NAME

       ppmntsc - make a portable pixmap look like taken from an American TV

SYNOPSIS

       ppmntsc  [  --pal  ] [ --legalonly ] [ --illegalonly ] [ --correctedonly ] [ --verbose ] [
       --debug ] [ infile ]

       Minimum unique abbreviations of options are acceptable.

DESCRIPTION

       This program makes colors legal in  the  NTSC  (or  PAL)  color  systems.   Often,  images
       generated  on  the  computer  are  made for use in movies which ultimately end up on video
       tape.  However, the range of colors (as specified by their RGB values) on a computer  does
       not match the range of colors that can be represented using the NTSC (or PAL) systems.  If
       an image with "illegal" colors is sent directly to an  NTSC  (or  PAL)  video  system  for
       recording,  the  "illegal"  colors  will  be  clipped.   This may result in an undesirable
       looking picture.

       This utility tests each pixel in an image to see if it falls within  the  legal  NTSC  (or
       PAL)  range.   If not, it raises or lowers the pixel's saturation in the output so that it
       does fall within legal limits.  Pixels that are already OK just  go  unmodified  into  the
       output.

       Input  is from the file named input.  If input is -, input is from Standard Input.  If you
       don't specify input, input is from Standard Input.

       Output is always to Standard Output.

       This program handles multi-image PPM input, producing multi-image PPM output.

OPTIONS

       --pal  Use the PAL transform instead of the default NTSC.

       --verbose
              Print a grand total of the number of illegal pixels.

       --debug
              Produce a humongous listing of illegal colors and their legal counterparts.   NOTE:
              This option may produce a great deal of output.

       --legalonly
              Output  only  pixels  that are already legal.  Output black in place of pixels that
              are not.

       --illegalonly
              Output only pixels that are illegal (and output them uncorrected).  Output black in
              place of pixels that are already legal.

       --correctedonly
              Output  only pixels that are corrected versions of illegal pixels.  Output black in
              place of pixels that are already legal.

SEE ALSO

       ppm(5), ppmdepth(1), ppmdim(1), ppmbrighten(1)

AUTHOR

       Wes Barris, Minnesota Supercomputer Center, Inc., Bryan Henderson