b98681b49a
fixed Cygwin+MSVC build errors. The ICC profile handling now includes more checking. Several errors that caused rejection of the profile are now handled with a warning in such a way that the invalid profiles will be read by default in release (but not pre-RC) builds but will not be written by default. The easy part of handling a cHRM chunk is written, where the ICC profile contains the required data. The more difficult part plus guessing a gAMA value requires code to pass selected RGB values through the profile.
75 lines
2.4 KiB
Groff
75 lines
2.4 KiB
Groff
.TH PNG 5 "September 4, 2012"
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.SH NAME
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png \- Portable Network Graphics (PNG) format
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.SH DESCRIPTION
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PNG (Portable Network Graphics) is an extensible file format for the
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lossless, portable, well-compressed storage of raster images. PNG provides
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a patent-free replacement for GIF and can also replace many
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common uses of TIFF. Indexed-color, grayscale, and truecolor images are
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supported, plus an optional alpha channel. Sample depths range from
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1 to 16 bits.
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.br
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PNG is designed to work well in online viewing applications, such as the
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World Wide Web, so it is fully streamable with a progressive display
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option. PNG is robust, providing both full file integrity checking and
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fast, simple detection of common transmission errors. Also, PNG can store
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gamma and chromaticity data for improved color matching on heterogeneous
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platforms.
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.SH "SEE ALSO"
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.BR "libpng"(3), " libpngpf"(3), " zlib"(3), " deflate"(5), " " and " zlib"(5)
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.LP
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PNG specification (second edition), November 2003:
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.IP
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.br
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<http://www.w3.org/TR/2003/REC-PNG-20031110/
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PNG 1.2 specification, July 1999:
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.IP
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.br
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http://www.libpng.org/pub/png
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.LP
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PNG 1.0 specification, October 1996:
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.IP
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.br
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RFC 2083
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.IP
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.br
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ftp://ds.internic.net/rfc/rfc2083.txt
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.br
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or (as a W3C Recommendation) at
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.br
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http://www.w3.org/TR/REC-png.html
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.SH AUTHORS
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This man page: Glenn Randers-Pehrson
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.LP
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Portable Network Graphics (PNG) Specification (Second Edition)
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Information technology - Computer graphics and image processing -
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Portable Network Graphics (PNG): Functional specification.
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ISO/IEC 15948:2003 (E) (November 10, 2003): David Duce and others.
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.LP
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Portable Network Graphics (PNG) Specification Version 1.2 (July 8, 1999):
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Glenn Randers-Pehrson and others (png-list).
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.LP
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Portable Network Graphics (PNG) Specification Version 1.0 (October 1, 1996):
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Thomas Boutell and others (png-list).
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.LP
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.SH COPYRIGHT NOTICE
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.LP
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This man page is Copyright (c) 1998-2006 Glenn Randers-Pehrson. See png.h
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for conditions of use and distribution.
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.LP
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The PNG Specification (Second Edition) is
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Copyright (c) 2003 W3C. (MIT, ERCIM, Keio), All Rights Reserved.
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.LP
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The PNG-1.2 specification is copyright (c) 1999 Glenn Randers-Pehrson.
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See the specification for conditions of use and distribution.
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.LP
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The PNG-1.0 specification is copyright (c) 1996 Massachusetts Institute of
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Technology. See the specification for conditions of use and distribution.
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.LP
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.\" end of man page
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