pnmtorle(1) [debian man page]
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 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 pip- ing 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. SEE ALSO
rletopnm(1), urt(1), RLE(5). AUTHOR
Wes Barris Army High Performance Computing Research Center (AHPCRC) Minnesota Supercomputer Center, Inc. 1 March 31, 1994 PNMTORLE(1)
Check Out this Related Man Page
giftopnm(1) General Commands Manual giftopnm(1) NAME
giftopnm - convert a GIF file into a portable anymap SYNOPSIS
giftopnm [--alphaout={alpha-filename,-}] [-verbose] [-comments] [-image N] [GIFfile] DESCRIPTION
This is a graphics format converter from the GIF format to the PNM (i.e. PBM, PGM, or PPM) format. If the image contains only black and maximally bright white, the output is PBM. If the image contains more than those two colors, but only grays, the output is PGM. If the image contains other colors, the output is PPM. If you have an animated GIF file, you can extract individual frames from it with gifsicle and then convert those using giftopnm. A GIF image contains rectangular pixels. They all have the same aspect ratio, but may not be square (it's actually quite unusual for them not to be square, but it could happen). The pixels of a Netpbm image are always square. Because of the engineering complexity to do oth- erwise, giftopnm converts a GIF image to a Netpbm image pixel-for-pixel. This means if the GIF pixels are not square, the Netpbm output image has the wrong aspect ratio. In this case, giftopnm issues an informational message telling you to run pnmscale to correct the out- put. OPTIONS
--alphaout=alpha-filename giftopnm creates a PGM (portable graymap) file containing the alpha channel values in the input image. If the input image doesn't contain an alpha channel, the alpha-filename file contains all zero (transparent) alpha values. If you don't specify --alphaout, giftopnm does not generate an alpha file, and if the input image has an alpha channel, giftopnm simply discards it. If you specify - as the filename, giftopnm writes the alpha output to Standard Output and discards the image. See pnmcomp(1) for one way to use the alpha output file. -verbose Produce verbose output about the GIF file input. -comments Only output GIF89 comment fields. -image N Output the specified gif image from the input GIF archive (where N is '1', '2', '20'...). Normally there is only one image per file, so this option is not needed. All flags can be abbreviated to their shortest unique prefix. RESTRICTIONS
This does not correctly handle the Plain Text Extension of the GIF89 standard, since I did not have any example input files containing them. SEE ALSO
ppmtogif(1), ppmcolormask(1), pnmcomp(1), gifsicle(1) <http://www.lcdf.org/gifsicle>, ppm(5). AUTHOR
Copyright (c) 1993 by David Koblas (koblas@netcom.com) LICENSE
If you use giftopnm, you are using a patent on the LZW compression method which is owned by Unisys, and in all probability you do not have a license from Unisys to do so. Unisys typically asks $5000 for a license for trivial use of the patent. Unisys has never enforced the patent against trivial users, and has made statements that it is much less concerned about people using the patent for decompression (which is what giftopnm does than for compression. The patent expires in 2003 / 2004, depending on the country. Rumor has it that IBM also owns a patent covering giftopnm. A replacement for the GIF format that does not require any patents to use is the PNG format. 13 January 2001 giftopnm(1)