Select regions based on gray value features.
The operator select_grey__ 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]Possible values for Features:
'mean' mean gray value (see: intensity__) 'deviation' standard deviation of gray values (see: intensity__) 'min' minimum gray value (see: min_max__) 'max' maximum gray value (see: min_max__) 'entropy' entropy (see: entropy2__) 'anisotropy' anisotropy (see: entropy2__)
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 / int2 / 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: 'mean', 'min', 'max', 'deviation', 'entropy', 'anisotropy' |
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_grey__ returns the value 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 is raised.
connection, mean__, entropy1__, sobel_amp, median_separate
select_shape, select_grey__, shape_trans, reduce_domain, count_obj
deviation__, entropy2__, intensity__, mean__, min_max__, select_obj