchTopographicSketchTopographicSketchTopographicSketchtopographic_sketch, texture_lawstexture_lawsTextureLawsTextureLawsTextureLawstexture_laws

Module

Foundation

Operators