PNG Reference Library: libpng

This is an open source project to develop and maintain the reference library for use in applications that read, create, and manipulate PNG (Portable Network Graphics) raster image files.

The primary web site for PNG is www.libpng.org/pub/png.

The primary public ftp site for libpng is
ftp://ftp-osl.osuosl.org/pub/libpng/src.
This site will also respond to https and http requests:
https://ftp-osl.osuosl.org/pub/libpng/src
http://ftp-osl.osuosl.org/pub/libpng/src
Thanks to the Oregon State University Open Source Laboratory.

The previous ftp site is still being maintained at ftp://ftp.simplesystems.org/pub/png, but the OSUOSL site is much faster and has a more complete archive of old versions.

The ftp site for beta versions of libpng is also at ftp://ftp-osl.osuosl.org/pub/libpng/src/beta.

The current public and beta versions of libpng are also available at https://sourceforge.net/project/showfiles.php?group_id=5624.

There are pointers to various distributions of libpng and SHA checksums here.

You can receive notifications of libpng releases through release-monitoring.org, at release-monitoring.org/projects/search/?pattern=libpng.

The Sourceforge project page for libpng is at https://sourceforge.net/projects/libpng/.

A Git repository for libpng is available. You can access it at GitHub (github.com/pnggroup/libpng) or at SourceForge (sourceforge.net/p/libpng/code). At present, there are eight branches:

• master (actively developed)
• libpng16 (equivalent to master)
• libpng17 (frozen, last updated on 2017-Sep-03)
• libpng15 (frozen, last updated on 2017-Sep-28)
• libpng14 (frozen, last updated on 2017-Sep-28)
• libpng12 (frozen, last updated on 2017-Sep-28)
• libpng10 (frozen, last updated on 2017-Aug-24)
• libpng00 (frozen, last updated on 1998-Mar-08)

Starting from version 1.6.42 onwards, the release tags are GPG-signed. The public signature key is available here: github.com/ctruta.gpg.

A Doxygen index for various releases is available at fossies.org/libpng.

An ABI compatibility analysis of libpng releases is available at abi-laboratory.

A Coverity project for libpng is at https://scan.coverity.com/projects/4061. The project is set up to scan the head of each of the libpng10 through libpng17 branches; libpng00 is not included.

The mailing list for libpng developers and developers of libpng-based applications is png-mng-implement (at) lists.sourceforge.net. Visit http://png-mng.sourceforge.net/pub/png/pngmisc.html#lists to subscribe. (archived here).

Bug reports can be sent to the mailing list or submitted via the SourceForge Bug tracker (select the "Create Ticket" button) or as an issue at GitHub.

If you wish to privately report a security issue (vulnerability) in libpng, please report it by email to png-mng-security at lists.osuosl.org, where it will be seen by a small group of long-time libpng contributors. You don't need to subscribe (in fact you probably won't be allowed to subscribe) to that list.

Feel free to download and use the official PNG logo (size 88x31) with your application documentation and web pages:

This site belongs to the PNG Development Group and is maintained for the group by Cosmin Truta.

Web space for this project is being provided by sourceforge.net.