PYRMASK(1) 1 (Nov 8, 1987) PYRMASK(1)
NAME
pyrmask - Blend two images together using Gaussian pyramids.
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 produce 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 combine 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
Applications 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
Page 1 (printed 12/1/98)
PYRMASK(1) 1 (Nov 8, 1987) PYRMASK(1)
documented or fully tested.
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