Radiance ra_gif program

RA_GIF(1)                                                            RA_GIF(1)

NAME

       ra_gif - convert RADIANCE picture to Compuserve GIF

SYNOPSIS

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

DESCRIPTION

       Ra_gif converts from RADIANCE  to  Compuserve  GIF  color-mapped,  com-
       pressed  image  files.  In the default mode, a RADIANCE picture is con-
       verted 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 speci-
       fies a sampling factor for neural  network  color  quantization.   This
       value  should  be  between 1 and 80, where 1 takes the longest and pro-
       duces 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)