Image Warping

Functions
void	cv::cuda::buildWarpAffineMaps (InputArray M, bool inverse, Size dsize, OutputArray xmap, OutputArray ymap, Stream &stream=Stream::Null())
	Builds transformation maps for affine transformation. More...
void	cv::cuda::buildWarpPerspectiveMaps (InputArray M, bool inverse, Size dsize, OutputArray xmap, OutputArray ymap, Stream &stream=Stream::Null())
	Builds transformation maps for perspective transformation. More...
void	cv::cuda::pyrDown (InputArray src, OutputArray dst, Stream &stream=Stream::Null())
	Smoothes an image and downsamples it. More...
void	cv::cuda::pyrUp (InputArray src, OutputArray dst, Stream &stream=Stream::Null())
	Upsamples an image and then smoothes it. More...
void	cv::cuda::remap (InputArray src, OutputArray dst, InputArray xmap, InputArray ymap, int interpolation, int borderMode=BORDER_CONSTANT, Scalar borderValue=Scalar(), Stream &stream=Stream::Null())
	Applies a generic geometrical transformation to an image. More...
void	cv::cuda::resize (InputArray src, OutputArray dst, Size dsize, double fx=0, double fy=0, int interpolation=INTER_LINEAR, Stream &stream=Stream::Null())
	Resizes an image. More...
void	cv::cuda::rotate (InputArray src, OutputArray dst, Size dsize, double angle, double xShift=0, double yShift=0, int interpolation=INTER_LINEAR, Stream &stream=Stream::Null())
	Rotates an image around the origin (0,0) and then shifts it. More...
void	cv::cuda::warpAffine (InputArray src, OutputArray dst, InputArray M, Size dsize, int flags=INTER_LINEAR, int borderMode=BORDER_CONSTANT, Scalar borderValue=Scalar(), Stream &stream=Stream::Null())
	Applies an affine transformation to an image. More...
void	cv::cuda::warpPerspective (InputArray src, OutputArray dst, InputArray M, Size dsize, int flags=INTER_LINEAR, int borderMode=BORDER_CONSTANT, Scalar borderValue=Scalar(), Stream &stream=Stream::Null())
	Applies a perspective transformation to an image. More...

Detailed Description

Function Documentation

buildWarpAffineMaps()

void cv::cuda::buildWarpAffineMaps	(	InputArray	M,
		bool	inverse,
		Size	dsize,
		OutputArray	xmap,
		OutputArray	ymap,
		Stream &	stream = Stream::Null()
	)

Builds transformation maps for affine transformation.

Parameters

M	2x3 transformation matrix.
inverse	Flag specifying that M is an inverse transformation ( dst=>src ).
dsize	Size of the destination image.
xmap	X values with CV_32FC1 type.
ymap	Y values with CV_32FC1 type.
stream	Stream for the asynchronous version.

See also

cuda::warpAffine , cuda::remap

buildWarpPerspectiveMaps()

void cv::cuda::buildWarpPerspectiveMaps	(	InputArray	M,
		bool	inverse,
		Size	dsize,
		OutputArray	xmap,
		OutputArray	ymap,
		Stream &	stream = Stream::Null()
	)

Builds transformation maps for perspective transformation.

Parameters

M	3x3 transformation matrix.
inverse	Flag specifying that M is an inverse transformation ( dst=>src ).
dsize	Size of the destination image.
xmap	X values with CV_32FC1 type.
ymap	Y values with CV_32FC1 type.
stream	Stream for the asynchronous version.

See also

cuda::warpPerspective , cuda::remap

pyrDown()

void cv::cuda::pyrDown	(	InputArray	src,
		OutputArray	dst,
		Stream &	stream = Stream::Null()
	)

Smoothes an image and downsamples it.

Parameters

src	Source image.
dst	Destination image. Will have Size((src.cols+1)/2, (src.rows+1)/2) size and the same type as src .
stream	Stream for the asynchronous version.

See also

pyrDown

pyrUp()

void cv::cuda::pyrUp	(	InputArray	src,
		OutputArray	dst,
		Stream &	stream = Stream::Null()
	)

Upsamples an image and then smoothes it.

Parameters

src	Source image.
dst	Destination image. Will have Size(src.cols*2, src.rows*2) size and the same type as src .
stream	Stream for the asynchronous version.

remap()

void cv::cuda::remap	(	InputArray	src,
		OutputArray	dst,
		InputArray	xmap,
		InputArray	ymap,
		int	interpolation,
		int	borderMode = BORDER_CONSTANT,
		Scalar	borderValue = Scalar(),
		Stream &	stream = Stream::Null()
	)

Applies a generic geometrical transformation to an image.

Parameters

src	Source image.
dst	Destination image with the size the same as xmap and the type the same as src .
xmap	X values. Only CV_32FC1 type is supported.
ymap	Y values. Only CV_32FC1 type is supported.
interpolation	Interpolation method (see resize ). INTER_NEAREST , INTER_LINEAR and INTER_CUBIC are supported for now.
borderMode	Pixel extrapolation method (see borderInterpolate ). BORDER_REFLECT101 , BORDER_REPLICATE , BORDER_CONSTANT , BORDER_REFLECT and BORDER_WRAP are supported for now.
borderValue	Value used in case of a constant border. By default, it is 0.
stream	Stream for the asynchronous version.

The function transforms the source image using the specified map:

\[\texttt{dst} (x,y) = \texttt{src} (xmap(x,y), ymap(x,y))\]

Values of pixels with non-integer coordinates are computed using the bilinear interpolation.

See also

remap

resize()

void cv::cuda::resize	(	InputArray	src,
		OutputArray	dst,
		Size	dsize,
		double	fx = 0,
		double	fy = 0,
		int	interpolation = INTER_LINEAR,
		Stream &	stream = Stream::Null()
	)

Resizes an image.

Parameters

src	Source image.
dst	Destination image with the same type as src . The size is dsize (when it is non-zero) or the size is computed from src.size() , fx , and fy .
dsize	Destination image size. If it is zero, it is computed as: \[\texttt{dsize = Size(round(fx*src.cols), round(fy*src.rows))}\] Either dsize or both fx and fy must be non-zero.
fx	Scale factor along the horizontal axis. If it is zero, it is computed as: \[\texttt{(double)dsize.width/src.cols}\]
fy	Scale factor along the vertical axis. If it is zero, it is computed as: \[\texttt{(double)dsize.height/src.rows}\]
interpolation	Interpolation method. INTER_NEAREST , INTER_LINEAR and INTER_CUBIC are supported for now.
stream	Stream for the asynchronous version.

See also

resize

rotate()

void cv::cuda::rotate	(	InputArray	src,
		OutputArray	dst,
		Size	dsize,
		double	angle,
		double	xShift = 0,
		double	yShift = 0,
		int	interpolation = INTER_LINEAR,
		Stream &	stream = Stream::Null()
	)

Rotates an image around the origin (0,0) and then shifts it.

Parameters

src	Source image. Supports 1, 3 or 4 channels images with CV_8U , CV_16U or CV_32F depth.
dst	Destination image with the same type as src . The size is dsize .
dsize	Size of the destination image.
angle	Angle of rotation in degrees.
xShift	Shift along the horizontal axis.
yShift	Shift along the vertical axis.
interpolation	Interpolation method. Only INTER_NEAREST , INTER_LINEAR , and INTER_CUBIC are supported.
stream	Stream for the asynchronous version.

See also

cuda::warpAffine

warpAffine()

void cv::cuda::warpAffine	(	InputArray	src,
		OutputArray	dst,
		InputArray	M,
		Size	dsize,
		int	flags = INTER_LINEAR,
		int	borderMode = BORDER_CONSTANT,
		Scalar	borderValue = Scalar(),
		Stream &	stream = Stream::Null()
	)

Applies an affine transformation to an image.

Parameters

src	Source image. CV_8U , CV_16U , CV_32S , or CV_32F depth and 1, 3, or 4 channels are supported.
dst	Destination image with the same type as src . The size is dsize .
M	2x3 transformation matrix.
dsize	Size of the destination image.
flags	Combination of interpolation methods (see resize) and the optional flag WARP_INVERSE_MAP specifying that M is an inverse transformation ( dst=>src ). Only INTER_NEAREST , INTER_LINEAR , and INTER_CUBIC interpolation methods are supported.
borderMode
borderValue
stream	Stream for the asynchronous version.

See also

warpAffine

warpPerspective()

void cv::cuda::warpPerspective	(	InputArray	src,
		OutputArray	dst,
		InputArray	M,
		Size	dsize,
		int	flags = INTER_LINEAR,
		int	borderMode = BORDER_CONSTANT,
		Scalar	borderValue = Scalar(),
		Stream &	stream = Stream::Null()
	)

Applies a perspective transformation to an image.

Parameters

src	Source image. CV_8U , CV_16U , CV_32S , or CV_32F depth and 1, 3, or 4 channels are supported.
dst	Destination image with the same type as src . The size is dsize .
M	3x3 transformation matrix.
dsize	Size of the destination image.
flags	Combination of interpolation methods (see resize ) and the optional flag WARP_INVERSE_MAP specifying that M is the inverse transformation ( dst => src ). Only INTER_NEAREST , INTER_LINEAR , and INTER_CUBIC interpolation methods are supported.
borderMode
borderValue
stream	Stream for the asynchronous version.

See also

warpPerspective