PNG(5) File Formats and Configurations 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 (Third Edition), June 2025:

https://www.w3.org/TR/2025/REC-png-3-20250624/

PNG Specification (Second Edition), November 2003:

https://www.w3.org/TR/2003/REC-PNG-20031110/

PNG 1.2 Specification, August 1999:

https://www.libpng.org/pub/png/spec/1.2/

PNG 1.1 Specification, December 1998:

https://www.libpng.org/pub/png/spec/1.1/

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 (Third Edition). W3C
Recommendation 24 June 2025: Chris Blume et al.

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), W3C Recommendation 10 November 2003: David Duce et
al.

Portable Network Graphics (PNG) Specification Version 1.2 (11 August
1999): Glenn Randers-Pehrson et al.

Portable Network Graphics (PNG) Specification Version 1.1 (31
December 1998): Glenn Randers-Pehrson et al.

Portable Network Graphics (PNG) Specification Version 1.0. IETF RFC
2083, W3C Recommendation 1 October 1996: Thomas Boutell et al.


July 1, 2025 PNG(5)