RLEBG(1)                                               RLEBG(1)





NAME
       rlebg - generate simple backgrounds

SYNOPSIS
       rlebg  [ -l ] [ -v [ top [ bottom ] ] ] [ -s xsize ysize
       ] [ -o outfile ] red green blue [ alpha ]

DESCRIPTION
       rlebg generates a simple background.   These  are  typi-
       cally used for compositing below other images.  The val-
       ues red green blue specify the pixel values  (between  0
       and  255)  the  background  will  have.  If alpha is not
       specified, it defaults to 255  (full  coverage).   rlebg
       generates both constant backgrounds and backgrounds with
       continuous ramps.

OPTIONS
       -s xsize ysize
              This is the size of the  background  image.   The
              default is 512x480.

       -l     Generate  a  linear  ramp of pixel values.  If no
              ramp flag is given, rlebg  generates  a  constant
              background.

       -v top bottom
              Generate a variable ramp, using a quadratic func-
              tion  (this  looks  best  with  gamma   corrected
              images).  top and bottom are the fractions of the
              full color values at the top and  bottom  of  the
              image.   The  defaults are 1.0 0.1, respectively.
              If both -v and -l are given, then a  linear  ramp
              function is used instead of a quadratic ramp.

       -o outfile
              If  specified, the output will be written to this
              file.  If outfile is "-", or if it is not  speci-
              fied,  the output will be written to the standard
              output stream.


SEE ALSO
       rlesetbg(1), urt(1), RLE(5).

AUTHOR
       Rod Bogart



1                      November 12, 1986               RLEBG(1)
