cv::cuda::HostMem Class Reference

Class with reference counting wrapping special memory type allocation functions from CUDA. More...

#include <cuda.hpp>

Public Types
enum	AllocType { PAGE_LOCKED = 1 , SHARED = 2 , WRITE_COMBINED = 4 }

Public Member Functions
CV_WRAP	HostMem (HostMem::AllocType alloc_type=HostMem::AllocType::PAGE_LOCKED)
	HostMem (const HostMem &m)
CV_WRAP	HostMem (int rows, int cols, int type, HostMem::AllocType alloc_type=HostMem::AllocType::PAGE_LOCKED)
CV_WRAP	HostMem (Size size, int type, HostMem::AllocType alloc_type=HostMem::AllocType::PAGE_LOCKED)
CV_WRAP	HostMem (InputArray arr, HostMem::AllocType alloc_type=HostMem::AllocType::PAGE_LOCKED)
	creates from host memory with coping data More...
	~HostMem ()
HostMem &	operator= (const HostMem &m)
CV_WRAP void	swap (HostMem &b)
	swaps with other smart pointer More...
CV_WRAP HostMem	clone () const
	returns deep copy of the matrix, i.e. the data is copied More...
CV_WRAP void	create (int rows, int cols, int type)
	allocates new matrix data unless the matrix already has specified size and type. More...
void	create (Size size, int type)
CV_WRAP HostMem	reshape (int cn, int rows=0) const
void	release ()
	decrements reference counter and released memory if needed. More...
CV_WRAP Mat	createMatHeader () const
	returns matrix header with disabled reference counting for HostMem data. More...
GpuMat	createGpuMatHeader () const
	Maps CPU memory to GPU address space and creates the cuda::GpuMat header without reference counting for it. More...
CV_WRAP bool	isContinuous () const
CV_WRAP size_t	elemSize () const
CV_WRAP size_t	elemSize1 () const
CV_WRAP int	type () const
CV_WRAP int	depth () const
CV_WRAP int	channels () const
CV_WRAP size_t	step1 () const
CV_WRAP Size	size () const
CV_WRAP bool	empty () const

Static Public Member Functions
static MatAllocator *	getAllocator (HostMem::AllocType alloc_type=HostMem::AllocType::PAGE_LOCKED)

Public Attributes
int	flags
int	rows
int	cols
CV_PROP size_t	step
uchar *	data
int *	refcount
uchar *	datastart
const uchar *	dataend
AllocType	alloc_type

Detailed Description

Class with reference counting wrapping special memory type allocation functions from CUDA.

Its interface is also Mat-like but with additional memory type parameters.

• PAGE_LOCKED sets a page locked memory type used commonly for fast and asynchronous uploading/downloading data from/to GPU.
• SHARED specifies a zero copy memory allocation that enables mapping the host memory to GPU address space, if supported.
• WRITE_COMBINED sets the write combined buffer that is not cached by CPU. Such buffers are used to supply GPU with data when GPU only reads it. The advantage is a better CPU cache utilization.

Note

Allocation size of such memory types is usually limited. For more details, see CUDA 2.2 Pinned Memory APIs document or CUDA C Programming Guide.

Member Enumeration Documentation

AllocType

enum cv::cuda::HostMem::AllocType

Enumerator
PAGE_LOCKED
SHARED
WRITE_COMBINED

Constructor & Destructor Documentation

HostMem() [1/5]

CV_WRAP cv::cuda::HostMem::HostMem ( HostMem::AllocType  alloc_type = HostMem::AllocType::PAGE_LOCKED )

explicit

HostMem() [2/5]

cv::cuda::HostMem::HostMem

(

const HostMem &

m

)

HostMem() [3/5]

CV_WRAP cv::cuda::HostMem::HostMem	(	int	rows,
		int	cols,
		int	type,
		HostMem::AllocType	alloc_type = HostMem::AllocType::PAGE_LOCKED
	)

HostMem() [4/5]

CV_WRAP cv::cuda::HostMem::HostMem	(	Size	size,
		int	type,
		HostMem::AllocType	alloc_type = HostMem::AllocType::PAGE_LOCKED
	)

HostMem() [5/5]

CV_WRAP cv::cuda::HostMem::HostMem ( InputArray  arr, HostMem::AllocType  alloc_type = HostMem::AllocType::PAGE_LOCKED  )

explicit

creates from host memory with coping data

~HostMem()

cv::cuda::HostMem::~HostMem

(

)

Member Function Documentation

channels()

CV_WRAP int cv::cuda::HostMem::channels

(

)

const

clone()

CV_WRAP HostMem cv::cuda::HostMem::clone

(

)

const

returns deep copy of the matrix, i.e. the data is copied

create() [1/2]

CV_WRAP void cv::cuda::HostMem::create	(	int	rows,
		int	cols,
		int	type
	)

allocates new matrix data unless the matrix already has specified size and type.

create() [2/2]

void cv::cuda::HostMem::create	(	Size	size,
		int	type
	)

createGpuMatHeader()

GpuMat cv::cuda::HostMem::createGpuMatHeader

(

)

const

Maps CPU memory to GPU address space and creates the cuda::GpuMat header without reference counting for it.

This can be done only if memory was allocated with the SHARED flag and if it is supported by the hardware. Laptops often share video and CPU memory, so address spaces can be mapped, which eliminates an extra copy.

createMatHeader()

CV_WRAP Mat cv::cuda::HostMem::createMatHeader

(

)

const

returns matrix header with disabled reference counting for HostMem data.

depth()

CV_WRAP int cv::cuda::HostMem::depth

(

)

const

elemSize()

CV_WRAP size_t cv::cuda::HostMem::elemSize

(

)

const

elemSize1()

CV_WRAP size_t cv::cuda::HostMem::elemSize1

(

)

const

empty()

CV_WRAP bool cv::cuda::HostMem::empty

(

)

const

getAllocator()

static MatAllocator* cv::cuda::HostMem::getAllocator ( HostMem::AllocType  alloc_type = HostMem::AllocType::PAGE_LOCKED )

static

isContinuous()

CV_WRAP bool cv::cuda::HostMem::isContinuous

(

)

const

operator=()

HostMem& cv::cuda::HostMem::operator=

(

const HostMem &

m

)

release()

void cv::cuda::HostMem::release

(

)

decrements reference counter and released memory if needed.

reshape()

CV_WRAP HostMem cv::cuda::HostMem::reshape	(	int	cn,
		int	rows = 0
	)		const

creates alternative HostMem header for the same data, with different number of channels and/or different number of rows

size()

CV_WRAP Size cv::cuda::HostMem::size

(

)

const

step1()

CV_WRAP size_t cv::cuda::HostMem::step1

(

)

const

swap()

CV_WRAP void cv::cuda::HostMem::swap

(

HostMem &

b

)

swaps with other smart pointer

type()

CV_WRAP int cv::cuda::HostMem::type

(

)

const

Member Data Documentation

alloc_type

AllocType cv::cuda::HostMem::alloc_type

cols

int cv::cuda::HostMem::cols

data

uchar* cv::cuda::HostMem::data

dataend

const uchar* cv::cuda::HostMem::dataend

datastart

uchar* cv::cuda::HostMem::datastart

flags

int cv::cuda::HostMem::flags

refcount

int* cv::cuda::HostMem::refcount

rows

int cv::cuda::HostMem::rows

step

CV_PROP size_t cv::cuda::HostMem::step

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The documentation for this class was generated from the following file:

• build/release/_deps/opencv-src/include/opencv4/opencv2/core/cuda.hpp