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MbufGetHookInfo

BoardSupported
Host SystemPartial
V4L2Partial
Clarity UHDPartial
Concord PoENo
GenTLPartial
GevIQPartial
GigE VisionPartial
IndioNo
Iris GTXPartial
Radient eV-CLPartial
Rapixo CLPartial
Rapixo CoFPartial
Rapixo CXPPartial
USB3 VisionPartial

Get information about a hook event.

Syntax

AIL_INT MbufGetHookInfo(
AIL_ID EventId, //in
AIL_INT64 InfoType, //in
void * UserVarPtr //out
)

Description

This function allows you to get information about the event that caused the hook-handler function to be called. MbufGetHookInfo should only be called within the scope of a buffer or container hook-handler function (see MbufHookFunction).

Parameters

EventId (in, AIL_ID)

Specifies the buffer or container event identifier received by the hook-handler function (see MbufHookFunction).

InfoType (in, AIL_INT64)

Specifies the event type and the type of information about the event to return.

UserVarPtr *(out, void)

Specifies the address in which to write the requested information.

Parameter Associations

For the event type


M_GC_FEATURE_CHANGE_NAME

Board availability: GenTL, V4L2

Retrieves the name of the GenICam feature that changed. This information type is only available ifMbufGetHookInfo is used from a function hooked to GenTL feature change events using MbufHookFunction with M_FEATURE_CHANGE.

ValueDescription
ValueSpecifies the feature name.

M_MODIFIED_BUFFER

Retrieves information about a modified buffer or container type of event. This event occurs if the hook-handler function was hooked using MbufHookFunction with M_MODIFIED_BUFFER.


M_OBJECT_ID

Retrieves the identifier of the container that was modified. This event occurs if the hook-handler function was hooked using MbufHookFunction with M_LAYOUT_MODIFIED.

ValueDescription
Container identifierSpecifies the identifier of the container that was modified.

Combination Constants — For the modified buffer type of event

Essential.

Usage: You must add one of the following values to the above-mentioned values to set the type of information to return.

M_BUFFER_ID

Retrieves the Aurora Imaging Library identifier of the modified buffer or container.

M_GRAB_TIME_STAMP

Board availability: Iris GTX, Radient eV-CL, Rapixo CL, Rapixo CXP, Rapixo CoF

Inquires the time when Aurora Imaging Library finished grabbing into the buffer, expressed in seconds. Typically, this will be in seconds since the Host computer was started. This can be used to see if a frame has been missed since the last time stamp.

M_MOVED

Returns whether the buffer modification event was triggered by a move operation performed by MbufChildMove; that is, the buffer is a child buffer and its X/Y offset was changed.

ValueDescription
M_NOSpecifies that the buffer modification event was not triggered by a move operation.
M_YESSpecifies that the buffer modification event was triggered by a move operation.

M_REGION_OFFSET_X

Retrieves the X-offset of the modified region (of the buffer).

M_REGION_OFFSET_Y

Retrieves the Y-offset of the modified region (of the buffer).

M_REGION_SIZE_X

Retrieves the width of the modified region (of the buffer).

M_REGION_SIZE_Y

Retrieves the height of the modified region (of the buffer).

M_RESIZED

Returns whether the buffer modification event was triggered by a resize operation performed by MbufChildMove; that is; the buffer is a child buffer and its XY-size was changed.

ValueDescription
M_NOSpecifies that the buffer modification event was not triggered by a resize operation.
M_YESSpecifies that the buffer modification event was triggered by a resize operation.

Combination Constants — For getting the string size

Optional.

Usage: You can add one of the following values to the above-mentioned values to get the string's length.

Board availability: GenTL, V4L2

M_STRING_SIZE

Retrieves the length of the string, including the terminating null character ("\0").

Return Value

Type: AIL_INT

The returned value is M_NULL if successful. If the operation fails, a non-null (!M_NULL) value is returned.

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