# magni.imaging.dictionaries._visualisations module¶

Module providing functionality for visualising dictionary coefficients.

## Routine listings¶

visualise_DCT(shape)
Function for visualising DCT coefficients.
visualise_DFT(shape)
Function for visualising DFT coefficients.
magni.imaging.dictionaries._visualisations.visualise_DCT(shape)[source]

Return utilities for visualising DCT coefficients.

A handle to a function to transform the coefficients into a ‘displayable’ format is returned along with a tuple of ranges of the axes in the 2D coefficient plane.

Parameters: shape (tuple) – The shape of the 2D DCT being visualised. display_coefficients (Function) – The function used to transform coefficients into a ‘displayable’ format. axes_extent (tuple) – The ranges of the axes in the 2D coefficient plane.

Notes

The display_coefficients function takes log10 to the absolute value of the transform cofficient vector given to it as an argument. The returned displayable coefficients is a matrix.

The axes_extent consists of (abcissa_min, abcissa_max, ordinate_min, ordinate_max).

magni.imaging.dictionaries._visualisations.visualise_DFT(shape)[source]

Return utilities for visualising DFT coefficients.

A handle to a function to transform the coefficients into a ‘displayable’ format is returned along with a tuple of ranges of the axes in the 2D coefficient plane.

Parameters: shape (tuple) – The shape of the 2D DFT being visualised. display_coefficients (Function) – The function used to transform coefficients into a ‘displayable’ format. axes_extent (tuple) – The ranges of the axes in the 2D coefficient plane.

Notes

The display_coefficients function takes log10 to the absolute value of the transform cofficient vector given to it as an argument. The returned displayable coefficients is a matrix that is flipped up/down and fftshifted.

The axes_extent consists of (abcissa_min, abcissa_max, ordinate_min, ordinate_max).