pnmtorle(1) - phpMan

PNMTORLE(1) General Commands Manual PNMTORLE(1)

NAME
pnmtorle - convert a Netpbm image file into an RLE image file.

SYNOPSIS
pnmtorle [ -h ] [ -v ] [ -a ] [ -o outfile ] [ pnmfile ]

DESCRIPTION
This program converts Netpbm image files into Utah RLE(5) image files. You can include an
alpha mask. If the input is a multiple image file, the output consists of several con-
catenated 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 dis-
played 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 the Utah mcut(1) or rlequant(1) utilities. An example of this is shown
later.

OPTIONS
-v 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.

-h 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.

-a 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.

-o outfile
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.

pnmfile
The name of the Netpbm image data file to be converted. If not specified, standard
input is assumed.

EXAMPLES
pnmtorle -v file.ppm -o file.rle
While running in verbose mode, convert file.ppm to RLE format and store resulting
data in file.rle.

pnmtorle -h file.pgm
Dump the header information of the Netpbm file called file.pgm.