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PNG(5) FreeBSD File Formats Manual PNG(5)
NAME
png - Portable Network Graphics (PNG) format
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.
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.
SEE ALSO
libpng(3), zlib(3), deflate(5), and zlib(5)
PNG Specification (Second Edition), November 2003:
https://www.w3.org/TR/2003/REC-PNG-20031110/
PNG 1.2 Specification, July 1999:
https://png-mng.sourceforge.io/pub/png/spec/1.2/
PNG 1.0 Specification, October 1996:
RFC 2083
https://www.ietf.org/rfc/rfc2083.txt
or W3C Recommendation
https://www.w3.org/TR/REC-png-961001
AUTHORS
This man page: Glenn Randers-Pehrson, Cosmin Truta
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.
Portable Network Graphics (PNG) Specification Version 1.2 (July 8,
1999): Glenn Randers-Pehrson and others.
Portable Network Graphics (PNG) Specification Version 1.0 (October 1,
1996): Thomas Boutell and others.
February 23, 2024 PNG(5)