RadonTransform

Radon Transform

Purpose

This utility allows you to compute the Radon or Fourier-Radon transform of images and volumes. These are needed for a posterior angular_refinement. These operations are performed via Spider through the operationrm3dn.

Several files are generated through spider call:superfeo.fft,superfeo2.fft andb01.fft, although they are removed after the call

In order to run this program you must set an environment variable called SPIDER to the name of your spider command in your system, like this

# For TCSH
$ setenv SPIDER spider4

# For BASH
$ export SPIDER=spider4

Usage

$ radon_transform ...

Parameters

• __OR__ Radon transform a single file

• __OR__ If no output file is given, then the input one is rewritten

• `` Radon transform a bunch of files

• __OR__ If no output extension neither root are given, then the input ones are rewritten

• -delta_rot [Delta2] = Spacing for the Radon transform in the rotational angle

• -delta_tilt [Delta2] = Spacing for the Radon transform in the tilting angle. Only valid for volumes

• -output_size [size-1] = Size of the output Radon transform. By default, 1.5 times the input size

• -low_pass [w0] = Low pass filtering of the volume/image before transforming. This frequency is normalized to 0.5. See xmipp_fourier_filter

• -temperature [t0.02] = Parameter for a Fermi low pass filtering

• `` Usually only the Fourier transform of the Radon transform is needed. Use this option to compute the Fourier transform of the Radon transform of a volume or image in a single step. There is only one output file

Examples and notes

Compute the Fourier-Radon transform of a volume

$ xmipp_radon_transform -i volume.vol -o volume.frt -fourier -low_pass 0.26

Compute the Fourier-Radon transform of a set of images

$ xmipp_radon_transform -i selfile.sel -oext frt -fourier -low_pass 0.26 

--Main.AlfredoSolano - 18 Jan 2007