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`despike(`

`x` [, frac=`frac`, level=`level`,
niter=`niter`, spikes=`spikes`, rms=`rms`])

This function returns a copy of two-dimensional image

from which (radiation) spikes have been removed.
`x`

`frac`If the average of the eight nearest neighbor pixels is less than

`1 -`

times the central pixel value, then the pixel is declared to be bad. Defaults to 0.25.`frac`)`level`An index into a sorted list of data values from neighboring pixels, to replace bad pixels. Only values between 0 and 15 are useful. Defaults to 7.

`niter`The number of despike iterations to apply. Defaults to 1 and must not exceed 20.

`spikes`If non-zero, then 8x8 cells are zapped if they contain

or more spikes. This option is intended for use with images that were restored by jpeg decompression, and requires that the dimensions of`spikes`

be multiples of 8.`x``rms`If non-zero, then 8x8 cells are zapped if they show an rms data value variation exceeding

. This option is intended for use with images that were restored by jpeg decompression, and requires that the dimensions of`rms`

be multiples of 8.`x`