Editing PNG (section)

=== Animation ===
[[File:Animated PNG example bouncing beach ball.png|thumb|An APNG (animated PNG) file (displays as static image in [[Comparison of web browsers#Image format support|some web browsers]])]]
The core PNG format does not support animation. [[Multiple-image Network Graphics|MNG]] is an extension to PNG that does; it was designed by members of the PNG Group. MNG shares PNG's basic structure and chunks, but it is significantly more complex and has a different file signature, which automatically renders it incompatible with standard PNG decoders. This means that most web browsers and applications either never supported MNG or dropped support for it.

The complexity of MNG led to the proposal of [[APNG]] by developers at the Mozilla Foundation. It is based on PNG, supports animation and is simpler than MNG. APNG offers fallback to single-image display for PNG decoders that do not support APNG. Today, the APNG format is supported by all major web browsers.<ref>{{Cite web|title=Can I use... Support tables for HTML5, CSS3, etc|url=https://caniuse.com/apng|access-date=2021-02-06|website=caniuse.com}}</ref> APNG is supported in [[Mozilla Firefox|Firefox]] 3.0 and up, [[Pale Moon (web browser)|Pale Moon]] (all versions), and [[Safari (web browser)|Safari]] 8.0 and up.<ref>{{cite web |date=2014-09-17 |title=iOS 8 and iPhone 6 for web developers and designers: next evolution for Safari and native webapps |url=http://www.mobilexweb.com/blog/safari-ios8-iphone6-web-developers-designers |access-date=2014-09-24 |publisher=mobilexweb.com}}</ref> Chromium 59.0 added APNG support,<ref>{{cite web|url = https://chromium.googlesource.com/chromium/src/+/7d2b8c45afc9c0230410011293cc2e1dbb8943a7|title = chromium / chromium / src / 7d2b8c45afc9c0230410011293cc2e1dbb8943a7|access-date = 31 March 2017|author=scroggo|work = chromium.googlesource.com|date = 14 March 2017}}</ref><ref>{{cite web|url = https://chromium.googlesource.com/chromium/src/+log/59.0.3047.0..59.0.3053.0?pretty=fuller&n=10000|title = chromium / chromium / src / 59.0.3047.0..59.0.3053.0|access-date = 31 March 2017|author=chrome-cron|display-authors=etal|work = chromium.googlesource.com|date = 27 March 2017}}</ref> followed by Google Chrome. [[Opera (web browser)|Opera]] supported APNG in versions 10–12.1, but support lapsed in version 15 when it switched to the [[Blink (browser engine)|Blink]] rendering engine; support was re-added in Opera 46 (inherited from Chromium 59).<ref>{{Cite web |title=Dev.Opera — What's new in Chromium 59 and Opera 46 |url=https://dev.opera.com/blog/opera-46/ |access-date=2022-09-11 |website=dev.opera.com}}</ref> [[Microsoft Edge]] has supported APNG since version 79.0, when it switched to a Chromium-based engine.

The PNG Group decided in April 2007 not to embrace APNG.<ref>{{cite web|url=http://sourceforge.net/mailarchive/message.php?msg_name=3.0.6.32.20070420132821.012dd8e8%40mail.comcast.net|title=Vote failed: APNG 20070405a|date=20 April 2007|url-status=dead|archive-url=https://web.archive.org/web/20080203042347/http://sourceforge.net/mailarchive/message.php?msg_name=3.0.6.32.20070420132821.012dd8e8%40mail.comcast.net|archive-date=3 February 2008}}</ref> Several alternatives were under discussion, including ANG, aNIM/mPNG, "PNG in GIF" and its subset "RGBA in GIF".<ref>{{cite web|url=http://gjuyn.xs4all.nl/pnganim.html|archive-url=https://web.archive.org/web/20090124013928/http://gjuyn.xs4all.nl/pnganim.html|title=PNG Group animation proposal comparison + test-software|archive-date=24 January 2009|work=xs4all.nl}}</ref> However, currently only APNG has widespread support.

With the development of the Third Edition of the PNG Specification, now maintained by the PNG working group,<ref>{{Cite web |date=2023-05-24 |title=PNG Third Edition, Explained |url=https://github.com/w3c/PNG-spec/blob/d5b059ad7f81e789b7689f1c0479db8d1cb41fb8/Third_Edition_Explainer.md#apng |website=W3C GitHub}}</ref> APNG will finally be incorporated into the specification as an extension.<ref>{{Cite web |date=2023-09-21 |title=PNG Specification (Third Edition), APNG: frame-based animation |url=https://www.w3.org/TR/png/#apng-frame-based-animation |website=w3.org}}</ref>