Here is the URL but what you do with it I don't know.

http://registry.gimp.org/node/24394

That's the source code. You'll need to compile it using the same steps you used to compile Gimp-Gap.

As normal user
1) ./configure (configure options for compiling)

2) make (compile and link)

As root
3) make install (install application and data)

Since you've already compiled Gimp-Gap, you should have all of the development tools and libs needed to compile this.

I'd really like to work with APNGs so I plan on compiling this and checking it out.

This is a message in terminal at the end of the compile ./configure attempt.

checking for png_get_acTL in -lpng... no
configure: error: PNG library doesn't have APNG support

Which step gave you this message? ./configure ?

Yes. Meant to say configure, not compile up there. Urg.

Looks like you might need to patch or update libpng. Let me check to see what is out there..

Do you have libpng-devel-2:1.2.43-1.fc12 installed? If not, install it and run ./configure again..

Setting up Install Process
No package libpng-devel-2:1.2.43-1.fc12 available.
Nothing to do

Please check under System/Administration/Add/Remove Software to see if libpng-devel is installed.

Yep, it is.




Strange it would say it's not available instead of already installed.

Unfortunately, I don't see anything in this changelog that denotes that the libpng-devel for F12 has been patched to support APNG.

Looks like we will have to manually patch that devel lib to support apng (or find a pre-patched version).

Here's the patch.

I can follow up on this later today..

OK.

I've had a chance to delve into this a little further and there is no patch for libpng-1.2.43 on the Source Forge page. It goes from libpng-1.2.42rc3 right to libpng-1.4.0.

Looking at other distros, I see where Mandriva has incorporated some kind of patch for libpng-1.2.43 into their RPMs.

From Changelog..

* Thu Feb 25 2010 Oden Eriksson <[email protected]> 2:1.2.43-1mdv2010.1
+ Revision: 511259
- use a newer apng patch from upstream
- 1.2.43
* Wed Feb 24 2010 Oden Eriksson <[email protected]> 2:1.2.42-1mdv2010.1
+ Revision: 510653
- 1.2.42
- rediffed the apng patch

Who knows what they did or where they got this "newer apng patch"?

There are several development packages that are dependent on libpng so I'm a little leery about doing anything with it at this point. I recommend waiting for Fedora to patch libpng before using this apng plugin. Then again, it may be a long wait being they are still using this version of libpng in the upcoming release of F13.

Perhaps I'll post over on FF (for all the good it will do) and see if I can get some more info.

One would think this would be the hot new thing but there doesn't seem to be much interest in apng at this point.

Bummer. I'd think everyone would be very excited about it. I know I am.

Thanks for trying, GnuTux.

Ok, I found the proper APNG patch for libpng in Fedora 12. I was able to patch, compile and install libpng.

Next, I compiled the gimp apng-plugin and installed the executable in the GIMP plugin folder.

This gave me a new extension option in the save dialog: PNG+APNG Image. Choosing this option gives me the standard PNG save dialog, with an additional "animation" check box and a "hide first frame" check box.

So far, so good, right?

However, my attempts at saving a muti-layer image always results in a flattened, single frame PNG.

Another odd thing is the developer didn't choose to use the APNG extension, so there is no automatic selection of this format when adding the .apng extension onto the filename. I think I read in the release notes that he was planning to correct this issue.

Anyway, there is something wrong. I'm thinking the newly patched libpng isn't being loaded at runtime and I'm still using the old libpng. I currently have both libs installed but I've set environment variables that tells the system where to find the new libpng but I'm not so sure that's happening.

I know Fedora caches libs so maybe it's still pulling libpng from cache. Removing or including the environment variables doesn't seem to matter.

I'm still missing something.

This is an apng I made using the Firefox apng add-on. It has a png extension, not apng.

BTW if you download the image, gimp will open it as a single layer image not an animation. Don't know if there's an application except for Ffox that will open it as a multilayered file.



If you are unable to view the image, it may be that your browser does not support apngs.

Hope the developer gets it all fixed so it can be used.

If you are interested in trying out the Firefox APNG Edit add-on, here is a link to the add-on.
https://addons.mozilla.org/en-US/firefox/addon/5519

I can see it using IE, so I would imagine all browsers can see it...since IE is the lamest browser, lol.

You are right but Windows is not the only OS to have bugs




We should be fair IE is not the lamest browser
The Lamest Browser is what use who never update his browser -...i still see messages from peple that complain for png not correctly displayed from IE..that means they never update their browser not even for security fixes in the last 4 years
(because was a problem of IE 6...so long time ago )

LOL, yes if IE was all that awful I wouldn't keep using it...but that being said, even with current updates, sometimes I have to go use my Safari to keep from getting kicked off or viewing some websites.
*must add that my ie just went into spasms trying to look at Jolie's newest vid, it must have opened more than 20 of those 'about:blank' pages and I couldn't turn them off fast enough. Had to go offline, and even that took forever! Grrrr.

It sure isn't but that message was due to the wrong file name being used. If the filename (app) doesn't exist, the message is "not available". If the filename (app) is already installed, the message is "already installed".

Update on my progress: I installed a 3rd party patched libpng and compiled gimp-apng plugin against it but got an apng "sizing" error message when I tried to save an animated png. Doesn't appear that the version of patched libpng is corresponding to the version of gimp apng plugin.

Unless I'm just missing something obvious, it looks like this one may take some code debugging to get it to work properly.