The Public Threshold API. More...

Typedefs
typedef struct Threshold *	vx_threshold
	The Threshold Object. A thresholding object contains the types and limit values of the thresholding required.

Enumerations
enum	vx_threshold_type_e { VX_THRESHOLD_TYPE_BINARY = VX_ENUM_BASE(VX_ID_KHRONOS, VX_ENUM_THRESHOLD_TYPE) + 0x0 , VX_THRESHOLD_TYPE_RANGE = VX_ENUM_BASE(VX_ID_KHRONOS, VX_ENUM_THRESHOLD_TYPE) + 0x1 }
	The Threshold types. More...

enum	vx_threshold_attribute_e { VX_THRESHOLD_TYPE = VX_ATTRIBUTE_BASE(VX_ID_KHRONOS, VX_TYPE_THRESHOLD) + 0x0 , VX_THRESHOLD_INPUT_FORMAT = VX_ATTRIBUTE_BASE(VX_ID_KHRONOS, VX_TYPE_THRESHOLD) + 0x7 , VX_THRESHOLD_OUTPUT_FORMAT = VX_ATTRIBUTE_BASE(VX_ID_KHRONOS, VX_TYPE_THRESHOLD) + 0x8 }
	The threshold attributes. More...

Functions
VX_API_ENTRY vx_threshold VX_API_CALL	vxCreateThresholdForImage (vx_context context, vx_enum thresh_type, vx_df_image input_format, vx_df_image output_format)
	Creates a threshold object and returns a reference to it.

VX_API_ENTRY vx_threshold VX_API_CALL	vxCreateVirtualThresholdForImage (vx_graph graph, vx_enum thresh_type, vx_df_image input_format, vx_df_image output_format)
	Creates an opaque reference to a threshold object without direct user access.

VX_API_ENTRY vx_status VX_API_CALL	vxCopyThresholdValue (vx_threshold thresh, vx_pixel_value_t *value_ptr, vx_enum usage, vx_enum user_mem_type)
	Allows the application to copy the thresholding value from/into a threshold object with type `VX_THRESHOLD_TYPE_BINARY`.

VX_API_ENTRY vx_status VX_API_CALL	vxCopyThresholdRange (vx_threshold thresh, vx_pixel_value_t lower_value_ptr, vx_pixel_value_t upper_value_ptr, vx_enum usage, vx_enum user_mem_type)
	Allows the application to copy thresholding values from/into a threshold object with type `VX_THRESHOLD_TYPE_RANGE`.

VX_API_ENTRY vx_status VX_API_CALL	vxCopyThresholdOutput (vx_threshold thresh, vx_pixel_value_t true_value_ptr, vx_pixel_value_t false_value_ptr, vx_enum usage, vx_enum user_mem_type)
	Allows the application to copy the true and false output values from/into a threshold object.

VX_API_ENTRY vx_status VX_API_CALL	vxReleaseThreshold (vx_threshold *thresh)
	Releases a reference to a threshold object. The object may not be garbage collected until its total reference count is zero.

VX_API_ENTRY vx_status VX_API_CALL	vxSetThresholdAttribute (vx_threshold thresh, vx_enum attribute, const void *ptr, vx_size size)
	Sets attributes on the threshold object.

VX_API_ENTRY vx_status VX_API_CALL	vxQueryThreshold (vx_threshold thresh, vx_enum attribute, void *ptr, vx_size size)
	Queries an attribute on the threshold object.

Detailed Description

The Public Threshold API.

Typedef Documentation

◆ vx_threshold

typedef struct Threshold* vx_threshold

#include <vx_types.h>

The Threshold Object. A thresholding object contains the types and limit values of the thresholding required.

Enumeration Type Documentation

◆ vx_threshold_attribute_e

enum vx_threshold_attribute_e

#include <vx_types.h>

The threshold attributes.

Enumerator
VX_THRESHOLD_TYPE	The value type of the threshold. Read-only. Use a `vx_enum` parameter. Will contain a `vx_threshold_type_e`.
VX_THRESHOLD_INPUT_FORMAT	The input image format the threshold was created for. Read-only. Use a `vx_enum` parameter. Will contain a `vx_df_image_e`.
VX_THRESHOLD_OUTPUT_FORMAT	The output image format the threshold was created for. Read-only. Use a `vx_enum` parameter. Will contain a `vx_df_image_e`.

◆ vx_threshold_type_e

enum vx_threshold_type_e

#include <vx_types.h>

The Threshold types.

Enumerator
VX_THRESHOLD_TYPE_BINARY	A threshold with only 1 value.
VX_THRESHOLD_TYPE_RANGE	A threshold with 2 values (upper/lower). Use with Canny Edge Detection.

Function Documentation

◆ vxCopyThresholdOutput()

VX_API_ENTRY vx_status VX_API_CALL vxCopyThresholdOutput	(	vx_threshold	thresh,
		vx_pixel_value_t *	true_value_ptr,
		vx_pixel_value_t *	false_value_ptr,
		vx_enum	usage,
		vx_enum	user_mem_type )

#include <vx_api.h>

Allows the application to copy the true and false output values from/into a threshold object.

Parameters

[in]	thresh	The reference to the threshold object that is the source or the destination of the copy.
[in,out]	true_value_ptr	The address of the memory location where to store the true output value if the copy was requested in read mode, or from where to get the true output value to store into the threshold object if the copy was requested in write mode.
[in,out]	false_value_ptr	The address of the memory location where to store the false output value if the copy was requested in read mode, or from where to get the false output value to store into the threshold object if the copy was requested in write mode.
[in]	usage	This declares the effect of the copy with regard to the threshold object using the `vx_accessor_e` enumeration. Only `VX_READ_ONLY` and `VX_WRITE_ONLY` are supported: `VX_READ_ONLY` means that true and false output values are copied from the threshold object into the user memory. After the copy, only the field of (true_value_ptr) and (false_value_ptr) unions that corresponds to the output image format of the threshold object is meaningful. `VX_WRITE_ONLY` means the field of the (true_value_ptr) and (false_value_ptr) unions corresponding to the output format of the threshold object is copied into the threshold object.
[in]	user_mem_type	A `vx_memory_type_e` enumeration that specifies the type of the memory referenced by `true_value_ptr` and `false_value_ptr`.

Returns: A vx_status_e enumeration.

Return values

VX_ERROR_INVALID_REFERENCE	The threshold reference is not actually a threshold reference.
VX_ERROR_INVALID_PARAMETERS	An other parameter is incorrect.

◆ vxCopyThresholdRange()

VX_API_ENTRY vx_status VX_API_CALL vxCopyThresholdRange	(	vx_threshold	thresh,
		vx_pixel_value_t *	lower_value_ptr,
		vx_pixel_value_t *	upper_value_ptr,
		vx_enum	usage,
		vx_enum	user_mem_type )

#include <vx_api.h>

Allows the application to copy thresholding values from/into a threshold object with type VX_THRESHOLD_TYPE_RANGE.

Parameters

[in]	thresh	The reference to the threshold object that is the source or the destination of the copy.
[in,out]	lower_value_ptr	The address of the memory location where to store the lower thresholding value if the copy was requested in read mode, or from where to get the lower thresholding value to store into the threshold object if the copy was requested in write mode.
[in,out]	upper_value_ptr	The address of the memory location where to store the upper thresholding value if the copy was requested in read mode, or from where to get the upper thresholding value to store into the threshold object if the copy was requested in write mode.
[in]	usage	This declares the effect of the copy with regard to the threshold object using the `vx_accessor_e` enumeration. Only `VX_READ_ONLY` and `VX_WRITE_ONLY` are supported: `VX_READ_ONLY` means that thresholding values are copied from the threshold object into the user memory. After the copy, only the field of (lower_value_ptr) and (upper_value_ptr) unions that corresponds to the input image format of the threshold object is meaningful. `VX_WRITE_ONLY` means the field of the (lower_value_ptr) and (upper_value_ptr) unions corresponding to the input format of the threshold object is copied into the threshold object.
[in]	user_mem_type	A `vx_memory_type_e` enumeration that specifies the type of the memory referenced by `lower_value_ptr` and `upper_value_ptr`.

Returns: A vx_status_e enumeration.

Return values

VX_ERROR_INVALID_REFERENCE	The threshold reference is not actually a threshold reference.
VX_ERROR_NOT_COMPATIBLE	The threshold object doesn't have type `VX_THRESHOLD_TYPE_RANGE`
VX_ERROR_INVALID_PARAMETERS	An other parameter is incorrect.

◆ vxCopyThresholdValue()

VX_API_ENTRY vx_status VX_API_CALL vxCopyThresholdValue	(	vx_threshold	thresh,
		vx_pixel_value_t *	value_ptr,
		vx_enum	usage,
		vx_enum	user_mem_type )

#include <vx_api.h>

Allows the application to copy the thresholding value from/into a threshold object with type VX_THRESHOLD_TYPE_BINARY.

Parameters

[in]	thresh	The reference to the threshold object that is the source or the destination of the copy.
[in,out]	value_ptr	The address of the memory location where to store the thresholding value if the copy was requested in read mode, or from where to get the thresholding value to store into the threshold object if the copy was requested in write mode.
[in]	usage	This declares the effect of the copy with regard to the threshold object using the `vx_accessor_e` enumeration. Only `VX_READ_ONLY` and `VX_WRITE_ONLY` are supported: `VX_READ_ONLY` means that the thresholding value is copied from the threshold object into the user memory. After the copy, only the field of the (value_ptr) union that corresponds to the input image format of the threshold object is meaningful. `VX_WRITE_ONLY` means the field of the (value_ptr) union corresponding to the input format of the threshold object is copied into the threshold object.
[in]	user_mem_type	A `vx_memory_type_e` enumeration that specifies the type of the memory referenced by `value_ptr`.

Returns: A vx_status_e enumeration.

Return values

VX_ERROR_INVALID_REFERENCE	The threshold reference is not actually a threshold reference.
VX_ERROR_NOT_COMPATIBLE	The threshold object doesn't have type `VX_THRESHOLD_TYPE_BINARY`
VX_ERROR_INVALID_PARAMETERS	An other parameter is incorrect.

◆ vxCreateThresholdForImage()

VX_API_ENTRY vx_threshold VX_API_CALL vxCreateThresholdForImage	(	vx_context	context,
		vx_enum	thresh_type,
		vx_df_image	input_format,
		vx_df_image	output_format )

#include <vx_api.h>

Creates a threshold object and returns a reference to it.

The threshold object defines the parameters of a thresholding operation to an input image, that generates an output image that can have a different format. The thresholding 'false' or 'true' output values are specified per pixel channels of the output format and can be modified with vxCopyThresholdOutput. The default 'false' output value of pixels channels should be 0, and the default 'true' value should be non-zero. For standard image formats, default output pixel values are defined as following:

VX_DF_IMAGE_RGB : false={0, 0, 0}, true={255,255,255}
VX_DF_IMAGE_RGBX : false={0, 0, 0, 0}, true={255,255,255,255}
VX_DF_IMAGE_NV12 : false={0, 0, 0}, true={255,255,255}
VX_DF_IMAGE_NV21 : false={0, 0, 0}, true={255,255,255}
VX_DF_IMAGE_UYVY : false={0, 0, 0}, true={255,255,255}
VX_DF_IMAGE_YUYV : false={0, 0, 0}, true={255,255,255}
VX_DF_IMAGE_IYUV : false={0, 0, 0}, true={255,255,255}
VX_DF_IMAGE_YUV4 : false={0, 0, 0}, true={255,255,255}
VX_DF_IMAGE_U8 : false=0, true=0xFF
VX_DF_IMAGE_S16 : false=0, true=-1
VX_DF_IMAGE_U16 : false=0, true=0xFFFF
VX_DF_IMAGE_S32 : false=0, true=-1

VX_DF_IMAGE_U32 : false=0, true=0xFFFFFFFF

Parameters

[in]	context	The reference to the context in which the object is created.
[in]	thresh_type	The type of thresholding operation.
[in]	input_format	The format of images that will be used as input of the thresholding operation.
[in]	output_format	The format of images that will be generated by the thresholding operation.

Returns: A threshold reference vx_threshold. Any possible errors preventing a successful creation should be checked using vxGetStatus.

◆ vxCreateVirtualThresholdForImage()

VX_API_ENTRY vx_threshold VX_API_CALL vxCreateVirtualThresholdForImage	(	vx_graph	graph,
		vx_enum	thresh_type,
		vx_df_image	input_format,
		vx_df_image	output_format )

#include <vx_api.h>

Creates an opaque reference to a threshold object without direct user access.

Parameters

[in]	graph	The reference to the parent graph.
[in]	thresh_type	The type of thresholding operation.
[in]	input_format	The format of images that will be used as input of the thresholding operation.
[in]	output_format	The format of images that will be generated by the thresholding operation.

See also: vxCreateThresholdForImage

Returns: A threshold reference vx_threshold. Any possible errors preventing a successful creation should be checked using vxGetStatus.

◆ vxQueryThreshold()

VX_API_ENTRY vx_status VX_API_CALL vxQueryThreshold	(	vx_threshold	thresh,
		vx_enum	attribute,
		void *	ptr,
		vx_size	size )

#include <vx_api.h>

Queries an attribute on the threshold object.

Parameters

[in]	thresh	The threshold object to set.
[in]	attribute	The attribute to query. Use a `vx_threshold_attribute_e` enumeration.
[out]	ptr	The location at which to store the resulting value.
[in]	size	The size of the container to which ptr points.

Returns: A vx_status_e enumeration.

Return values

VX_SUCCESS	No errors; any other value indicates failure.
VX_ERROR_INVALID_REFERENCE	thresh is not a valid `vx_threshold` reference.

◆ vxReleaseThreshold()

VX_API_ENTRY vx_status VX_API_CALL vxReleaseThreshold ( vx_threshold * thresh )

#include <vx_api.h>

Releases a reference to a threshold object. The object may not be garbage collected until its total reference count is zero.

Parameters

[in] thresh The pointer to the threshold to release.

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

Returns: A vx_status_e enumeration.

Return values

VX_SUCCESS	No errors; any other value indicates failure.
VX_ERROR_INVALID_REFERENCE	thresh is not a valid `vx_threshold` reference.

Examples: bubble_pop.cpp, and skinToneDetector.cpp.

◆ vxSetThresholdAttribute()

VX_API_ENTRY vx_status VX_API_CALL vxSetThresholdAttribute	(	vx_threshold	thresh,
		vx_enum	attribute,
		const void *	ptr,
		vx_size	size )

#include <vx_api.h>

Sets attributes on the threshold object.

Parameters

[in]	thresh	The threshold object to set.
[in]	attribute	The attribute to modify. Use a `vx_threshold_attribute_e` enumeration.
[in]	ptr	The pointer to the value to which to set the attribute.
[in]	size	The size of the data pointed to by ptr.

Returns: A vx_status_e enumeration.

Return values

VX_SUCCESS	No errors; any other value indicates failure.
VX_ERROR_INVALID_REFERENCE	thresh is not a valid `vx_threshold` reference.

Examples: bubble_pop.cpp, canny.cpp, and skinToneDetector.cpp.

Typedefs

Enumerations

Functions

Detailed Description

Typedef Documentation

◆ vx_threshold

Enumeration Type Documentation

◆ vx_threshold_attribute_e

◆ vx_threshold_type_e

Function Documentation

◆ vxCopyThresholdOutput()

◆ vxCopyThresholdRange()

◆ vxCopyThresholdValue()

◆ vxCreateThresholdForImage()

◆ vxCreateVirtualThresholdForImage()

◆ vxQueryThreshold()

◆ vxReleaseThreshold()

◆ vxSetThresholdAttribute()