cddm.window

Windowing functions.

These windowing functions can be used to generate FFT window functions.

Module Contents

cddm.window.blackman(shape, out=None)

Returns a blacman window of a given shape.

Parameters

• shape ((int,int)) – A shape of the 2D window.

• out (ndarray, optional) – Output array.

Returns

window – A Blackman window

Return type

ndarray

cddm.window.gaussian(shape, sigma, out=None)

Gaussian window function.

Parameters

• shape ((int,int)) – A shape of the 2D window

• sigma (float) – Waist of the gaussian in units of total width of the frame.

• out (ndarray, optional) – Output array.

Returns

window – Gaussian beam window

Return type

ndarray

cddm.window.tukey(shape, alpha, out=None)

Returns a tukey window function.

Parameters

• shape ((int,int)) – A shape of the 2D window

• alpha (float) – Smoothnes parameter - defines smoothness of the edge of the tukey (should be between 0. and 1. When set to zero, it becomes an aperture filter. When set to 1 it becomes a Hann window.

• out (ndarray, optional) – Output array.

Returns

window – Tukey window

Return type

ndarray

cddm.window.hann(shape, out=None)

Returns a hann window function.

Parameters

• shape ((int,int)) – A shape of the 2D window

• out (ndarray, optional) – Output array.

Returns

window – Hann window

Return type

ndarray

cddm.window.plot_windows(shape=(256, 256), alpha=0.5, sigma=0.4)

Plots all windows with a given shape, alpha (for tukey), sigma (for gaussian) values