Name

       pnmtoddif - Convert a portable anymap to DDIF format

Syntax

       pnmtoddif pnmtoddif [-resolution x y] [pnmfile [ddiffile]]

OPTIONS

       resolution x y The  horizontal  and vertical resolution of the output image in dots per inch. Defaults to
                      78 dpi.

       pnmfile        The filename for the image file in pnm format.  If this argument is omitted, input is read
                      from stdin.

       ddiffile       The filename for the image file to be  created  in  DDIF  format.   If  this  argument  is
                      omitted, the ddiffile is written to standard output. It can only specified if a pnmfile is
                      also specified.

DESCRIPTION

       pnmtoddif  takes a portable anymap from standard input and converts it into a DDIF image file on standard
       output or the specified DDIF file.

       pbm format (bitmap) data is written as 1 bit DDIF, pgm format data (greyscale) as 8 bit  greyscale  DDIF,
       and ppm format data is written as 8,8,8 bit color DDIF. All DDIF image files are written as uncompressed.
       The data plane organization is interleaved by pixel.

       In addition to the number of pixels in the width and height dimension, DDIF images also carry information
       about  the  size  that  the image should have, that is, the physical space that a pixel occupies. PBMPLUS
       images do not carry this information, hence it has to be externally supplied.  The default of 78 dpi  has
       the beneficial property of not causing a resize on most Digital Equipment Corporation color monitors.

AUTHOR

       Burkhard Neidecker-Lutz
       Digital Equipment Corporation, CEC Karlsruhe
       neideck@nestvx.enet.dec.com

                                                                                                    pnmtoddif(1)