Radiance ra_ps program

RA_PS(1)                                                              RA_PS(1)

NAME

       ra_ps - convert RADIANCE picture to a PostScript file

SYNOPSIS

       ra_ps  [  -b|c ][ -A|B|C ][ -n ncopies ][ -e +/-stops ][ -g gamma ][ -p
       paper ][ -m[h|v] margin ][ -d dpi ] [ input [ output ] ]

DESCRIPTION

       Ra_ps translates a RADIANCE picture to a color or greyscale Adobe Post-
       Script file for printing on a laser printer or importing to a page lay-
       out program.  The -b option tells ra_ps to  produce  greyscale  output.
       (The  default  is  color, which may be specified explicitly with the -c
       option.)

       The -A option specifies that the output should be in uncompressed ASCII
       hexstring  format (the default).  The -B option specifies that the out-
       put should be in uncompressed binary string format.  The file size will
       be  roughly  half  that  of the ASCII equivalent, but some printers and
       especially some printer connections do not support binary transfer,  so
       this  option should be used with caution.  The -C option specifies that
       the output should be in run-length compressed ASCII format.   The  file
       size will be one half to one tenth as large as the hexstring equivalent
       and can be sent over any network or by e-mail.  The  only  disadvantage
       is  that  it will actually take longer to print on some printers, since
       the  "readhexstring"  procedure  is  generally  faster  than  a  custom
       replacement.

       The  -n  option  specifies the number of copies to print of this image.
       It is often preferable to use this option instead of the multiple  copy
       option  of the print spooler program, since the latter often results in
       duplication of the input file with a large associated cost.

       The -e option specifies an exposure compensation in f-stops (powers  of
       two).   Only  integer stops are allowed, for efficiency.  The -g option
       specifies a power law for the printer transfer function.   The  default
       gamma  setting  for greyscale printers is 1.0 (linear), and the default
       gamma for color printers is 1.8 (commonly used in prepress).   If  your
       output  seems  to have too much contrast relative to its screen equiva-
       lent, print out the file "ray/lib/lib/gamma.hdr" to your printer  with-
       out  any  gamma correction and using the -d option to set the dots-per-
       inch (see below).  The best match between the small lines and the  grey
       patch  next to it indicate the approximate gamma of your printer, which
       you should use with the -g option for  best  contrast  reproduction  in
       subsequent conversions.

       The  standard  print  area  assumes 8.5 by 11 inch (U.S. letter) paper,
       with 0.5 inch margins on all sides.   The  image  will  be  rotated  90
       degrees  if it fits better that way in the available print area, and it
       will always be centered on the page.  The -p and -m options to  control
       the  paper  size  and  margins,  respectively.   The argument to the -p
       option is the common name for a given paper size, or WWxHH, where WW is
       the width (in inches) and HH is the height.  If millimeters or centime-
       ters are the preferred measurement unit, the 'x' may be replaced by 'm'
       or  'c', respectively.  The WW and HH values are decimal quantities, of
       course.  The current paper identifiers understood by the program may be
       discovered  by  giving  a  0  argument to the -p option.  They are cur-
       rently:

       _Name________Width_Height_(inches)
       envelope      4.12   9.50
       executive     7.25  10.50
       letter        8.50  11.00
       lettersmall   7.68  10.16
       legal         8.50  14.00
       monarch       3.87   7.50
       statement     5.50   8.50
       tabloid      11.00  17.00
       A3           11.69  16.54
       A4            8.27  11.69
       A4small       7.47  10.85
       A5            6.00   8.27
       A6            4.13   6.00
       B4           10.12  14.33
       B5            7.17  10.12
       C5            6.38   9.01
       C6            4.49   6.38
       DL            4.33   8.66
       hagaki        3.94   5.83

       The paper size name may be abbreviated with three or more letters,  and
       character case is ignored.  The argument to the -m option is the margin
       width, which is 0.5 inches by  default.   A  millimeter  or  centimeter
       quantity  may  be  given instead of inches by immediately following the
       value with a 'm' or  'c'  character,  respectively.   (Leave  no  space
       between  the quantity and its unit letter.)  If you wish to specify the
       horizontal and  vertical  margins  separately,  use  the  -mh  and  -mv
       options, instead.

       The  -d option may be used to explicitly set the print density (in dots
       per inch).  If the input picture is lower resolution than  the  printer
       and  has  square  pixels, then ra_ps will adjust the image size so that
       pixels map to dot regions exactly.  This may improve the appearance  of
       fine  detail,  and  may  speed  up the printing process as well, at the
       expense of a slightly smaller image area.   If  you  wish  to  maximize
       print  area  and  the  input image contains no fine detail, then do not
       specify this option.

       The output from ra_ps is designed to be compatible  with  the  Encapsu-
       lated  PostScript  standard, which means that the resulting file may be
       incorporated into documents by page layout programs that  can  read  in
       EPS  files.  Unfortunately, there is currently no option for generating
       a preview bitmap, so the image will show up on the screen as a  rectan-
       gular  area  only.   To control the EPS image size directly, use the -p
       option as explained above with the WWxHH specification, and set -m 0 to
       turn off the margins.

AUTHOR

       Greg Ward

SEE ALSO

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

RADIANCE                            8/28/98                           RA_PS(1)