Pamtotga User Manual(0) Pamtotga User Manual(0)NAMEpamtotga - convert a Netpbm image to a TrueVision Targa file
SYNOPSISpamtotga [-mono|-cmap|-rgb] [-norle] [-name=name [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.
-name=name
This is the value for the image ID stated in the header of the
TGA output file. pamtotga truncates it as necessary to meet TGA
standards.
By default, pamtotga uses the input file name argument, up to
the first period (or the whole thing if there is no period). It
truncates it as necessary to meet TGA standards. If you specify
(or default to) Standard Input, pamtotga omits the image ID from
the TGA header.
SEE ALSOtgatoppm(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 12 June 2008 Pamtotga User Manual(0)
