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MpatAlloc

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

Allocate a Pattern Matching context.

Syntax

AIL_ID MpatAlloc(
AIL_ID SysId, //in
AIL_INT64 ContextType, //in
AIL_INT64 ControlFlag, //in
AIL_ID * ContextPatIdPtr //out
)

Description

This function allocates a Pattern Matching context on the specified system. A Pattern Matching context contains all the information necessary to perform anMpatFind operation on a target image, including global search settings and one or more models.

Define search models and add to them to the Pattern Matching context usingMpatDefine. Note that you must add at least one model to the context.

You can adjust the Pattern Matching context settings using MpatControl. To inquire the Pattern Matching context settings, use MpatInquire.

When the Pattern Matching context is no longer required, release it usingMpatFreeunless M_UNIQUE_ID was specified during allocation; if M_UNIQUE_ID was specified, the smart identifier manages the Pattern Matching context's lifetime and you must not manually free it.

Parameters

SysId (in, AIL_ID)

Specifies the system on which to allocate the Pattern Matching context.

For specifying the system identifier

ValueDescription
M_DEFAULT_HOSTSpecifies the default Host system of the current Aurora Imaging Library application.
System identifierSpecifies a valid system identifier, which you have allocated using the MsysAlloc function.

ContextType (in, AIL_INT64)

Specifies the type of Pattern Matching context. The parameter must be set to the following:

For the types of Pattern Matching context

ValueDescription
M_DEFAULT
M_NORMALIZED (default)Specifies a normalized grayscale correlation (NGC) Pattern Matching context.

ControlFlag (in, AIL_INT64)

Reserved for future expansion. This parameter must be set to M_DEFAULT.

ContextPatIdPtr *(out, AIL_ID)

Specifies the address of the variable in which to write the Pattern Matching context identifier or specifies the data type that the function should use to return the Pattern Matching context identifier.

For retrieving the identifier or specifying how to return it

ValueDescription
M_NULLSpecifies that you will use this function's return value to obtain the identifier of the allocated Pattern Matching context; in this case, a standard Aurora Imaging Library identifier of type AIL_ID is returned.
M_UNIQUE_IDSpecifies that you will use this function's return value to obtain the identifier of the allocated Pattern Matching context; in this case, an Aurora Imaging Library smart identifier of type _AIL_UNIQUE_PAT_ID_is returned instead of a standard Aurora Imaging Library identifier.This setting is only available when using C++11 (or later).An Aurora Imaging Library smart identifier manages the lifespan of the Aurora Imaging Library object it owns (similar to a std::unique_ptr). Note, you can use an Aurora Imaging Library smart identifier as though it were a standard Aurora Imaging Library identifier, except that you cannot use it to manually free the Pattern Matching context (it is freed automatically). For more information, see Aurora Imaging Library smart identifiers.
Address in which to write the identifierSpecifies the address of an AIL_ID in which to write the identifier of the allocated Pattern Matching context.

If allocation fails, M_NULL is written as the identifier. |

Return Value

Type: AIL_ID

The returned value is the Pattern Matching context identifier either as a standard identifier (AIL_ID) or a smart identifier (AIL_UNIQUE_PAT_ID). If allocation fails, M_NULL is returned (or nullptr ifM_UNIQUE_ID was specified).

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