Manual: ppmshift

Ppmshift User Manual(1)				   General Commands Manual			     Ppmshift User Manual(1)

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 pixels.	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.  Unfortunately, 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.

OPTIONS
       There are no command line options defined specifically for ppmshift, but it recognizes the options common to all pro‐
       grams based on libnetpbm (See  Common Options .)

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
	    pamcat -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(1), pamcut(1), pamflip(1), ppmdim(1), pamcat(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(1)