CV.Transforms

Various image transformations from opencv and other sources.

Documentation

takeEvenSized :: Image c d -> Image c d

Since DCT is valid only for even sized images, we provide a function to crop images to even sizes.

dct :: Image GrayScale d -> Image GrayScale d

Perform Discrete Cosine Transform

idct :: Image GrayScale d -> Image GrayScale d

Perform Inverse Discrete Cosine Transform

data MirrorAxis

Constructors

Vertical

Horizontal

Instances

Eq MirrorAxis

Show MirrorAxis

flip :: CreateImage (Image c d) => MirrorAxis -> Image c d -> Image c d

Mirror an image over a cardinal axis

rotate :: Double -> Image c d -> Image c d

Rotate img angle radians.

data Interpolation

Constructors

NearestNeighbour

Linear

Area

Cubic

Instances

Enum Interpolation

Eq Interpolation

Ord Interpolation

Show Interpolation

radialDistort :: Image GrayScale D32 -> Double -> Image GrayScale D32

Simulate a radial distortion over an image

scaleSingleRatio :: (RealFloat a, CreateImage (Image c D32)) => Interpolation -> a -> Image c D32 -> Image c D32

Scale image by one ratio on both of the axes

scale :: (CreateImage (Image c D32), RealFloat a) => Interpolation -> (a, a) -> Image c D32 -> Image c D32

Scale an image with different ratios for axes

scaleToSize :: CreateImage (Image c D32) => Interpolation -> Bool -> (Int, Int) -> Image c D32 -> Image c D32

Scale an image to a given size

perspectiveTransform :: Real a => Image c d -> [a] -> Image c d

Apply a perspective transform to the image. The transformation 3x3 matrix is supplied as a row ordered, flat, list.

perspectiveTransform' :: CreateImage (Image c d) => Matrix Float -> Image c d -> (Int, Int) -> Image c d

getHomography :: Real a => [(a, a)] -> [(a, a)] -> [CDouble]

Find a homography between two sets of points in. The resulting 3x3 matrix is returned as a list.

data HomographyMethod

Constructors

Default

Ransac

LMeds

Instances

Enum HomographyMethod

getHomography' :: Matrix Float -> Matrix Float -> HomographyMethod -> Float -> Matrix Float

evenize :: Image channels depth -> Image channels depth

Return a copy of an image with an even size

oddize :: Image channels depth -> Image channels depth

Return a copy of an image with an odd size

sameSizePad :: Image channels depth -> Image c d -> Image channels depth

Pad images to same size

cv_Gaussian :: CInt

pyrDown :: CreateImage (Image GrayScale a) => Image GrayScale a -> Image GrayScale a

Downsize image by 50% efficiently. Image dimensions must be even.

pyrUp :: CreateImage (Image GrayScale a) => Image GrayScale a -> Image GrayScale a

safePyrDown :: CreateImage (Image GrayScale depth) => Image GrayScale depth -> Image GrayScale depth

minEnlarge :: Image GrayScale D32 -> Image GrayScale D32

Enlargen the image so that its size is a power of two.

gaussianPyramid :: Image GrayScale D32 -> [Image GrayScale D32]

Calculate an infinite gaussian pyramid of an image while keeping track of various corner cases and gotchas.

laplacianPyramid :: Int -> Image GrayScale D32 -> [Image GrayScale D32]

Calculate the laplacian pyramid of an image up to the nth level. Notice that the image size must be divisible by 2^n or opencv will abort (TODO!)

reconstructFromLaplacian :: [Image GrayScale D32] -> Image GrayScale D32

Reconstruct an image from a laplacian pyramid

enlarge :: Int -> Image GrayScale D32 -> Image GrayScale D32

Enlargen the image so that its size is divisible by 2^n. Fill the area outside the image with black.

enlargeShadow :: Int -> Image GrayScale D32 -> Image GrayScale D32

 Enlargen the image so that its size is is divisible by 2^n. Replicate the border of the image.

data DistanceType

Constructors

C

L1

L2

Instances

Enum DistanceType

data MaskSize

Mask sizes accepted by distanceTransform

Constructors

M3

M5

Instances

Enum MaskSize

Eq MaskSize

Ord MaskSize

Show MaskSize

distanceTransform :: DistanceType -> MaskSize -> Image GrayScale D8 -> Image GrayScale D32

cvDCT :: Ptr () -> Ptr () -> CInt -> IO ()

cvFlip :: Ptr () -> Ptr () -> CInt -> IO ()

rotateImage :: Ptr BareImage -> CDouble -> CDouble -> IO (Ptr BareImage)

radialRemap :: Ptr BareImage -> Ptr BareImage -> CDouble -> IO ()

cvResize :: Ptr () -> Ptr () -> CInt -> IO ()

wrapPerspective :: Ptr BareImage -> CDouble -> CDouble -> CDouble -> CDouble -> CDouble -> CDouble -> CDouble -> CDouble -> CDouble -> IO (Ptr BareImage)

wrapWarpPerspective :: Ptr () -> Ptr () -> Ptr () -> IO ()

findHomography :: Ptr CDouble -> Ptr CDouble -> CInt -> Ptr CDouble -> IO ()

cvFindHomography :: Ptr () -> Ptr () -> Ptr () -> CInt -> CDouble -> Ptr () -> IO CInt

makeEvenUp :: Ptr BareImage -> IO (Ptr BareImage)

padUp :: Ptr BareImage -> CInt -> CInt -> IO (Ptr BareImage)

cvPyrDown :: Ptr () -> Ptr () -> CInt -> IO ()

cvPyrUp :: Ptr () -> Ptr () -> CInt -> IO ()

blitShadow :: Ptr BareImage -> Ptr BareImage -> IO ()

cvDistTransform :: Ptr () -> Ptr () -> CInt -> CInt -> Ptr CFloat -> Ptr () -> IO ()