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diff --git a/share/man/man5/pbm.5 b/share/man/man5/pbm.5 new file mode 100644 index 000000000000..55d2c5c1be39 --- /dev/null +++ b/share/man/man5/pbm.5 @@ -0,0 +1,88 @@ +.\" +.\" $FreeBSD$ +.\" +.Dd September 27, 1991 +.Dt PBM 5 +.Os +.Sh NAME +.Nm pbm +.Nd portable bitmap file format +.Sh DESCRIPTION +The portable bitmap format is a lowest common denominator monochrome +file format. +It was originally designed to make it reasonable to mail bitmaps +between different types of machines using the typical stupid network +mailers we have today. +Now it serves as the common language of a large family of bitmap +conversion filters. +The definition is as follows: +.Pp +.Bl -bullet -compact +.It +A "magic number" for identifying the file type. +A pbm file's magic number is the two characters "P1". +.It +Whitespace (blanks, TABs, CRs, LFs). +.It +A width, formatted as ASCII characters in decimal. +.It +Whitespace. +.It +A height, again in ASCII decimal. +.It +Whitespace. +.It +Width * height bits, each either '1' or '0', starting at the top-left +corner of the bitmap, proceeding in normal English reading order. +.It +The character '1' means black, '0' means white. +.It +Whitespace in the bits section is ignored. +.It +Characters from a "#" to the next end-of-line are ignored (comments). +.It +No line should be longer than 70 characters. +.El +.Pp +Here is an example of a small bitmap in this format: +.Bd -literal +P1 +# feep.pbm +24 7 +0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 +0 1 1 1 1 0 0 1 1 1 1 0 0 1 1 1 1 0 0 1 1 1 1 0 +0 1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 1 0 +0 1 1 1 0 0 0 1 1 1 0 0 0 1 1 1 0 0 0 1 1 1 1 0 +0 1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 +0 1 0 0 0 0 0 1 1 1 1 0 0 1 1 1 1 0 0 1 0 0 0 0 +0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 +.Ed +.Pp +Programs that read this format should be as lenient as possible, +accepting anything that looks remotely like a bitmap. +.Pp +There is also a variant on the format, available +by setting the RAWBITS option at compile time. +This variant is +different in the following ways: +.Pp +.Bl -bullet -compact +.It +The "magic number" is "P4" instead of "P1". +.It +The bits are stored eight per byte, high bit first low bit last. +.It +No whitespace is allowed in the bits section, and only a single character +of whitespace (typically a newline) is allowed after the height. +.It +The files are eight times smaller and many times faster to read and write. +.El +.Sh AUTHORS +Copyright (C) 1989, 1991 by +.An Jef Poskanzer . +.\" Permission to use, copy, modify, and distribute this software and its +.\" documentation for any purpose and without fee is hereby granted, provided +.\" that the above copyright notice appear in all copies and that both that +.\" copyright notice and this permission notice appear in supporting +.\" documentation. This software is provided "as is" without express or +.\" implied warranty. |