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.TH PNG 5 "December 3, 2004"
.SH NAME
png \- Portable Network Graphics (PNG) format
.SH DESCRIPTION
PNG (Portable Network Graphics) is an extensible file format for the
lossless, portable, well-compressed storage of raster images. PNG provides
a patent-free replacement for GIF and can also replace many
common uses of TIFF. Indexed-color, grayscale, and truecolor images are
supported, plus an optional alpha channel. Sample depths range from
1 to 16 bits.
.br

PNG is designed to work well in online viewing applications, such as the
World Wide Web, so it is fully streamable with a progressive display
option. PNG is robust, providing both full file integrity checking and
fast, simple detection of common transmission errors. Also, PNG can store
gamma and chromaticity data for improved color matching on heterogeneous
platforms.

.SH "SEE ALSO"
.IR libpng(3), zlib(3), deflate(5), and zlib(5)
.LP
PNG specification (second edition), November 2003:
.IP
.br
  <http://www.w3.org/TR/2003/REC-PNG-20031110/
PNG 1.2 specification, July 1999:
.IP
.br
http://www.libpng.org/pub/png
.LP
PNG 1.0 specification, October 1996:
.IP
.br
RFC 2083
.IP
.br
ftp://ds.internic.net/rfc/rfc2083.txt
.br
or (as a W3C Recommendation) at
.br
http://www.w3.org/TR/REC-png.html
.SH AUTHORS
This man page: Glenn Randers-Pehrson
.LP
Portable Network Graphics (PNG) Specification (Second Edition)
Information technology - Computer graphics and image processing -
Portable Network Graphics (PNG): Functional specification.
ISO/IEC 15948:2003 (E) (November 10, 2003): David Duce and others.
.LP
Portable Network Graphics (PNG) Specification Version 1.2 (July 8, 1999):
Glenn Randers-Pehrson and others (png-list).
.LP
Portable Network Graphics (PNG) Specification Version 1.0 (October 1, 1996):
Thomas Boutell and others (png-list).
.LP


.SH COPYRIGHT NOTICE
.LP
This man page is Copyright (c) 1998-2004 Glenn Randers-Pehrson.  See png.h
for conditions of use and distribution.
.LP
The PNG Specification (Second Edition) is
Copyright (c) 2003 W3C. (MIT, ERCIM, Keio), All Rights Reserved.
.LP
The PNG-1.2 specification is copyright (c) 1999 Glenn Randers-Pehrson.
See the specification for conditions of use and distribution.
.LP
The PNG-1.0 specification is copyright (c) 1996 Massachusetts Institute of
Technology.  See the specification for conditions of use and distribution.
.LP
.\" end of man page