This document describes PNG (Portable Network Graphics), an extensible file format for the lossless, portable, well-compressed storage of static and animated raster images. PNG provides a patent-free replacement for GIF and can also replace many common uses of TIFF.

Oct 14, 1996 · PNG 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 for transparency.

Nov 10, 2003 · This document is the 14 October 2003 W3C Recommendation of the PNG specification, second edition. It is also International Standard, ISO/IEC 15948:2003. The two documents have exactly identical content except for cover page and boilerplate differences as appropriate to the two organisations.

Jul 20, 2023 · This repository is for the maintenance of the PNG specification, the second edition of which was jointly published in 2003 by W3C as a W3C Recommendation, and by ISO as an International Standard ISO/IEC 15948:2003 (E) with identical contents.

The full specification of PNG was released under the approval of W3C on 1 October 1996, and later as RFC 2083 on 15 January 1997. The specification was revised on 31 December 1998 as version 1.1, which addressed technical problems for gamma and color correction.

PNG is a very widely deployed, lossless, raster image format for RGB and grayscale images, with or without an alpha channel. The First Edition was published as W3C Recommendation in 1996 and the Second Edition in 2003, also published as ISO/IEC 15948:2003. This explainer covers solely changes for the Third Edition, currently under development.

Feb 13, 2025 · PNG Third Edition adds support for CICP metadata. The widely used library libpng supports CICP in PNG (both reading and writing) as of varsion 1.6.45.

Sep 29, 2011 · PNG Specification, joint W3C and ISO/IEC version PNG Extensions and Register. All PNG 1.x versions, including the joint ISO/IEC International Standard and W3C "Second Edition," are backward and forward compatible. There are currently no plans for a …

This document describes PNG (Portable Network Graphics), an extensible file format for the lossless, portable, well-compressed storage of static and animated raster images. PNG provides a patent-free replacement for GIF and can also replace many common uses of TIFF.

May 7, 2024 · Format Description for PNG -- Defines both a datastream and an associated file format for a lossless, portable, compressed, raster (bit-mapped) image. Non-proprietary, open standard from W3C.