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)