create_component_modelcreate_component_modelCreateComponentModelCreateComponentModel (Operator)

Name

create_component_modelcreate_component_modelCreateComponentModelCreateComponentModel — Prepare a component model for matching based on explicitly specified components and relations.

Signature

Description

create_component_modelcreate_component_modelCreateComponentModelCreateComponentModelCreateComponentModel prepares patterns, which are passed in the form of a model image ModelImageModelImageModelImageModelImagemodelImage and several regions ComponentRegionsComponentRegionsComponentRegionsComponentRegionscomponentRegions, as a component model for matching. The output parameter ComponentModelIDComponentModelIDComponentModelIDComponentModelIDcomponentModelID is a handle for this model, which is used in subsequent calls to find_component_modelfind_component_modelFindComponentModelFindComponentModelFindComponentModel. In contrast to create_trained_component_modelcreate_trained_component_modelCreateTrainedComponentModelCreateTrainedComponentModelCreateTrainedComponentModel, no preceding training with train_model_componentstrain_model_componentsTrainModelComponentsTrainModelComponentsTrainModelComponents needs to be performed before calling create_component_modelcreate_component_modelCreateComponentModelCreateComponentModelCreateComponentModel.

Each of the regions passed in ComponentRegionsComponentRegionsComponentRegionsComponentRegionscomponentRegions describes a separate model component. Later, the index of a component region in ComponentRegionsComponentRegionsComponentRegionsComponentRegionscomponentRegions is used to denote the model component. The reference point of a component is the center of gravity of its associated region, which is passed in ComponentRegionsComponentRegionsComponentRegionsComponentRegionscomponentRegions. It can be calculated by calling area_centerarea_centerAreaCenterAreaCenterAreaCenter.

The relative movements (relations) of the model components can be set by passing VariationRowVariationRowVariationRowVariationRowvariationRow, VariationColumnVariationColumnVariationColumnVariationColumnvariationColumn, and VariationAngleVariationAngleVariationAngleVariationAnglevariationAngle. Because directly passing the relations is complicated, instead of the relations the variations of the model components are passed. The variations describe the movements of the components independently from each other relative to their poses in the model image ModelImageModelImageModelImageModelImagemodelImage. The parameters VariationRowVariationRowVariationRowVariationRowvariationRow and VariationColumnVariationColumnVariationColumnVariationColumnvariationColumn describe the movement of the components in row and column direction by and , respectively. The parameter VariationAngleVariationAngleVariationAngleVariationAnglevariationAngle describes the angle variation of the component by . Based on these values, the relations are automatically computed. The three parameters must either contain one element, in which case the parameter is used for all model components, or must contain the same number of elements as ComponentRegionsComponentRegionsComponentRegionsComponentRegionscomponentRegions, in which case each parameter element refers to the corresponding model component in ComponentRegionsComponentRegionsComponentRegionsComponentRegionscomponentRegions.

The parameters AngleStartAngleStartAngleStartAngleStartangleStart and AngleExtentAngleExtentAngleExtentAngleExtentangleExtent determine the range of possible rotations of the component model in an image.

Internally, a separate shape model is built for each model component (see create_shape_modelcreate_shape_modelCreateShapeModelCreateShapeModelCreateShapeModel). Therefore, the parameters ContrastLowCompContrastLowCompContrastLowCompContrastLowCompcontrastLowComp, ContrastHighCompContrastHighCompContrastHighCompContrastHighCompcontrastHighComp, MinSizeCompMinSizeCompMinSizeCompMinSizeCompminSizeComp, MinContrastCompMinContrastCompMinContrastCompMinContrastCompminContrastComp, MinScoreCompMinScoreCompMinScoreCompMinScoreCompminScoreComp, NumLevelsCompNumLevelsCompNumLevelsCompNumLevelsCompnumLevelsComp, AngleStepCompAngleStepCompAngleStepCompAngleStepCompangleStepComp, OptimizationCompOptimizationCompOptimizationCompOptimizationCompoptimizationComp, MetricCompMetricCompMetricCompMetricCompmetricComp, and PregenerationCompPregenerationCompPregenerationCompPregenerationComppregenerationComp correspond to the parameters of create_shape_modelcreate_shape_modelCreateShapeModelCreateShapeModelCreateShapeModel, with the following differences: First, in the parameter ContrastContrastContrastContrastcontrast of create_shape_modelcreate_shape_modelCreateShapeModelCreateShapeModelCreateShapeModel the upper as well as the lower threshold for the hysteresis threshold method can be passed. Additionally, a third value, which suppresses small connected contour regions, can be passed. In contrast, the operator create_component_modelcreate_component_modelCreateComponentModelCreateComponentModelCreateComponentModel offers three separate parameters ContrastHighCompContrastHighCompContrastHighCompContrastHighCompcontrastHighComp, ContrastLowCompContrastLowCompContrastLowCompContrastLowCompcontrastLowComp, and MinScoreCompMinScoreCompMinScoreCompMinScoreCompminScoreComp in order to set these three values. Consequently, also the automatic computation of the contrast threshold(s) is different. If both hysteresis threshold should be automatically determined, both ContrastLowCompContrastLowCompContrastLowCompContrastLowCompcontrastLowComp and ContrastHighCompContrastHighCompContrastHighCompContrastHighCompcontrastHighComp must be set to 'auto'"auto""auto""auto""auto". In contrast, if only one threshold value should be determined, ContrastLowCompContrastLowCompContrastLowCompContrastLowCompcontrastLowComp must be set to 'auto'"auto""auto""auto""auto" while ContrastHighCompContrastHighCompContrastHighCompContrastHighCompcontrastHighComp must be set to an arbitrary value different from 'auto'"auto""auto""auto""auto". Secondly, the parameter OptimizationOptimizationOptimizationOptimizationoptimization of create_shape_modelcreate_shape_modelCreateShapeModelCreateShapeModelCreateShapeModel provides the possibility to reduce the number of model points as well as the possibility to completely pregenerate the shape model. In contrast, the operator create_trained_component_modelcreate_trained_component_modelCreateTrainedComponentModelCreateTrainedComponentModelCreateTrainedComponentModel uses a separate parameter PregenerationCompPregenerationCompPregenerationCompPregenerationComppregenerationComp in order to decide whether the shape models should be completely pregenerated or not. A third difference concerning the parameter MinScoreCompMinScoreCompMinScoreCompMinScoreCompminScoreComp should be noted. When using the shape-based matching, this parameter needs not be passed when preparing the shape model using create_shape_modelcreate_shape_modelCreateShapeModelCreateShapeModelCreateShapeModel, but only during the search using find_shape_modelfind_shape_modelFindShapeModelFindShapeModelFindShapeModel. In contrast, when preparing the component model it is favorable to analyze rotational symmetries of the model components and similarities between the model components. However, this analysis only leads to meaningful results if the value for MinScoreCompMinScoreCompMinScoreCompMinScoreCompminScoreComp that is used during the search (see find_component_modelfind_component_modelFindComponentModelFindComponentModelFindComponentModel) is already approximately known.

In addition to the parameters ContrastLowCompContrastLowCompContrastLowCompContrastLowCompcontrastLowComp, ContrastHighCompContrastHighCompContrastHighCompContrastHighCompcontrastHighComp, and MinSizeCompMinSizeCompMinSizeCompMinSizeCompminSizeComp also the parameters MinContrastCompMinContrastCompMinContrastCompMinContrastCompminContrastComp, NumLevelsCompNumLevelsCompNumLevelsCompNumLevelsCompnumLevelsComp, AngleStepCompAngleStepCompAngleStepCompAngleStepCompangleStepComp, and OptimizationCompOptimizationCompOptimizationCompOptimizationCompoptimizationComp can be automatically determined by passing 'auto'"auto""auto""auto""auto" for the respective parameters.

All component-specific input parameters (parameter names terminate with the suffix Comp) must either contain one element, in which case the parameter is used for all model components, or must contain the same number of elements as the number of regions in ComponentRegionsComponentRegionsComponentRegionsComponentRegionscomponentRegions, in which case each parameter element refers to the corresponding element in ComponentRegionsComponentRegionsComponentRegionsComponentRegionscomponentRegions.

In addition to the individual shape models, the component model also contains information about the way the single model components must be searched relative to each other using find_component_modelfind_component_modelFindComponentModelFindComponentModelFindComponentModel in order to minimize the computation time of the search. For this, the components are represented in a tree structure. First, the component that stands at the root of this search tree (root component) is searched. Then, the remaining components are searched relative to the pose of their predecessor in the search tree.

The root component can be passed as an input parameter of find_component_modelfind_component_modelFindComponentModelFindComponentModelFindComponentModel during the search. To what extent a model component is suited to act as the root component depends on several factors. In principle, a model component that can be found in the image with a high probability should be chosen. Therefore, a component that is sometimes occluded to a high degree or that is missing in some cases is not well suited to act as the root component. Additionally, the computation time that is associated with the root component during the search can serve as a criterion. A ranking of the model components that is based on the latter criterion is returned in RootRankingRootRankingRootRankingRootRankingrootRanking. In this parameter the indices of the model components are sorted in descending order according to their associated search time, i.e., RootRankingRootRankingRootRankingRootRankingrootRanking[0] contains the index of the model component that, chosen as root component, allows the fastest search. Note that the ranking returned in RootRankingRootRankingRootRankingRootRankingrootRanking represents only a coarse estimation. Furthermore, the calculation of the root ranking assumes that the image size as well as the value of the system parameter 'border_shape_models'"border_shape_models""border_shape_models""border_shape_models""border_shape_models" are identical when calling create_component_modelcreate_component_modelCreateComponentModelCreateComponentModelCreateComponentModel and find_component_modelfind_component_modelFindComponentModelFindComponentModelFindComponentModel.

Execution Information

• Multithreading type: reentrant (runs in parallel with non-exclusive operators).
• Multithreading scope: global (may be called from any thread).
• Processed without parallelization.

This operator returns a handle. Note that the state of an instance of this handle type may be changed by specific operators even though the handle is used as an input parameter by those operators.

Parameters

Example (HDevelop)

* Read the model image.
read_image (ModelImage, 'model_image.tif')
* Describe the model components.
gen_rectangle2 (ComponentRegions, 318, 109, -1.62, 34, 19)
gen_rectangle2 (Rectangle2, 342, 238, -1.63, 32, 17)
gen_rectangle2 (Rectangle3, 355, 505, 1.41, 25, 17)
concat_obj (ComponentRegions, Rectangle2, ComponentRegions)
concat_obj (ComponentRegions, Rectangle3, ComponentRegions)
* Create the component model by explicitly specifying the relations.
create_component_model (ModelImage, ComponentRegions, 20, 20, rad(25), 0, \
                        rad(360), 15, 40, 15, 10, 0.8, 'auto', 'auto', \
                        'none', 'use_polarity', 'false', ComponentModelID, \
                        RootRanking)
* Find the component model in a run-time image.
read_image (SearchImage, 'search_image.tif')
find_component_model (SearchImage, ComponentModelID, RootRanking, 0, \
                      rad(360), 0.5, 0, 0.5, 'stop_search', \
                      'search_from_best', 'none', 0.8, 'least_squares', 0, \
                      0.8, ModelStart, ModelEnd, Score, RowComp, \
                      ColumnComp, AngleComp, ScoreComp, ModelComp)

Result

If the parameters are valid, the operator create_component_modelcreate_component_modelCreateComponentModelCreateComponentModelCreateComponentModel returns the value 2 (H_MSG_TRUE). If necessary an exception is raised.

Possible Predecessors

draw_regiondraw_regionDrawRegionDrawRegionDrawRegion, concat_objconcat_objConcatObjConcatObjConcatObj

Possible Successors

find_component_modelfind_component_modelFindComponentModelFindComponentModelFindComponentModel

Alternatives

create_trained_component_modelcreate_trained_component_modelCreateTrainedComponentModelCreateTrainedComponentModelCreateTrainedComponentModel

See also

create_shape_modelcreate_shape_modelCreateShapeModelCreateShapeModelCreateShapeModel, find_shape_modelfind_shape_modelFindShapeModelFindShapeModelFindShapeModel

Module

Matching