Image Locking and Unlocking

Detailed Description

Locking and unlocking provides acces to the image surfaces.

Data Structures
struct	NvMediaImageSurface
	Image surface descriptor used by NvMediaImageLock. More...
struct	NvMediaImageSurfaceMap
	Image surface map descriptor used by NvMediaImageLock. More...

Enumerations
enum	NvMediaImageLockAccess {   NVMEDIA_IMAGE_ACCESS_READ = (1 << 0),   NVMEDIA_IMAGE_ACCESS_WRITE = (1 << 1),   NVMEDIA_IMAGE_ACCESS_READ_WRITE = (NVMEDIA_IMAGE_ACCESS_READ | NVMEDIA_IMAGE_ACCESS_WRITE) }
	Image lock access types. More...

Functions
NvMediaStatus	NvMediaImageLock (NvMediaImage *image, uint32_t lockAccessType, NvMediaImageSurfaceMap *surfaceMap)
	Locks an image and returns the associated mapped pointers pointing to the image surface data. More...
void	NvMediaImageUnlock (NvMediaImage *image)
	Unlocks an image. More...

Enumeration Type Documentation

enum NvMediaImageLockAccess

Image lock access types.

Enumerator
NVMEDIA_IMAGE_ACCESS_READ	Read access.
NVMEDIA_IMAGE_ACCESS_WRITE	Write access.
NVMEDIA_IMAGE_ACCESS_READ_WRITE	Read/Write access.

Definition at line 201 of file nvmedia_image.h.

Function Documentation

NvMediaStatus NvMediaImageLock	(	NvMediaImage *	image,
		uint32_t	lockAccessType,
		NvMediaImageSurfaceMap *	surfaceMap
	)

Locks an image and returns the associated mapped pointers pointing to the image surface data.

Only images created without the NVM_SURF_ATTR_CPU_ACCESS_UNMAPPED attribute can be accessed by CPU. If an image is being used by an internal engine this function waits until the completion of this operation.

Parameters

[in]	image	Image object
[in]	lockAccessType	Determines the access type. The following access types are supported and may be OR'd together: NVMEDIA_IMAGE_ACCESS_READ Read access NVMEDIA_IMAGE_ACCESS_WRITE Write access NVMEDIA_IMAGE_ACCESS_READ_WRITE Read/Write access
[out]	surfaceMap	Surface descriptors

Returns

NvMediaStatus The completion status of the operation. Possible values are:
NVMEDIA_STATUS_OK
NVMEDIA_STATUS_ERROR

void NvMediaImageUnlock

(

NvMediaImage *

image

)

Unlocks an image.

Internal engines cannot use a surface until it is locked.

Parameters

[in]

image

Image object to unlock

Returns

void