NAME

       ra_gif - convert RADIANCE picture to Compuserve GIF

SYNOPSIS

       ra_gif [ -b ][ -d ][ -c ncolors ][ -g gamma ][ -e +/-stops ][ -n sampfac ] input [ output ]

DESCRIPTION

       Ra_gif  converts  from  RADIANCE  to Compuserve GIF color-mapped, compressed image files.  In the default
       mode, a RADIANCE picture is converted to a color-mapped GIF file of  the  same  horizontal  and  vertical
       dimensions  with  8-bits  per pixel.  The -b option converts the image to black and white.  The -d option
       turns off dithering.  The -c option allows fewer than 256 colors (and fewer than 8 bits per pixel).   The
       -g  option specifies the exponent used in gamma correction; the default value is 2.2.  An exponent of 1.0
       turns gamma correction off.  The -e option specifies an exposure compensation in f-stops (powers of two).
       Only integer stops are allowed, for efficiency.  The -n option specifies a  sampling  factor  for  neural
       network  color  quantization.   This  value  should  be  between  1 and 80, where 1 takes the longest and
       produces the best results in small areas of the image.  If  no  value  is  given,  a  faster  median  cut
       algorithm is used.  If the output file is missing, the standard output is used.

AUTHORS

       Greg Ward
       Paul Haeberli
       David Rowley
       Anthony Dekker provided the code for neural network color quantization

SEE ALSO

       pfilt(1),   ra_bmp(1),  ra_bn(1),  ra_ppm(1),  ra_pr(1),  ra_pr24(1),  ra_t8(1),  ra_t16(1),  ra_tiff(1),
       ximage(1)

RADIANCE                                             6/10/94                                           RA_GIF(1)