Image Generator

Functions
XN_C_API XnStatus XN_C_DECL	xnCreateImageGenerator (XnContext *pContext, XnNodeHandle *phImageGenerator, XnNodeQuery *pQuery, XnEnumerationErrors *pErrors)
XN_C_API XnRGB24Pixel *XN_C_DECL	xnGetRGB24ImageMap (XnNodeHandle hInstance)
XN_C_API XnYUV422DoublePixel *XN_C_DECL	xnGetYUV422ImageMap (XnNodeHandle hInstance)
XN_C_API XnGrayscale8Pixel *XN_C_DECL	xnGetGrayscale8ImageMap (XnNodeHandle hInstance)
XN_C_API XnGrayscale16Pixel *XN_C_DECL	xnGetGrayscale16ImageMap (XnNodeHandle hInstance)
XN_C_API XnUInt8 *XN_C_DECL	xnGetImageMap (XnNodeHandle hInstance)
XN_C_API XnBool XN_C_DECL	xnIsPixelFormatSupported (XnNodeHandle hInstance, XnPixelFormat Format)
XN_C_API XnStatus XN_C_DECL	xnSetPixelFormat (XnNodeHandle hInstance, XnPixelFormat Format)
XN_C_API XnPixelFormat XN_C_DECL	xnGetPixelFormat (XnNodeHandle hInstance)
XN_C_API XnStatus XN_C_DECL	xnRegisterToPixelFormatChange (XnNodeHandle hInstance, XnStateChangedHandler handler, void *pCookie, XnCallbackHandle *phCallback)
XN_C_API void XN_C_DECL	xnUnregisterFromPixelFormatChange (XnNodeHandle hInstance, XnCallbackHandle hCallback)
XN_C_API void XN_C_DECL	xnGetImageMetaData (XnNodeHandle hInstance, XnImageMetaData *pMetaData)

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Detailed Description

An Image Generator node is a Map Generator that outputs image maps. It supports all Map Generator functions, and adds additional functions. Image maps may arrive in different pixel formats.

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Function Documentation

XN_C_API XnStatus XN_C_DECL xnCreateImageGenerator	(	XnContext *	pContext,
		XnNodeHandle *	phImageGenerator,
		XnNodeQuery *	pQuery,
		XnEnumerationErrors *	pErrors
	)

Creates an image generator.

Parameters:

pContext	[in] The context in which to create the image generator.
phImageGenerator	[out] A handle to the created image generator.
pQuery	[in] Optional. Can be used to select which image generator to create. If not specified, this function may create any image generator that is available.
pErrors	[in] Optional. If provided, will be filled with information about image generators that could not be created.

XN_C_API XnGrayscale16Pixel* XN_C_DECL xnGetGrayscale16ImageMap

(

XnNodeHandle

hInstance

)

Gets the current Grayscale16 image-map. This map is updated after a call to xnWaitAndUpdateData(). It is assumed that the node is currently in Grayscale16 pixel format.

Parameters:

hInstance

[in] A handle to the instance.

Returns:

NULL if this production node is not an image generator.

XN_C_API XnGrayscale8Pixel* XN_C_DECL xnGetGrayscale8ImageMap

(

XnNodeHandle

hInstance

)

Gets the current Grayscale8 image-map. This map is updated after a call to xnWaitAndUpdateData(). It is assumed that the node is currently in Grayscale8 pixel format.

Parameters:

hInstance

[in] A handle to the instance.

Returns:

NULL if this production node is not an image generator.

XN_C_API XnUInt8* XN_C_DECL xnGetImageMap

(

XnNodeHandle

hInstance

)

Gets the current image-map as a byte buffer.

This map is updated after a call to xnWaitAndUpdateData(). It is highly advised not to use this function. Instead, if you know the format of the image, use xnGetRGB24ImageMap(), xnGetYUV422ImageMap(), xnGetGrayscale8ImageMap() or xnGetGrayscale16ImageMap().

Parameters:

hInstance

[in] A handle to the instance.

Returns:

NULL if this production node is not an image generator.

XN_C_API void XN_C_DECL xnGetImageMetaData	(	XnNodeHandle	hInstance,
		XnImageMetaData *	pMetaData
	)

Gets the current image-map meta data.

Parameters:

hInstance	[in] A handle to the instance.
pMetaData	[in] The struct to be filled.

XN_C_API XnPixelFormat XN_C_DECL xnGetPixelFormat

(

XnNodeHandle

hInstance

)

Gets current pixel format.

Parameters:

hInstance

[in] A handle to the instance.

Returns:

-1 if this production node is not an image generator.

XN_C_API XnRGB24Pixel* XN_C_DECL xnGetRGB24ImageMap

(

XnNodeHandle

hInstance

)

Gets the current RGB24 image-map. This map is updated after a call to xnWaitAndUpdateData(). It is assumed that the node is currently in RGB24 pixel format.

Parameters:

hInstance

[in] A handle to the instance.

Returns:

NULL if this production node is not an image generator.

XN_C_API XnYUV422DoublePixel* XN_C_DECL xnGetYUV422ImageMap

(

XnNodeHandle

hInstance

)

Gets the current YUV422 image-map. This map is updated after a call to xnWaitAndUpdateData(). It is assumed that the node is currently in YUV422 pixel format.

Parameters:

hInstance

[in] A handle to the instance.

Returns:

NULL if this production node is not an image generator.

XN_C_API XnBool XN_C_DECL xnIsPixelFormatSupported	(	XnNodeHandle	hInstance,
		XnPixelFormat	Format
	)

Checks if a specific pixel format is supported.

Parameters:

hInstance	[in] A handle to the instance.
Format	[in] The format to check for.

XN_C_API XnStatus XN_C_DECL xnRegisterToPixelFormatChange	(	XnNodeHandle	hInstance,
		XnStateChangedHandler	handler,
		void *	pCookie,
		XnCallbackHandle *	phCallback
	)

Registers a callback function to pixel format changes.

Parameters:

hInstance	[in] A handle to the instance.
handler	[in] A pointer to a function that will be called when pixel format changes.
pCookie	[in] A user cookie that will be passed to the callback function.
phCallback	[out] Optional. Will be filled with a handle to be passed to xnUnregisterFromPixelFormatChange.

Returns:

XN_STATUS_INVALID_OPERATION if this production node does not support the User Position capability.

XN_C_API XnStatus XN_C_DECL xnSetPixelFormat	(	XnNodeHandle	hInstance,
		XnPixelFormat	Format
	)

Sets the pixel format of the image map.

Parameters:

hInstance	[in] A handle to the instance.
Format	[in] The format to set.

Returns:

XN_STATUS_INVALID_OPERATION if this production node is not an image generator.

XN_C_API void XN_C_DECL xnUnregisterFromPixelFormatChange	(	XnNodeHandle	hInstance,
		XnCallbackHandle	hCallback
	)

Unregisters a callback function which was registered using xnRegisterToPixelFormatChange.

Parameters:

hInstance	[in] A handle to the instance.
hCallback	[in] The handle to the callback returned from xnRegisterToPixelFormatChange.