## LsfToPsf

##### >Psychtoolbox>PsychOptics

LSFToPSF Convert a line spread function to a point spread function.

psf = LSFTOPSF(lsf,varargin)

This works by taking the lsf into the one-dimensional frequency domain

(i.e. get the 1D MTF) and then creating a circularly symmetric version

of this. The 2D frequency representation is then converted back to the

spatial domain to produce the psf. This produces a spatially-symmetric

PSF consistent with the measured line spread function.

This method is described by Marchand, 1964, JOSA, 54, 7, pp. 915-919

and is one of several methods provided. In 1964, taking the Fourier

transform was computationally intense.

There is a second paper by Marchand (1965, JOSA, 55, 4, 352-354) which

treats the more general case where you have line spread functions for

many orientations and want to recover an psf that is not necessarily

spatially-symmetric.

The lsf must be spatially symmetric. This makes sense given that we

are going to recover a spatially symmetric psf.

You want to make sure that the spatial suport is large enough to

capture the full lsf.

The returned psf is normalized to have unit volume.

See also PSFTOLSF, PSYCHOPTICSTEST

`Psychtoolbox/PsychOptics/LsfToPsf.m`