Boulder Laboratory for 3-Dimensional Electron Microscopy of Cells

TAPERVOLEDGE(1)							TAPERVOLEDGE(1)

NAME
	tapervoledge - to excise a subset of a volume, taper the edges, and pad

SYNOPSIS
	tapervoledge

DESCRIPTION
  This program will cut a subset out of an image volume, taper the
  intensity down to the mean value at the edge of the volume over
  a specified range of pixels, and embed this subset into a larger
  volume with specified borders.  The resulting volume will have
  dimensions suitable for taking the FFT.  As a special case, a single
  X/Y plane may be excised and tapered at its edges.
  
  Inputs to the program:
  
  Name of input file
  
  Name of output file
  
  Dimensions of the block to cut out, in X, Y and Z.  The default is
  the whole volume.
  
  The index coordinates (ix, iy, iz) of the center of the block.  The
  default is the center of the input volume.
  
  The width of the borders, in X, Y, and Z, with which to pad the
  image block.  Borders will be made larger as necessary to make the
  output image size suitable for taking an FFT.  If the dimension being
  excised in Z is 1, then padding must be zero in Z.
  
  The extent in X, Y, and Z over which to taper the image intensity
  down to the mean at the edge.  For example, if an extent of 3 is
  used for the X direction, the last three pixels on a line would be
  attenuated toward the mean value by 1/4, 1/2, and 3/4.
  
  The program will stop with an error message if the subset or the
  output image is too large, or if the subset is not entirely within
  the input volume.

HISTORY
	  Written by David Mastronarde  7/22/97; 2/2/01: taper a single slice.