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Presenting APNG: Like MNG, Only Better
An anonymous reader writes "It's fair to say that most people love PNG images (or at least hate GIFs). However, the one advantage GIFs have over PNGs is that they can be animated. There is, of course, an animated version of PNG, MNG, but few programs can view these images (mainly because the MNG decoder is so large that the likes of Mozilla refuse to include it). But there may be an answer coming: Vladimir Vukicevic and Stuart 'Pavlov' Parmenter (of Mozilla fame) have put together a specification for APNG (Animated Portable Network Graphics)." (Read more below.)
"Unlike MNG, APNG is not a separate file format, but rather an extension to PNG. Thus, APNG images are just normal PNG images (with the .png extension) but can be animated. The system is fully backwards-compatable, so any program that can open a PNG image will be able to open an APNG image (though non-APNG viewers will only show the first frame). Vitally, the decoder just adds an extra few kilobytes onto a standard PNG decoder. APNG support is in the process of being checked into Mozilla. Hopefully, other programs will follow suit."
IE won't support it until 2012, and even then, it'll only support half the features.
how soon will such functionality be implented in major graphic manipulation programs like Photoshop?
:P
Oh, and yeah, I'm sure someone will make it work with The Gimp, so don't flog me over that detail.
Join the TWIT army now!
Discussion can be found here: http://bugzilla.mozilla.org/show_bug.cgi?id=257263
Haven't they realised that animated GIFs only serve to irritate?
Well now, this sounds really nice. I have always wondered why MGN never really took off, but then PNG never really took off either (you all know the MSFT story...). Just never knew this had a big-decoder-problem.
So naturally I was disappointed when Mozilla took out MNG support back then, but this seems to make it better (read: more chances of survival in the real world out there) standard, and that is always a good thing.
One more reason to finally get rid of all them GIFs, even if they are no longer patent-encumbered - the format is still not capable of alpha transparency...
the MNG decoder is so large that the likes of Mozilla refuse to include it
Yeah, and a damn good thing too, otherwise we'd have a browser that's so huge and bloated that...
Nevermind...
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
This is probably a stupid question, but what are animated gifs used for besides online ads? It seems to me that the animated gif is now an endangered animal found only in annoying online ads, or annoying web-pages that were put together by someone with a rudimentary knowledge of HTML and a free CD of clip-art (or images that they stole from another unattractive site). I would not be sad to see animated gifs (or apngs) disappear entirely. If someone can post a good use of apgns/gifs for which a better solution does not exist, I will humbly retract my opinion and we can all consider this to be have been, indeed, a stupid question.
Why not? Alpha blending allows web developers to make fine adjustments to page layouts with necessitating the "recutting" of overlapping layers in Photoshop. It also allows for variance in browser layout without causing visible breaks -- thus Mozilla and KDE don't need to render "exactly" like MSIE down to the last pixel in order for layouts to basically look the same.
GIF is gunk. Can we step into the 21st century yet?
// I will show you fear in a handful of jellybeans.
Microsoft recognizes that a new animated image format was needed (after seeing it mentioned on /.). As such they have announced the release of a new standard, Microsoft Extended Sequential Series (MESS).
MESS will be incorporated into Longhorn and will be one of the major enhancements to the Microsoft operating system. The MESS graphics format will permit content providers to render highly complex images on a users system. The MESS format allows use of Active X components which permits all kinds of interesting effects on a users system.
When asked about using existing standards executives at Microsoft responded that no other standard in this area exists. Patents have been applied for covering this novel concept and will be agressively defended. Anyone trying to duplicate the intelectual property of Microsoft would be better off using MESS as long as they pay the royalties due Microsoft or they may find them selves in an even bigger MESS.
Executives were then asked about possible security implications of the new MESS protocol. Executives replied that security is a number one priority and that an updated SP3 patch is currently in the works that will address all security issues. The only thing holding up SP3 release is final release of SP2 patch 1 that is needed to address security issues caused by various linux distributions.
16,777,216 != infinity :-)
:)
Actually, there is no point getting an infinite number of colours because:
1) Most displays cannot show that many colour
2) Even with a display that does 16 777 216 colours, the human eye cannot distinguish between that many shades (particularly in the blue region) which is why 16 bit colour (which has 5 + 6 + 5 bits to divide amongst the red, green & blue) puts the extra information into the green (I think, could also be red, but its never the blue)
3) Most RGB displays, while they have gradations finer than the eye can distinguish, cannot show the full spectrum in width (from 400nm to 700nm wavelengths). You can put as many bits as you want on to any consumer display, there are colours it simply cannot do.
4) Humans vary in their ability to see colour, making alot of the finer gradations imprecise. 8% of males have altered colour vision - as do a small percentage of women and those bits are really wasted on them. On the other hand, if you have had cataract surgery, the implantable lens will let in low end ultraviolet (which your retina can see) that our natural lens does not allow through. Not that I'm suggesting that it is good to see into the UV range
My 2c worth
Michael
There is no cryptographic solution to the problem where the intended receiver and the attacker are the same entity.
APNG files _are_ PNG files. We didn't create a whole new format (since that would be silly) so APNG files will still be .PNG files. The first frame in an APNG file looks to current PNG decoders to just be a regular PNG. The APNG spec specifies some additional chunks that if found tell an APNG aware decoder how to find the rest of the frames.
Experiment #1: 1x1 white pixel. Results: GIF 35 bytes; PNG 67 bytes.
Experiment #2: typical Slashdot icon resized to 16x16. Results: GIF 282 bytes; PNG 277 bytes.
I don't see the header size making a huge difference. What does make a moderate difference is that PNG is not bound to 256 colours. You can use a 16-colour palette, in which case pixels are packed in 4 bits each. You can use a 4-colour palette, in which case pixels are packed in 2 bits each. Pixels can be of many different depths between 1 bit and 48 bits. GIF does not have this flexibility.
This is important because icons very rarely use more than 16 colours. PNG gives a win in these cases.