NAME

       compamb - compute good ambient value for a rad input file

SYNOPSIS

       compamb [ -c ][ -e ] rad_input_file

DESCRIPTION

       Compamb  computes  a good ambient value for the specified rad(1) variable file and appends it to the file
       as a "render= -av" option.  If the -c option is specified, then compamb includes color information in the
       computed ambient value, rather than estimating a grey value to avoid rendering color shifts.  If  the  -e
       option  is  specified, then compamb also computes a good exposure value for this scene, and appends it to
       the rad file as well.

       Compamb is a shell script that makes calls to other RADIANCE programs and  utilities  to  do  the  actual
       work.  A substantial amount of time may be required to complete this script, since compamb calls rpict(1)
       to  render  low  resolution  frames  for  each  view  in  the rad file, setting "QUALITY=High" to compute
       interreflections.  The resulting ambient file is thrown away, since it would disagree with  the  new  -av
       setting  used  for  the  final renderings.  This method is preferable to setting the -aw option of rpict,
       which frequently results in splotchy artifacts.

AUTHOR

       Greg Ward Larson

SEE ALSO

       lookamb(1), rad(1), rpict(1)

RADIANCE                                             1/23/98                                          COMPAMB(1)