[iadctmatrix] [Up] [iadftmatrix] Image Transformation

iadft
Discrete Fourier Transform.

Synopsis

F = iadft( f )

Implemented in Python.

Input

f	Image. Gray-scale (uint8 or uint16) or binary image (logical).

Output

F	Image. Gray-scale (uint8 or uint16) or binary image (logical).

Examples

>>> f = 255 * iacircle([256,256], 10, [129,129])

>>> iashow(f)

(256, 256) Min= 0 Max= 255 Mean=1.233 Std=17.69

>>> F = iadft(f)

>>> Fv = iadftview(F)

>>> iashow(Fv)

(256, 256) Min= 11 Max= 255 Mean=148.606 Std=27.35


f	Fv

Equation

Source Code
        def iadft(f):
    from Numeric import asarray, Float64, NewAxis, sqrt, matrixmultiply
    f = asarray(f).astype(Float64)
    if len(f.shape) == 1: f = f[:,NewAxis]
    (m, n) = f.shape
    if (n == 1):
        A = iadftmatrix(m)
        F = sqrt(m) * matrixmultiply(A, f)
    else:
        A = iadftmatrix(m)
        B = iadftmatrix(n)
        F = sqrt(m * n) * matrixmultiply(matrixmultiply(A, f), B)
    return F
    
      

iaidft	Inverse Discrete Fourier Transform.
iadftmatrix	Kernel matrix for the DFT Transform.
iadftview	Generate optical Fourier Spectrum for display from DFT data.
iaisdftsym	Check for conjugate symmetry

iadft Discrete Fourier Transform.

Synopsis

Input

Output

Examples

Equation

Source Code

See also

iadft
Discrete Fourier Transform.