Perspective Warp

Applies a perspective warp on an image. More...

Typedefs
typedef float	VPIPerspectiveTransform[3][3]
	Represents a 2D perspective transform. More...

Functions
VPIStatus	vpiSubmitPerspectiveWarp (VPIStream stream, uint64_t backend, VPIImage input, const VPIPerspectiveTransform xform, VPIImage output, const VPIWarpGrid *grid, VPIInterpolationType interp, VPIBorderExtension border, uint64_t flags)
	Submits a Perspective Warp operation to the stream. More...

Detailed Description

Applies a perspective warp on an image.

Refer to Perspective Warp for more details and usage examples.

Typedef Documentation

VPIPerspectiveTransform

typedef float VPIPerspectiveTransform[3][3]

#include </opt/nvidia/vpi3/include/vpi/Types.h>

Represents a 2D perspective transform.

[vx]   [a11 a12 tx] [ux]
[vy] = [a21 a22 ty] [uy]
[vw]   [ p0  p1  p] [ 1]
u'x  = vx/vw
u'y  = vy/vw

In these equations,

• ux, uy are the inhomogeneous coordinates in the source image.
• u'x, u'y are the inhomogeneous coordinates in the destination image.
• vx,vy,vw are the homogeneous coordinates in the destination image.
• a11,a12,a21,a22 are the2x2 non-singular matrix with the linear component of the transform.
• tx,ty is the translation component of the transform.
• p0,p1,p are the projective components of the transform. p is usually 1.

Definition at line 667 of file Types.h.

Function Documentation

vpiSubmitPerspectiveWarp()

VPIStatus vpiSubmitPerspectiveWarp	(	VPIStream	stream,
		uint64_t	backend,
		VPIImage	input,
		const VPIPerspectiveTransform	xform,
		VPIImage	output,
		const VPIWarpGrid *	grid,
		VPIInterpolationType	interp,
		VPIBorderExtension	border,
		uint64_t	flags
	)

#include </opt/nvidia/vpi3/include/vpi/algo/PerspectiveWarp.h>

Submits a Perspective Warp operation to the stream.

Parameters

[in]	stream	The stream where the operation will be queued in. Must not be NULL. Stream must have enabled the backends that will execute the algorithm.
[in]	backend	VPI backends that are eligible to execute the algorithm. Valid values: VPI_BACKEND_CPU VPI_BACKEND_CUDA VPI_BACKEND_VIC
[in]	input	Input image to be warped. Must not be NULL. Image must have enabled the backends that will execute the algorithm. On VIC, minimum input dimensions is 64x16 and even. The accepted image formats are: Formats CPU CUDA VIC VPI_IMAGE_FORMAT_U8 * * * VPI_IMAGE_FORMAT_U8_BL * * * VPI_IMAGE_FORMAT_S8 * * VPI_IMAGE_FORMAT_U16 * * VPI_IMAGE_FORMAT_S16 * * VPI_IMAGE_FORMAT_F32 * * VPI_IMAGE_FORMAT_Y8_ER * * * VPI_IMAGE_FORMAT_Y8_ER_BL * VPI_IMAGE_FORMAT_Y16_ER * * VPI_IMAGE_FORMAT_RGB8 * * VPI_IMAGE_FORMAT_BGR8 * * VPI_IMAGE_FORMAT_RGBA8 * * VPI_IMAGE_FORMAT_BGRA8 * * VPI_IMAGE_FORMAT_NV12 * VPI_IMAGE_FORMAT_NV12_ER * * * VPI_IMAGE_FORMAT_NV12_BL * VPI_IMAGE_FORMAT_NV12_ER_BL * VPI_IMAGE_FORMAT_NV24 * VPI_IMAGE_FORMAT_NV24_ER *
[in]	xform	Transform to be applied.
[out]	output	Output image where warped image is written to. Dimensions may be different from input. Must not be NULL. Image must have enabled the backends that will execute the algorithm. Must have same format as input image. Dimensions must be even.
[in]	grid	Grid on the output to establish performance/quality trade-offs. A dense grid will result in best quality, albeit slower performance. Grid must be set depending on the perf/quality criteria needed. Pass NULL as a shortcut for using a dense grid. CPU and CUDA only accept dense grids. Grid dimensions must match output dimensions.
[in]	interp	Interpolation mode to be used when source coordinate doesn't fall exactly on pixel center. Valid values: VPI_INTERP_NEAREST VPI_INTERP_LINEAR VPI_INTERP_CATMULL_ROM
[in]	border	Border extension to use for samples that fall outsize input's bounds. The accepted border extensions are: VPI_BORDER_ZERO
[in]	flags	Flags to modify algorithm behavior. Can be a combination of one or more of the following values: 0 : default, transform maps the input into the output VPI_WARP_INVERSE : transform maps the output back into the input. VPI_PRECISE : precise, but potentially slower implementation.

Return values

VPI_ERROR_INVALID_ARGUMENT	stream is NULL.
VPI_ERROR_INVALID_ARGUMENT	input or output are NULL.
VPI_ERROR_INVALID_ARGUMENT	xform is NULL.
VPI_ERROR_INVALID_ARGUMENT	Invalid flags.
VPI_ERROR_INVALID_ARGUMENT	input and output must have the same format.
VPI_ERROR_INVALID_ARGUMENT	border not supported.
VPI_ERROR_INVALID_ARGUMENT	backend is invalid or unknown.
VPI_ERROR_INVALID_ARGUMENT	input and/or output dimensions not supported.
VPI_ERROR_INVALID_ARGUMENT	grid configuration not supported by backend.
VPI_ERROR_INVALID_ARGUMENT	grid dimensions don't match output image's.
VPI_ERROR_INVALID_IMAGE_FORMAT	Image format not supported.
VPI_ERROR_NOT_IMPLEMENTED	Perspective Warp algorithm is not supported by given backend.
VPI_ERROR_INVALID_OPERATION	Backend hardware not available.
VPI_ERROR_INVALID_OPERATION	The needed backends aren't enabled in stream, input or output.
VPI_SUCCESS	Operation executed successfully.