Graphics.Image.Processing.Complex

Rectangular form

(!+!) :: (Applicative (Pixel cs), Array arr cs e, Array arr cs (Complex e)) => Image arr cs e -> Image arr cs e -> Image arr cs (Complex e) infix 6

Construct a complex image from two images representing real and imaginary parts.

>>> frog <- readImageRGB VU "images/frog.jpg"
>>> frog !+! 0
<Image VectorUnboxed RGB (Complex Double): 200x320>
>>> frog !+! frog
<Image VectorUnboxed RGB (Complex Double): 200x320>

realPartI :: (Applicative (Pixel cs), Array arr cs e, Array arr cs (Complex e), RealFloat e) => Image arr cs (Complex e) -> Image arr cs e

Extracts the real part of a complex image.

imagPartI :: (Applicative (Pixel cs), Array arr cs e, Array arr cs (Complex e), RealFloat e) => Image arr cs (Complex e) -> Image arr cs e

Extracts the imaginary part of a complex image.

Polar form

mkPolarI :: (Applicative (Pixel cs), Array arr cs e, Array arr cs (Complex e), RealFloat e) => Image arr cs e -> Image arr cs e -> Image arr cs (Complex e)

Form a complex image from polar components of magnitude and phase.

cisI :: (Applicative (Pixel cs), Array arr cs e, Array arr cs (Complex e), RealFloat e) => Image arr cs e -> Image arr cs (Complex e)

cisI t is a complex image with magnitude 1 and phase t (modulo 2*pi).

polarI :: (Applicative (Pixel cs), Array arr cs e, Array arr cs (Complex e), RealFloat e) => Image arr cs (Complex e) -> (Image arr cs e, Image arr cs e)

The function polar' takes a complex image and returns a (magnitude, phase) pair of images in canonical form: the magnitude is nonnegative, and the phase in the range (-pi, pi]; if the magnitude is zero, then so is the phase.

magnitudeI :: (Applicative (Pixel cs), Array arr cs e, Array arr cs (Complex e), RealFloat e) => Image arr cs (Complex e) -> Image arr cs e

The nonnegative magnitude of a complex image.

phaseI :: (Applicative (Pixel cs), Array arr cs e, Array arr cs (Complex e), RealFloat e) => Image arr cs (Complex e) -> Image arr cs e

The phase of a complex image, in the range (-pi, pi]. If the magnitude is zero, then so is the phase.

Conjugate

conjugateI :: (Applicative (Pixel cs), Array arr cs (Complex e), RealFloat e) => Image arr cs (Complex e) -> Image arr cs (Complex e)

The conjugate of a complex image.

Processing

makeFilter

Arguments

:: (Array arr cs e, RealFloat e)

=> (Int, Int)

Dimensions of the filter. Both m and n have to be powers of 2, i.e. m == 2^k, where k is some integer.

-> ((Int, Int) -> Pixel cs e)

-> Image arr cs e

Make a filter by using a function that works around a regular (x, y) coordinate system.

applyFilter

Arguments

:: (Applicative (Pixel cs), Array arr cs e, Array arr cs (Complex e), Fractional (Pixel cs (Complex e)), Floating (Pixel cs e), RealFloat e)

=> Image arr cs e

Source image.

-> Image arr cs e

Filter.

-> Image arr cs e

Apply a filter to an image created by makeFilter.

Fourier Transform

fft :: (Applicative (Pixel cs), Array arr cs (Complex e), ColorSpace cs e, Fractional (Pixel cs (Complex e)), Floating (Pixel cs e), RealFloat e) => Image arr cs (Complex e) -> Image arr cs (Complex e)

Fast Fourier Transform

ifft :: (Applicative (Pixel cs), Array arr cs (Complex e), ColorSpace cs e, Fractional (Pixel cs (Complex e)), Floating (Pixel cs e), RealFloat e) => Image arr cs (Complex e) -> Image arr cs (Complex e)

Inverse Fast Fourier Transform