An abstract representation of a 2D image pyramid. More...

Data Structures
struct	VPIPyramidData
	Stores the pyramid contents. More...

Macros
#define	VPI_MAX_PYRAMID_LEVEL_COUNT (10)
	Maximum number of pyramid levels.

Typedefs
typedef struct VPIPyramidImpl *	VPIPyramid
	A handle to an image pyramid.

Functions
VPIStatus	vpiPyramidCreate (int32_t width, int32_t height, VPIImageFormat fmt, int32_t numLevels, float scale, uint32_t flags, VPIPyramid *pyr)
	Create an empty image pyramid instance with the specified flags. More...

void	vpiPyramidDestroy (VPIPyramid pyr)
	Destroy an image pyramid instance as well as all resources it owns. More...

VPIStatus	vpiPyramidGetFlags (VPIPyramid pyr, uint32_t *flags)
	Returns the flags associated with the pyramid. More...

VPIStatus	vpiPyramidGetFormat (VPIPyramid pyr, VPIImageFormat *fmt)
	Returns the image format of the pyramid levels. More...

VPIStatus	vpiPyramidGetNumLevels (VPIPyramid pyr, int32_t *numLevels)
	Get the image pyramid level count. More...

VPIStatus	vpiPyramidGetSize (VPIPyramid pyr, int32_t outSize, int32_t outWidth, int32_t outHeight)
	Get the image width and height in pixels (for all levels at once). More...

VPIStatus	vpiPyramidGetScale (VPIPyramid pyr, float *scale)
	Returns the scale factor of the pyramid levels. More...

VPIStatus	vpiPyramidLock (VPIPyramid pyr, VPILockMode lock, VPIPyramidData *out)
	Acquires the lock on a pyramid object and returns pointers to each level of the pyramid. More...

VPIStatus	vpiPyramidUnlock (VPIPyramid pyr)
	Releases the lock on a image pyramid object. More...

VPIStatus	vpiImageCreatePyramidLevelWrapper (VPIPyramid pyr, int32_t level, VPIImage *img)
	Creates an image that wraps one pyramid level. More...

Detailed Description

An abstract representation of a 2D image pyramid.

2D image pyramid containers are created by calling vpiPyramidCreate to allocate and initialize an empty (zeroed) VPIPyramid object. The memory for the image pyramid data is allocated and managed by VPI.

Image formats match the ones supported by image container. The pyramid is not necessarily dyadic. The scale between levels is defined in the constructor.

Parameters such as levels, scale, width, height and image format are immutable and specified at the construction time. The internal memory layout is also backend-specific. More importantly, efficient exchange of image pyramid data between different hardware blocks might force the implementation to allocate the memory in multiple memory pools (e.g. dGPU and system DRAM). In some scenarios (to optimize performance and memory use), it might be beneficial to constrain the internal allocation policy to support only a particular set of backends.

The set of vpiPyramidLock / vpiPyramidUnlock calls allows the user to read from/write to the image data from the host. These functions are non-blocking and oblivious to the device command queue, so it's up to the user to make sure that all pending operations using this image pyramid as input or output are finished. Also, depending on the enabled backends lock/unlock * operation might be time-consuming and, for example, involve copying data over PCIe bus for dGPUs.

Data Structure Documentation

◆ VPIPyramidData

struct VPIPyramidData

Stores the pyramid contents.

Every level is represented by an entire VPIImageData. There are numLevels levels, and they can be accessed from levels[0] to levels[numLevels-1].

Definition at line 111 of file Pyramid.h.

Collaboration diagram for VPIPyramidData:

Data Fields
VPIImageData	levels[VPI_MAX_PYRAMID_LEVEL_COUNT]	Scale factor of resolution between two adjecent levels. Contents of every pyramid level. Only the first numLevels levels has valid data.
int32_t	numLevels	Number of levels (i.e. height) of the pyramid.
float	scale

Function Documentation

◆ vpiImageCreatePyramidLevelWrapper()

VPIStatus vpiImageCreatePyramidLevelWrapper	(	VPIPyramid	pyr,
		int32_t	level,
		VPIImage *	img
	)

#include <vpi/Pyramid.h>

Creates an image that wraps one pyramid level.

The created image doesn't own its contents. Destroying the pyramid while there are images wrapping its levels leads to undefined behavior. If image wraps the base pyramid level, locking the pyramid will also lock the image. Once the image isn't needed anymore, call vpiImageDestroy to free resources.

Parameters

[in]	pyr	The pyramid whose level will be wrapped.
[in]	level	Pyramid level to wrap.
[out]	img	Pointer to an image handle that will hold the created image.

Returns: VPI_SUCCESS if image was created successfully, or any other VPIStatus error code in case of error.

◆ vpiPyramidCreate()

VPIStatus vpiPyramidCreate	(	int32_t	width,
		int32_t	height,
		VPIImageFormat	fmt,
		int32_t	numLevels,
		float	scale,
		uint32_t	flags,
		VPIPyramid *	pyr
	)

#include <vpi/Pyramid.h>

Create an empty image pyramid instance with the specified flags.

Pyramid data is zeroed.

Parameters

[in]	width,height	Dimensions of the finest pyramid level.
[in]	numLevels	Number of levels.
[in]	scale	Downscale factor from one level and the next.
[in]	fmt	Image format of each level.
[in]	flags	Pyramid flags. Here it can be specified in what backends the pyramid can be used by or-ing together VPIBackend flags. Set flags to 0 to enable it in all backends supported by the active VPI context.
[out]	pyr	Pointer to memory that will receive the created pyramid handle.

Returns: an error code on failure else VPI_SUCCESS

◆ vpiPyramidDestroy()

void vpiPyramidDestroy ( VPIPyramid pyr )

#include <vpi/Pyramid.h>

Destroy an image pyramid instance as well as all resources it owns.

Parameters

[in] pyr pyramid handle

◆ vpiPyramidGetFlags()

VPIStatus vpiPyramidGetFlags	(	VPIPyramid	pyr,
		uint32_t *	flags
	)

#include <vpi/Pyramid.h>

Returns the flags associated with the pyramid.

Parameters

[in]	pyr	pyramid handle
[out]	flags	pointer to where the flags will be written.

Returns: VPI_SUCCESS if function was able to return the flags, or any other VPIStatus code in case of error.

◆ vpiPyramidGetFormat()

VPIStatus vpiPyramidGetFormat	(	VPIPyramid	pyr,
		VPIImageFormat *	fmt
	)

#include <vpi/Pyramid.h>

Returns the image format of the pyramid levels.

Parameters

[in]	pyr	pyramid handle
[out]	fmt	pointer to where the image format will be written.

Returns: VPI_SUCCESS if function was able to return the flags, or any other VPIStatus code in case of error.

◆ vpiPyramidGetNumLevels()

VPIStatus vpiPyramidGetNumLevels	(	VPIPyramid	pyr,
		int32_t *	numLevels
	)

#include <vpi/Pyramid.h>

Get the image pyramid level count.

Parameters

[in]	pyr	an image pyramid handle
[out]	numLevels	a pointer to a variable which will be set to the number of levels of the image pyramid

Returns: an error code on failure else VPI_SUCCESS

◆ vpiPyramidGetScale()

VPIStatus vpiPyramidGetScale	(	VPIPyramid	pyr,
		float *	scale
	)

#include <vpi/Pyramid.h>

Returns the scale factor of the pyramid levels.

Parameters

[in]	pyr	pyramid handle
[out]	scale	pointer to where the scale will be written.

Returns: VPI_SUCCESS if function was able to return the scale, or any other VPIStatus code in case of error.

◆ vpiPyramidGetSize()

VPIStatus vpiPyramidGetSize	(	VPIPyramid	pyr,
		int32_t	outSize,
		int32_t *	outWidth,
		int32_t *	outHeight
	)

#include <vpi/Pyramid.h>

Get the image width and height in pixels (for all levels at once).

Parameters

[in]	pyr	an image pyramid handle
[in]	outSize	size of the output arrays, in elements.
[out]	outWidth,outHeight	Pointers to a C array which will be filled widths and heights (respectively) of all image pyramid levels. If any of them is NULL, the corresponding data isn't returned.

Returns: an error code on failure else VPI_SUCCESS

◆ vpiPyramidLock()

VPIStatus vpiPyramidLock	(	VPIPyramid	pyr,
		VPILockMode	lock,
		VPIPyramidData *	out
	)

#include <vpi/Pyramid.h>

Acquires the lock on a pyramid object and returns pointers to each level of the pyramid.

Depending on the internal image representation, as well as the actual location in memory, this function might have a significant performance overhead (format conversion, layout conversion, device-to-host memory copy).

Parameters

[in]	pyr	an image pyramid handle
[in]	lock	lock mode
[out]	out	a pointer to a structure that will receive the pyramid data to be accessed by host. If it's NULL, the pyramid will still be locked. This is useful to make sure wrapped image is updated.

Returns: an error code on failure else VPI_SUCCESS

◆ vpiPyramidUnlock()

VPIStatus vpiPyramidUnlock ( VPIPyramid pyr )

#include <vpi/Pyramid.h>

Releases the lock on a image pyramid object.

This function might have a significant performance overhead (format conversion, layout conversion, host-to-device memory copy).

Parameters

[in] pyr an image pyramid handle

Returns: an error code on failure else VPI_SUCCESS

VPI - Vision Programming Interface

1.2 Release

Data Structures

Macros

Typedefs

Functions

Detailed Description

Data Structure Documentation

◆ VPIPyramidData

Function Documentation

◆ vpiImageCreatePyramidLevelWrapper()

◆ vpiPyramidCreate()

◆ vpiPyramidDestroy()

◆ vpiPyramidGetFlags()

◆ vpiPyramidGetFormat()

◆ vpiPyramidGetNumLevels()

◆ vpiPyramidGetScale()

◆ vpiPyramidGetSize()

◆ vpiPyramidLock()

◆ vpiPyramidUnlock()