Select regions based on gray value features.
The operator select_gray has a number of regions (Regions) as input. For each of these regions the features (Features) are calculated. If each (Operation = 'and') or at least one (Operation = 'or') of the calculated features is within the limits determined by the parameter, the region is transferred (duplicated) into the output. The parameter Image contains an image which returns the gray values for calculating the features.
Condition: Min[i] <= Features[i](Regions,Image) <= Max[i]Possble values for Features:
'area' Gray value volume of region
(see area_center_gray)
'row' Row index of the center of gravity
(see area_center_gray)
'column' Column index of the center of gravity
(see area_center_gray)
'ra' Major axis of equivallent ellipse
(see elliptic_axis_gray)
'rb' Minor axis of equivallent ellipse
(see elliptic_axis_gray)
'phi' Orientation of equivallent ellipse
(see elliptic_axis_gray)
'min' Minimum gray value (see min_max_gray)
'max' Maximum gray value (see min_max_gray)
'mean' Mean gray value (see intensity)
'deviation' Deviation of gray values (see intensity)
'plane_deviation' Deviation from the approximating plane
(see plane_deviation)
'anisotropy' Anisotropy (see entropy_gray)
'entropy' Entropy (see entropy_gray)
'fuzzy_entropy' Fuzzy entropie of region (see fuzzy_entropy,
with a fuzzy function from Apar=0 to Cpar=255)
'fuzzy_perimeter' Fuzzy perimeter of region (see fuzzy_perimeter,
with a fuzzy function from Apar=0 to Cpar=255)
'moments_row' Mixed moments along a row
(see moments_gray_plane)
'moments_column' Mixed moments along a column
(see moments_gray_plane)
'alpha' Approximating plane, parameter Alpha
(see moments_gray_plane)
'beta' Approximating plane, parameter Beta
(see moments_gray_plane)
If only one feature is used the value of Operation is meaningless. Several features are processed in the order in which they are entered.
|
Regions (input_object) |
region-array -> object |
| Regions to be examined. | |
|
Image (input_object) |
image -> object : byte / direction / cyclic / int1 / int2 / uint2 / int4 / real |
| Gray value image. | |
|
SelectedRegions (output_object) |
region-array -> object |
| Regions having features within the limits. | |
|
Features (input_control) |
string(-array) -> string |
| Names of the features. | |
| Default value: 'mean' | |
| List of values: 'area', 'row', 'column', 'ra', 'rb', 'phi', 'min', 'max', 'mean', 'deviation', 'plane_deviation', 'anisotropy', 'entropy', 'fuzzy_entropy', 'fuzzy_perimeter', 'moments_row', 'moments_column', 'alpha', 'beta' | |
|
Operation (input_control) |
string -> string |
| Logical connection of features. | |
| Default value: 'and' | |
| List of values: 'and', 'or' | |
|
Min (input_control) |
number(-array) -> real / integer |
| Lower limit(s) of features. | |
| Default value: 128.0 | |
| Suggested values: 0.5, 1.0, 10.0, 20.0, 50.0, 128.0, 255.0, 1000.0 | |
|
Max (input_control) |
number(-array) -> real / integer |
| Upper limit(s) of features. | |
| Default value: 255.0 | |
| Suggested values: 0.5, 1.0, 10.0, 20.0, 50.0, 128.0, 255.0, 1000.0 | |
If F is the area of the region and N the number of features the runtime complexity is O(F * N).
The operator select_gray returns the value 2 (H_MSG_TRUE) if the input image has the defined gray values and the parameters are correct. The behavior in case of empty input (no input images available) is set via the operator set_system(::'no_object_result',<Result>:), the behavior in case of empty region is set via set_system(::'empty_region_result',<Result>:). If necessary an exception handling is raised.
select_gray is reentrant and automatically parallelized (on tuple level).
connection, mean_image, entropy_image, sobel_amp, median_separate
select_shape, select_gray, shape_trans, reduce_domain, count_obj
deviation_image, entropy_gray, intensity, mean_image, min_max_gray, select_obj
Image filters
