PYRMASK(1)                                           PYRMASK(1)





NAME
       pyrmask - Blend two images together using Gaussian pyra-
       mids.

SYNOPSIS
       pyrmask [ -l levels ] [  -o  outfile  ]  inmask  outmask
       maskfile

DESCRIPTION
       Pyrmask blends two images together by first breaking the
       images down into  separate  bandpass  images,  combining
       these  separate images, and then adding the new bandpass
       images back into a single output image.  This  can  pro-
       duce  very  seamless  blends of digital images.  The two
       images are combined on  the  basis  of  a  third  "mask"
       image.   The  resulting  image  will  contain the inmask
       image where the mask contains a maximum value (255)  and
       the  outmask  image where the mask contains zeros.  This
       is done on a channel by channel basis, i.e. the maskfile
       should  have data in each channel describing how to com-
       bine each channel of the inmask and outmask images.  All
       three images must have exactly the same dimensions (both
       image size and number of channels).  For  best  results,
       it's often useful to filter the mask image a little with
       smush(1) first.

OPTIONS
       -l levels
              How many pyramid levels to use (maximum is log(2)
              of image size).

       -o outfile
              If  specified,  output  will  be  written to this
              file, otherwise it will go to stdout.

SEE ALSO
       smush(1), rleswap(1), urt(1), RLE(5),
       Burt and Adelson, "A Multiresolution Spline With  Appli-
       cations to Image Mosaics", ACM Transactions on Graphics,
       October 1983, V2 #4, p. 217.
       Ogden, Adelson, Bergen and Burt, "Pyramid-based Computer
       Graphics", RCA Engineer, Sept/Oct 1985, p. 4.

AUTHOR
       Rod Bogart

BUGS
       The  current implementation has very strict requirements
       for image sizes and dimensions.  The  extensive  use  of
       floating point computation makes it very slow for normal
       sized images.  It also keeps all of the bandpass  images
       in  core at once, which requires considerable amounts of
       memory.

       Pyrmask is built on top of a library  of  functions  for
       working with Gaussian pyramids.  This library has yet to
       be documented or fully tested.



1                         Nov 8, 1987                PYRMASK(1)
