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Ppmshift User Manual(0)				       Ppmshift	User Manual(0)

NAME
       ppmshift	- shift	lines of a PPM image left or right by a	random amount

SYNOPSIS
       ppmshift	shift [ppmfile]

DESCRIPTION
       This program is part of Netpbm(1).

       ppmshift	reads a	PPM image as input.  It	shifts every row of image data
       to the left or right by a random	amount,	within a range of  shift  pix-
       els.  The random	distribution is	uniform, centered at zero movement.

       The  randomness	in  the	image is limited before	Netpbm 10.37 (December
       2006) --	if you run the program twice in	the same second, you  may  get
       identical output.

       This  is	an effect the author intended to use for MPEG tests.  Unfortu-
       nately, this program is not useful for that -  it  creates  too	random
       patterns	 to  be	used for animations.  Still, it	might give interesting
       results on still	images.

EXAMPLE
       Check this out: Save your favorite model's picture from something  like
       alt.binaries.pictures.supermodels   (ok,	 or  from  any	other  picture
       source),	convert	it to ppm, and process it e.g. like this, assuming the
       picture is 800x600 pixels:

	    #take the upper half, and leave it like it is
	    pamcut -top=0 -width=800 -height=300 cs.ppm	>upper.ppm

	    #take the lower half, flip it upside down, dim it and distort it a little
	    pamcut -top=300 -width=800 -height=300 cs.ppm | \
		pamflip	-topbottom | \
		ppmdim 0.7 | \
		ppmshift 10 >lower.ppm

	    #and concatenate the two pieces
	    pnmcat -topbottom upper.ppm	lower.ppm >newpic.ppm

       The  resulting  picture looks like the image being reflected on a water
       surface with slight ripples.

SEE ALSO
       ppm(5), pamcut(1), pamflip(1), ppmdim(1), pnmcat(1)

AUTHOR
       Copyright (C) 1993 by Frank Neumann

DOCUMENT SOURCE
       This manual page	was generated by the Netpbm tool 'makeman'  from  HTML
       source.	The master documentation is at

	      http://netpbm.sourceforge.net/doc/ppmshift.html

netpbm documentation	       20 November 2008	       Ppmshift	User Manual(0)

NAME | SYNOPSIS | DESCRIPTION | EXAMPLE | SEE ALSO | AUTHOR | DOCUMENT SOURCE

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