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MpatDefine

BoardSupported
Host SystemYes
V4L2Yes
Clarity UHDYes
Concord PoENo
GenTLYes
GevIQYes
GigE VisionYes
IndioNo
Iris GTXYes
Radient eV-CLYes
Rapixo CLYes
Rapixo CoFYes
Rapixo CXPYes
USB3 VisionYes

Add one or more models to, or delete a model from, a Pattern Matching context.

Syntax​

void MpatDefine(
    AIL_ID     ContextPatId,   //out
    AIL_INT64  ModelType,      //in
    AIL_ID     SrcImageBufId,  //in
    AIL_DOUBLE Param1,         //in
    AIL_DOUBLE Param2,         //in
    AIL_DOUBLE Param3,         //in
    AIL_DOUBLE Param4,         //in
    AIL_INT64  ControlFlag     //in
)

Description​

This function allows you to add one or more models at a time to, or delete a model from, a Pattern Matching context. When defining a search model, you are specifying the area of an image to use as a pattern to find within a target image, using MpatFind. When a call to MpatFind is made, all models that are part of the specified context (and that have MpatControl with M_NUMBER set to a value greater than zero) are searched for simultaneously in the target. Note, when a model is added or deleted, the Pattern Matching context must be preprocessed again, using MpatPreprocess.

The search is performed according to the general search settings specified in the Pattern Matching context, as well as the individual model search settings (depending on the M_SEARCH_MODE value specified). Specify both the context and individual model search settings using MpatControl.

When adding a model to the context, a number is assigned to the new model. The context starts numbering the models at 0, and each subsequent model added to the Pattern Matching context is given a sequential index number, in the order that you add the models. When deleting a model, all models with a higher index shift down one.

Parameters​

ContextPatId (out, AIL_ID)​

Specifies the Pattern Matching context to which to add, or from which to delete, the model. The Pattern Matching context must have been previously allocated on the required system using MpatAlloc.

ModelType (in, AIL_INT64)​

Specifies the type of the model to define when adding models to the context, or specifies to delete a model from the Pattern Matching context.

SrcImageBufId (in, AIL_ID)​

Specifies the identifier of the image buffer from which to define the models, or the Pattern Matching context from which to copy a model.

Param1 (in, AIL_DOUBLE)​

Specifies an attribute of the model to add. Its definition is dependent on the model type chosen. When not used, set this parameter to M_DEFAULT.

Param2 (in, AIL_DOUBLE)​

Specifies an attribute of the model to add. Its definition is dependent on the model type chosen. When not used, set this parameter to M_DEFAULT.

Param3 (in, AIL_DOUBLE)​

Specifies an attribute of the model to add. Its definition is dependent on the model type chosen. When not used, set this parameter to M_DEFAULT.

Param4 (in, AIL_DOUBLE)​

Specifies an attribute of the model to add. Its definition is dependent on the model type chosen. When not used, set this parameter to M_DEFAULT.

ControlFlag (in, AIL_INT64)​

Specifies the speed of the allocation or the interpolation mode to use, depending on the model type chosen. When not used, set this parameter to M_DEFAULT.

Parameter Associations​

For defining models to add to specified Pattern Matching context​

To add a model to the Pattern Matching context, the ModelType, Param1, Param2, Param3, and ControlFlag parameters can be set to the following values: Note that any unused parameters should be set to M_DEFAULT. Note, if unused, set SrcImageBufIdto M_NULL.

M_AUTO_MODEL​

Defines one or more models automatically of the specified dimensions from the most-suitable distinct areas found, in the source image. If none are found, no model is allocated and an error is reported. This is useful when you want to perform whole image alignment, for which allocation of a distinct model is essential. It can take several seconds to find the best models (more for large or small images). To be effective, the source image should be a typical target image. You can only define anM_AUTO_MODEL that respect the following condition: (_maxvalue_ <sup>2</sup> * Param3 * Param4)&lt; 2<sup>63</sup> where maxvalue is the maximum pixel value (typically, 255) in the target image and the model. This restriction is imposed to avoid overflows in the internal 64-bit accumulators. The total area of the model must be greater or equal to 4 pixels (Param3 * Param4 >= 4).

ValueDescription
M_DEFAULTSelects models from anywhere in the whole width of the image.
Value >= 0Specifies the expected maximum pixel displacement in the horizontal direction, as an integer.
M_DEFAULTSelects models from anywhere in the whole height of the image.
Value >= 0Specifies the expected maximum pixel displacement in the vertical direction, as an integer.
M_DEFAULT
M_BESTSpecifies that the search should favor high precision over speed. You should typically use this setting if the model source image is small.
M_FAST (default)Specifies that the search should favor speed over high precision. You should typically use this setting if your model source image is large.

M_REGULAR_MODEL​

Defines a regular model, from the specified area, in the source image. You can use this type of model when dealing with images containing a mix of models on an inconsistent background, such as an image of loose nuts and bolts lying on a metal sheet. If the occurrence can appear at an angle, specify the angular range in which it can appear, using MpatControl with M_SEARCH_ANGLE.... If the occurrence is expected to be found always with the same background, use the M_CIRCULAR_OVERSCAN combination constant. To extract the model from a rotated region in the model's source image, pass a source image that is associated with a rectangular region of interest (ROI) at the required angle. You can associate an ROI to your source image using MbufSetRegion. You can only define an M_REGULAR_MODEL model that respects the following condition: (_maxvalue_ <sup>2</sup> * Param3 * Param4)&lt; 2<sup>63</sup>, where maxvalue is the maximum pixel value (typically, 255) in the target image and the model. This restriction is imposed to avoid overflows in the internal 64-bit accumulators. The total area of the model must be greater or equal to 4 pixels (Param3 * Param4 >= 4).

ValueDescription
M_DEFAULTSpecifies that the X-coordinate of the model origin is 0. Alternatively, if the model's source image is associated with an ROI, it specifies to ignore this parameter.
0 <= Value <= ImageSizeXSpecifies the X-coordinate of model origin in the source image, in pixels (as an integer).
M_DEFAULTSpecifies that the Y-coordinate of the model origin is 0. Alternatively, if the model's source image is associated with an ROI, it specifies to ignore this parameter.
0 <= Value <= ImageSizeYSpecifies the Y-coordinate of model origin in the source image, in pixels (as an integer).
M_DEFAULTSpecifies that the width of the model is the distance from the origin of the model to the edge of the image in the X-direction. Alternatively, if the model's source image is associated with an ROI, it specifies to ignore this parameter.
1 <= Value <= ImageSizeXSpecifies the width of the model in the model source image, in pixels (as an integer).
M_DEFAULTSpecifies that the height of the model is the distance from the origin of the model to the edge of the image in the Y-direction. Alternatively, if the model's source image is associated with an ROI, it specifies to ignore this parameter.
1 <= Value <= ImageSizeYSpecifies the height of the model in the model source image, in pixels (as an integer).

Combination Constants — For extracting the circular overscan data​

Optional.

Usage: You can add one of the following values to the above-mentioned values to extract the model as well as a circular area around it.

ValueDescription
M_CIRCULAR_OVERSCANSpecifies that the model is extracted from the source image with the circular overscan data. The circular overscan data is determined by rotating the model, about its center. The circular overscan data of an M_CIRCULAR_OVERSCAN type model is used if you search for an occurrence of the model at an angle. Angular search is fastest when performed with an M_CIRCULAR_OVERSCAN model; however, M_CIRCULAR_OVERSCAN should only be used when the region around the model is consistent, for example, when searching for a chip in the image of an integrated circuit. When preprocessing an M_CIRCULAR_OVERSCAN model for which an angular search range has been specified, a set of models is extracted from rotated versions of the M_CIRCULAR_OVERSCAN model, defining models that would appear upright if the target image were rotated. For this type of model, a larger region than the one defined is extracted from the source image so as to allow creation of models at different angles. The model must not be extracted from a region too close to the edge of the source image. In addition, the M_CIRCULAR_OVERSCAN model should be complex enough so that if models are created from it at the required angles, they are representative of the pattern being sought. For a model defined to include circular overscan data, you cannot define "don't care" regions (MpatMask).

Combination Constants — For use with the auto model context​

Optional.

Usage: You can add one of the following values to the above-mentioned values to set the number of models to allocate from the same image.

ValueDescription
M_MULTIPLE + nAllocates several models from the same source image. Set n to the number of models to define. For example, set ControlFlag to M_BEST+M_MULTIPLE+ 4 to define the four most distinct models available in your model source image. Search models can overlap within the image by half the size of the model (in X and Y).

For deleting the specified model from the Pattern Matching context​

When deleting a model from the specified Pattern Matching context, use the following value: Any unused parameters should be set to M_DEFAULT. Note, if unused, set SrcImageBufIdto M_NULL.

M_DELETE​

Specifies to remove the specified model from the Pattern Matching context, specified using the Param1 parameter. When deleting a model, all models with a higher index shift down one.

ValueDescription
M_ALLSpecifies to delete all models from the Pattern Matching context.
Value >= 0Specifies the index of the model to delete.
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