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 <oeriksson@mandriva.com> 2:1.2.43-1mdv2010.1
+ Revision: 511259
- use a newer apng patch from upstream
- 1.2.43
* Wed Feb 24 2010 Oden Eriksson <oeriksson@mandriva.com> 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.

I installed that apng in my FF toolbar but I can't figure out how it works....Maybe a small tute on this would help sometime in the future.

There is a little bit of a tutorial here plus a screen shot.

Each layer of your animation needs to be made into a separate png image.

Thanks "O" I will bookmark this link...

This APNG plugin for GIMP is supposed to do just that.

At this point, I'm convinced there is an incompatibility with the version of libpng Fedora uses and the GIMP-APNG plugin. I have no idea which version of libpng might be supported by the GIMP-APNG plugin and no answer or documentation regarding that has yet been provided by the developer.

Regular PNG images save fine but I get this error when trying to save an animated APNG.

libpng error: width and/or height in the first frame's fcTL don't match the ones in IHDR

This tells me the image data (png chunk) is not being passed over properly to the patched libpng from the GIMP-APNG plugin.

I have posted to source forge regarding the error and I may contact the plugin developer directly to see if I can get clarification on which versions of libpng+libpng-patch are supported by this plugin.

Ok, it turns out that the error message I was getting was due to the fact that the top layer in my layer dialog was not the same size as the overall image.

From the developer..

Once I resized the top layer to the image size, I was able to save as an APNG.

I am also able to load back in animated PNGs with all layers intact. Still need to do some more testing but so far so good..

Here is one of my Tux animations saved as an animated PNG.

has .apng extension


has .png extension


So, who can see it animated and who can't?

I'm not sure which browsers other than Forefox and Opera support APNGs.

I'll start a thread on how to patch and compile libpng + how to compile the GIMP-APNG plugin in Linux.

I can see the cute little bird and also the fish jumping. Tell them to syncronize themselves so I can compare them.

Molly, the only differences between those images are the file extensions. I was wondering if the browser looked at the extension and treated the files differently based on their extension.

Interestingly enough in Firefox, when I right click on the APNG image and view image, it asks me to save it as a bin file. I can right click and view the PNG just fine. Looks like Firefox is treating the APNG extension as a binary file, rather than an mime image. Both are animated though.

Hey you must have done something cuz now when I look at the fish they are syncronized. Before, the top one was just a bit ahead of the bottom. Anyway, I was teasing. Who is going to be looking at them bothe at the same time.....

I haven't read the thread completely so may be saying something stupid.

Both Tux images look the same and the top one isn't animated. This is in google chrome.

edit- the bottom one isn't animated either, but I figured since it was .png it couldn't be?

There is a plugin for animated png images. Both those images are animated png images. If you don't see the animation it must be your browser that is not able to view them as animated png images.