pamtotga



Pamtotga User Manual(0)                                Pamtotga User Manual(0)




NAME

       pamtotga - convert a Netpbm image to a TrueVision Targa file



SYNOPSIS

       pamtotga [-mono|-cmap|-rgb] [-norle] [pamfile]

       All  options  can  be abbreviated to their shortest unique prefix.  You
       may use two hyphens instead of one to designate an option.  You may use
       either  white  space  or  equals  signs  between an option name and its
       value.



DESCRIPTION

       This program is part of Netpbm(1).

       pamtotga reads a PBM, PGM, PPM, or PAM image as input  and  produces  a
       TrueVision  Targa  file  as  output.   The  PAM  image  may be either a
       BLACKANDWHITE, GRAYSCALE, RGB, or RGB_ALPHA image.

       To create a TGA image with transparency (i.e. with an alpha mask),  use
       RGB_ALPHA  PAM  input.   Some Netpbm programs that generate images with
       alpha masks generate them in that format.  For another  way  to  create
       the proper input stream, see pamstack(1).

       It  is  unclear  that  anything  except  pamtotga knows about TGAs with
       transparency.  The history behind  this  feature  of  pamtotga  is  not
       clear.   The format pamtotga produces is simply the same as an ordinary
       RGB TGA image except with a 4th plane added for transparency.  The Pix-
       elSize  field of the TGA header specifies 32 bits instead of 24 and the
       raster has an extra byte added to each pixel, at  the  tail  end.   The
       value  of  that byte has the same meaning as in a PAM image with maxval
       255.



OPTIONS

       -cmap  Make output Targa file of type 24 bit colormapped.   Input  must
              contain no more than 256 distinct colors.


       -mono  Make  output Targa file of type 8 bit monochrome.  Input must be
              PBM or PGM or a PAM with BLACKANDWHITE or GRAYSCALE tuple  type.
              See -cmap.

              You  may  specify at most one of -mono, -cmap, and -rgb.  If you
              specify neither, the default image type is the most highly  con-
              strained  compatible type is used, where monochrome is more con-
              strained than colormapped which is in turn more constrained than
              unmapped.


       -rgb   Make  output  Targa  file  of  type  24 bit unmapped color.  See
              -cmap.


       -norle Do not use run-length encoding in the output Targa  file.   Run-
              length  encoded  files are smaller, but Some Targa readers can’t
              read run-length encoded files.





SEE ALSO

       tgatoppm(1), pnmquant(1), pamstack(1), pam(1) pnm(1)



HISTORY

       This program was called ppmtotga until Netpbm 10.6 (July  2002).   That
       was always a misnomer, though, because a PPM class program would not be
       able to tell the difference between PGM and PPM  input  (it  would  all
       look  like  PPM), and thus could not choose the output Targa image type
       based on the type of the input.  Netpbm 10.6 also added the ability  to
       handle an alpha channel, so it became a PAM class program.

       In  Netpbm  10.15  (April  2003),  the  program became the first in the
       Netpbm package to recognize an alpha channel in a PAM.   It  recognized
       tuple  type ’RGBA’.  But when this kind of PAM image was later added to
       the PAM specification, it was specified with  tuple  type  ’RGB_ALPHA’.
       So  in  Netpbm  10-26  (January  2005),  pamtotga  changed to recognize
       ’RGB_ALPHA’ instead of ’RGBA’.



AUTHOR

       Copyright (C) 1989, 1991 by Mark Shand and Jef Poskanzer.



netpbm documentation             21 July 2002          Pamtotga User Manual(0)

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