This program converts Netpbm image files into Utah
image files. You can include an alpha mask. If the input is a multiple
image file, the output consists of several concatenated RLE images.
The RLE file will contain either a three channel color image (24 bits) or
a single channel grayscale image (8 bits) depending upon the pnm file depth.
If a converted ppm is displayed on an 8 bit display, the image must be
dithered. In order to produce a better looking image (on 8 bit displays),
it is recommended that the image be quantizing (to 8 bit mapped color) prior
to its display. This may be done by piping the output of this program into
An example of this is shown later.
This option will cause pnmtorle to operate in verbose mode. The header
information is written to "stderr". Actually, there is not much header
information stored in a Netpbm file, so this information is minimal.
This option allows the header of the Netpbm image to be dumped to "stderr"
without converting the file. It is equivalent to using the -v option except
that no file conversion takes place.
This option causes pnmtorle to include an alpha channel in the output
image. The alpha channel is based on the image: Wherever a pixel
is black, the corresponding alpha value is transparent. Everywhere
else, the alpha value is fully opaque.
If specified, the output will be written to this file. If
outfile is "-", or if it is not specified, the output will be written to the
standard output stream.
The name of the Netpbm image data file to be converted. If not specified,
standard input is assumed.