Object: Delay

Detailed Description

Defines the Delay Object interface.

A Delay is an opaque object that contains a manually-controlled, temporally-delayed list of objects.

Typedefs
typedef struct _vx_delay *	vx_delay
	The delay object. This is like a ring buffer of objects that is maintained by the OpenVX implementation. More...

Enumerations
enum	vx_delay_attribute_e {   VX_DELAY_ATTRIBUTE_TYPE = ((( VX_ID_KHRONOS ) << 20) | ( VX_TYPE_DELAY << 8)) + 0x0,   VX_DELAY_ATTRIBUTE_SLOTS = ((( VX_ID_KHRONOS ) << 20) | ( VX_TYPE_DELAY << 8)) + 0x1 }
	The delay attribute list. More...

Functions
vx_status VX_API_CALL	vxAgeDelay (vx_delay delay)
	Ages the internal delay ring by one. This means that once this API is called the reference from index 0 will go to index -1 and so forth until \( -count+1 \) is reached. This last object will become 0. Once the delay has been aged, it updates the reference in any associated nodes. More...
vx_delay VX_API_CALL	vxCreateDelay (vx_context context, vx_reference exemplar, vx_size slots)
	Creates a Delay object. More...
vx_reference VX_API_CALL	vxGetReferenceFromDelay (vx_delay delay, vx_int32 index)
	Retrieves a reference from a delay object. More...
vx_status VX_API_CALL	vxQueryDelay (vx_delay delay, vx_enum attribute, void *ptr, vx_size size)
	Queries a vx_delay object attribute. More...
vx_status VX_API_CALL	vxReleaseDelay (vx_delay *delay)
	Releases a reference to a delay object. The object may not be garbage collected until its total reference count is zero. More...

Typedef Documentation

typedef struct _vx_delay* vx_delay

The delay object. This is like a ring buffer of objects that is maintained by the OpenVX implementation.

See also

vxCreateDelay

Definition at line 210 of file vx_types.h.

Enumeration Type Documentation

enum vx_delay_attribute_e

The delay attribute list.

Enumerator
VX_DELAY_ATTRIBUTE_TYPE	The type of reference contained in the delay. Use a vx_enum parameter.
VX_DELAY_ATTRIBUTE_SLOTS	The number of items in the delay. Use a vx_size parameter.

Definition at line 1146 of file vx_types.h.

Function Documentation

vx_status VX_API_CALL vxQueryDelay	(	vx_delay	delay,
		vx_enum	attribute,
		void *	ptr,
		vx_size	size
	)

Queries a vx_delay object attribute.

Parameters

[in]	delay	A pointer to a delay object.
[in]	attribute	The attribute to query. Use a vx_delay_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.

vx_status VX_API_CALL vxReleaseDelay

(

vx_delay *

delay

)

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

Parameters

[in]

delay

The pointer to the delay to release.

Postcondition

After returning from this function the reference is zeroed.

Returns

A vx_status_e enumeration.

Return values

VX_SUCCESS	No errors.
VX_ERROR_INVALID_REFERENCE	If delay is not a vx_delay.

vx_delay VX_API_CALL vxCreateDelay	(	vx_context	context,
		vx_reference	exemplar,
		vx_size	slots
	)

Creates a Delay object.

This function uses a subset of the attributes defining the metadata of the exemplar, ignoring the object. It does not alter the exemplar or keep or release the reference to the exemplar. For the definition of supported attributes see vxSetMetaFormatAttribute.

Parameters

[in]	context	The reference to the system context.
[in]	exemplar	The exemplar object.
[in]	slots	The number of reference in the delay.

Returns

A delay reference vx_delay. Any possible errors preventing a successful creation should be checked using vxGetStatus.

vx_reference VX_API_CALL vxGetReferenceFromDelay	(	vx_delay	delay,
		vx_int32	index
	)

Retrieves a reference from a delay object.

Parameters

[in]	delay	The reference to the delay object.
[in]	index	An index into the delay from which to extract the reference.

Returns

vx_reference

Note

The delay index is in the range \( [-count+1,0] \). 0 is always the current object.

A reference from a delay object must not be given to its associated release API (e.g. vxReleaseImage). Use the vxReleaseDelay only.

vx_status VX_API_CALL vxAgeDelay

(

vx_delay

delay

)

Ages the internal delay ring by one. This means that once this API is called the reference from index 0 will go to index -1 and so forth until \( -count+1 \) is reached. This last object will become 0. Once the delay has been aged, it updates the reference in any associated nodes.

Parameters

[in]

delay

Returns

A vx_status_e enumeration.

Return values

VX_SUCCESS	Delay was aged.
VX_ERROR_INVALID_REFERENCE	The value passed as delay was not a vx_delay.