Detailed Description

Defines the Look-Up Table Interface.

A lookup table is an array that simplifies run-time computation by replacing computation with a simpler array indexing operation.

Modules
	The Look-Up Table (LUT) attribute list.
	The Look-Up Table (LUT) attribute list.

Typedefs
typedef struct _vx_lut *	vx_lut
	The Look-Up Table (LUT) Object.

Functions
vx_status VX_API_CALL	vxCopyLUT (vx_lut lut, void *user_ptr, vx_enum usage, vx_enum user_mem_type)
	Allows the application to copy from/into a LUT object [R00953]. More...

vx_lut VX_API_CALL	vxCreateLUT (vx_context context, vx_enum data_type, vx_size count)
	Creates LUT object of a given type [R00933]. The value of `VX_LUT_OFFSET` is equal to 0 for data_type = `VX_TYPE_UINT8`, and (vx_uint32)(count/2) for `VX_TYPE_INT16` [R00934]. More...

vx_status VX_API_CALL	vxMapLUT (vx_lut lut, vx_map_id map_id, void *ptr, vx_enum usage, vx_enum mem_type, vx_bitfield flags)
	Allows the application to get direct access to LUT object [R00962]. More...

vx_status VX_API_CALL	vxQueryLUT (vx_lut lut, vx_enum attribute, void *ptr, vx_size size)
	Queries attributes from a LUT [R00947]. More...

vx_status VX_API_CALL	vxReleaseLUT (vx_lut *lut)
	Releases a reference to a LUT object [R00943]. The object may not be garbage collected until its total reference count is zero. More...

vx_status VX_API_CALL	vxUnmapLUT (vx_lut lut, vx_map_id map_id)
	Unmap and commit potential changes to LUT object that was previously mapped [R00977]. Unmapping a LUT invalidates the memory location from which the LUT data could be accessed by the application. Accessing this memory location after the unmap function completes has implementation-dependent behavior. More...

Function Documentation

◆ vxCreateLUT()

vx_lut VX_API_CALL vxCreateLUT	(	vx_context	context,
		vx_enum	data_type,
		vx_size	count
	)

Creates LUT object of a given type [R00933]. The value of VX_LUT_OFFSET is equal to 0 for data_type = VX_TYPE_UINT8, and (vx_uint32)(count/2) for VX_TYPE_INT16 [R00934].

Parameters

[in]	context	The reference to the context [R00935].
[in]	data_type	The type of data stored in the LUT [R00936]. The data_type can be `VX_TYPE_UINT8` or `VX_TYPE_INT16` [R00937].
[in]	count	The number of entries desired [R00938].

Note: If data_type is VX_TYPE_UINT8, count should be less than or equal to 256 [R00939]. If data_type is VX_TYPE_INT16, count should be less than or equal to 65536 [R00940].

Returns: An LUT reference vx_lut [R00941]. Any possible errors preventing a successful creation should be checked using vxGetStatus [R00942].

◆ vxReleaseLUT()

vx_status VX_API_CALL vxReleaseLUT ( vx_lut * lut )

Releases a reference to a LUT object [R00943]. The object may not be garbage collected until its total reference count is zero.

Parameters

[in] lut The pointer to the LUT to release [R00944].

Postcondition: After returning from this function the reference is zeroed [R00945].

Returns: A The vx_status Constants value.

Return values

VX_SUCCESS	No errors; any other value indicates failure [R00946].
VX_ERROR_INVALID_REFERENCE	lut is not a valid `vx_lut` reference.

◆ vxQueryLUT()

vx_status VX_API_CALL vxQueryLUT	(	vx_lut	lut,
		vx_enum	attribute,
		void *	ptr,
		vx_size	size
	)

Queries attributes from a LUT [R00947].

Parameters

[in]	lut	The LUT to query [R00948].
[in]	attribute	The attribute to query. Use a `The Look-Up Table (LUT) attribute list.` value [R00949].
[out]	ptr	The location at which to store the resulting value [R00950].
[in]	size	The size in bytes of the container to which ptr points [R00951].

Returns: A The vx_status Constants value.

Return values

VX_SUCCESS	No errors; any other value indicates failure [R00952].
VX_ERROR_INVALID_REFERENCE	lut is not a valid `vx_lut` reference.

◆ vxCopyLUT()

vx_status VX_API_CALL vxCopyLUT	(	vx_lut	lut,
		void *	user_ptr,
		vx_enum	usage,
		vx_enum	user_mem_type
	)

Allows the application to copy from/into a LUT object [R00953].

Parameters

[in]	lut	The reference to the LUT object that is the source or the destination of the copy [R00954].
[in]	user_ptr	The address of the memory location where to store the requested data if the copy was requested in read mode, or from where to get the data to store into the LUT object if the copy was requested in write mode [R00955]. In the user memory, the LUT is represented as a array with elements of the type corresponding to `VX_LUT_TYPE`, and with a number of elements equal to the value returned via `VX_LUT_COUNT` [R00956]. The accessible memory must be large enough to contain this array: accessible memory in bytes >= sizeof(data_element) * count.
[in]	usage	This declares the effect of the copy with regard to the LUT object using the `The memory accessor hint flags.` value. Only `VX_READ_ONLY` and `VX_WRITE_ONLY` are supported [R00957]: `VX_READ_ONLY` means that data are copied from the LUT object into the user memory [R00958]. `VX_WRITE_ONLY` means that data are copied into the LUT object from the user memory [R00959].
[in]	user_mem_type	A `Memory import type constants.` value that specifies the memory type of the memory referenced by the user_addr [R00960].

Returns: A The vx_status Constants value.

Return values

VX_SUCCESS	No errors; any other value indicates failure [R00961].
VX_ERROR_INVALID_REFERENCE	lut is not a valid `vx_lut` reference.
VX_ERROR_INVALID_PARAMETERS	An other parameter is incorrect.

◆ vxMapLUT()

vx_status VX_API_CALL vxMapLUT	(	vx_lut	lut,
		vx_map_id *	map_id,
		void **	ptr,
		vx_enum	usage,
		vx_enum	mem_type,
		vx_bitfield	flags
	)

Allows the application to get direct access to LUT object [R00962].

Parameters

[in]	lut	The reference to the LUT object to map [R00963].
[out]	map_id	The address of a `vx_map_id` variable where the function returns a map identifier [R00964]. (map_id) must eventually be provided as the map_id parameter of a call to `vxUnmapLUT` [R00965*].
[out]	ptr	The address of a pointer that the function sets to the address where the requested data can be accessed [R00966]. In the mapped memory area, the LUT data are structured as an array with elements of the type corresponding to `VX_LUT_TYPE`, with a number of elements equal to the value returned via `VX_LUT_COUNT` [R00967]. Accessing the memory out of the bound of this array is forbidden and has implementation-dependent behavior. The returned (ptr) address is valid between the call to the function and the corresponding call to `vxUnmapLUT` [R00968*].
[in]	usage	This declares the access mode for the LUT [R00969]. `VX_READ_ONLY`: after the function call, the content of the memory location pointed by (ptr) contains the LUT data [R00970]. Writing into this memory location is forbidden and its behavior is implementation-dependent. `VX_READ_AND_WRITE`: after the function call, the content of the memory location pointed by (ptr) contains the LUT data [R00971]; writing into this memory is allowed only for the location of entries and will result in a modification of the affected entries in the LUT object once the LUT is unmapped [R00972]. `VX_WRITE_ONLY`: after the function call, the data at memory location pointed by (*ptr) is implementation-dependent; writing each entry of LUT is required prior to unmapping. Entries not written by the application before unmap will become implementation-dependent after unmap, even if they were well defined before map.
[in]	mem_type	A `Memory import type constants.` value that specifies the type of the memory where the LUT is requested to be mapped [R00973].
[in]	flags	An integer that allows passing options to the map operation [R00974]. Use 0 for this option [R00975].

Returns: A The vx_status Constants value.

Return values

VX_SUCCESS	No errors; any other value indicates failure [R00976].
VX_ERROR_INVALID_REFERENCE	lut is not a valid `vx_lut` reference.
VX_ERROR_INVALID_PARAMETERS	An other parameter is incorrect.

Postcondition: vxUnmapLUT with same (*map_id) value.

◆ vxUnmapLUT()

vx_status VX_API_CALL vxUnmapLUT	(	vx_lut	lut,
		vx_map_id	map_id
	)

Unmap and commit potential changes to LUT object that was previously mapped [R00977]. Unmapping a LUT invalidates the memory location from which the LUT data could be accessed by the application. Accessing this memory location after the unmap function completes has implementation-dependent behavior.

Parameters

[in]	lut	The reference to the LUT object to unmap [R00978].
[out]	map_id	The unique map identifier that was returned when calling `vxMapLUT` [R00979].

Returns: A The vx_status Constants value.

Return values

VX_SUCCESS	No errors; any other value indicates failure [R00980].
VX_ERROR_INVALID_REFERENCE	lut is not a valid `vx_lut` reference.
VX_ERROR_INVALID_PARAMETERS	An other parameter is incorrect.

Precondition: vxMapLUT returning the same map_id value [R00981].

Detailed Description

Modules

Typedefs

Functions

Function Documentation

◆ vxCreateLUT()

◆ vxReleaseLUT()

◆ vxQueryLUT()

◆ vxCopyLUT()

◆ vxMapLUT()

◆ vxUnmapLUT()