Yeah, that's what I meant by "not ready for release"...

But once you'd look into .txt file that first program creates, you'll figure it out. It won't be hard to create your own .txt

Possible values:

blend_op=SRCE
blend_op=OVER

dispose_op=NONE
dispose_op=PREV
dispose_op=ZERO

Already did, but I don't have it working yet (due to palette issues). I've got the images in layers in gimp, but to quantize the image, I have to flatten it so that all the images are in a single layer, then open it in RIOT and use xiaolin wu or neuquant quantizations. Then I have to throw it all back together with the new palette. It would be so much easier if gimp had image quantization options (actually, if ANY image editor had image quantization options). Every time I use GIMP's median quantization, I end up with less than 256 colors and the major colors usually change.

Maybe use some of the GIF Animator programs (there are lots of them out there), they know how to fit everything into one palette. It's like their basic function.

I'm using Paint Shop Pro 8 and in addition to the Optimized Median Cut color reducing algorithm it has Optimized Octree. One of those usually produces a pretty good result and uses the full 256 Colors (or less if you choose to).

So I found ximatic photoshop plugin, which has virtually every quantization method, however does not actually change the bit depth in gimp, or in multiple layers. Unfortunately, the workaround for me is to get the entire image in an image strip, quantize the image strip, then assemble it back into layers manually.
Here's the image strip with Wu quantization and 255 colors.

I can't quite get paletted alpha transparency to work in anything (I don't have opera right now to test that out), but obviously firefox doesn't work, and XnView is displaying messed up palettes and isn't actually blending over, just replacing it with a transparent layer.

This sort of thing makes me seriously hope that a new format (or old one like mng) will eventually become the standard in lossless layered images, without any buggy implementation.

Thanks for the program though, I managed to get my avatar from ~20 kB gif without a transparent background to a transparent background apng at 20815 B, then compress it down to 20240 B with your program + pngout. It may not seem like a lot, but when fighting that 20 kB limit on avatars, it's useful.

Working with image strips like that = pain in the ass.

You should really experiment with different GIF animators, find the one that offers the best quantization method (and could specify the transparency), then use gif2apng, then optimize that apng.

The real optimization obstacle here is Firefox, I really hope 3.6.7 will fix this annoying bug. It should be released this month, after that you would be able to optimize your animation to 16k easily.

And I already wrote XnView author about that blending problem, he promised to fix it.

There are literally SO many gif animators out there, and only one I could find even mentions quantization (it's a photoshop plugin which isn't free) that I don't think it's even worth it. I think it would be better to get a program which converts image strips into individual frames and vice versa.

http://tools.dynamicdrive.com/imageoptimizer/ worked to get Starblue's dancing signature down to under 20KB, albeit it had to drop the bitdepth a little. You may want to click "show all results".

An online image optimizer has no hope of beating my optimizations.

Maybe they don't mention it, but I'm sure they include it, it's the most important part.

I'd think they'd mention which type of quantization they use, or the methods available. I've tried out ulead gif animator and easy gif animator. Both obviously use quantization, but don't make it clear which type they use at all.

Post has been edited 1 time(s), last time on Jul 12 2010, 8:25 pm by rockz.

Take a look at ImageMagick

It's open source, and their quantization algorithm is fully documented:
http://www.imagemagick.org/script/quantize.php

Or you can use it for cropping your image strip into individual tiles:
http://www.imagemagick.org/Usage/crop/#crop_tile

It uses transparency to optimize the frames, in version 1.4 :

https://sourceforge.net/projects/gif2apng/files/

Wait, there's another animated image format? News to me.

There is, it's just not supported by any browser other than Firefox since...well... Mozilla developed it. And it got rejected as an industry standard.

But then again you should all be using Firefox anyways

This.

Devilesk should make all his animated sigs/avatars in apng. That way, only cool people that use Firefox can see them.

Yeah, aPNG is somewhat unofficial, the "official" animated PNG is MNG, but it's not heavily supported right now.

Opera has had apng support much longer than firefox, and does a better job at it too.

mng support was removed from FF in 2.0 I think. Apparently mng is incredibly complex for an image format, and filled with useless crap. I can't get gimp to save them correctly.

The reason apng was rejected was because mng was there, and because png was "designed" to be a single image, always.

My avatar is now an apng, so anyone using chrome doesn't see it animated. The cybernetics core and supply depot on the red and orange themes of 5.0 were also apngs.

Yeah, it's been broken for ages. I heard MNG export works under Linux, and it's only broken under Windows. But GIMP team doesn't care for WIndows.

I also tried "official" gif2mng utility ( http://www.libmng.com/download/gif2mng.exe ) from the author of MNG, but it doesn't work for me either. And it's not even open source.

Could you try it? Maybe it will work for you...

It would be interesting to compare gif2mng and gif2apng.

The difference between gif2apng and gif2mng is that gif2apng actually works. I like apng better as a format, since it's quite versatile and completely replaces gif in every respect. mng would be nicer, but it's confusing, and there are few programs which support it.