[Bug 18574] restore support for MNG and JNG

Alien42 · Post by **Alien42** » March 17th, 2007, 8:28 am

But it's loopable like GIF though, yes?

Old GlennRP · Post by **Old GlennRP** » March 17th, 2007, 9:22 am

Sure. The draft spec isnt done yet but before it's done it will have an "iterations" parameter. It won't have any internal loops like MNG, but the entire animation can be repeated like AGIF and APNG. The playlist can reuse any number of tiles as backgrounds or like sprites.

BenoitRen · Post by **BenoitRen** » March 17th, 2007, 12:09 pm

Because at the moment all we have [in general useage] is GIF, which can only do 256 colours.

Of course. But we already have MNG, so I don't see why they need to waste time making another animated PNG format.

Alien42 · Post by **Alien42** » March 17th, 2007, 12:38 pm

GlennRP wrote:Sure. The draft spec isnt done yet but before it's done it will have an "iterations" parameter. It won't have any internal loops like MNG, but the entire animation can be repeated like AGIF and APNG. The playlist can reuse any number of tiles as backgrounds or like sprites.

So perhaps in whatever graphics editing prog, setting iterations to 1 or higher would make it repeat that many times, whereas 0 would signify playing through the animation indefinitely?

BenoitRen wrote:Of course. But we already have MNG, so I don't see why they need to waste time making another animated PNG format.

A valid point, but at the end of the day unless someone who has the necessary programming knowledge either creates an extension/plugin or actually modifies & compiles the Moz/SM/Ff/Tb source code & then makes it available to everyone else, then we have to put up with whatever the Mozilla developers give us. If they don't want MNG then apart from the above alternative there's nothing we can do.

The way I see it is this, mPNG might not be what we'd prefer, but it's better than nothing.

Old GlennRP · Post by **Old GlennRP** » March 17th, 2007, 3:15 pm

Alien42 wrote:So perhaps in whatever graphics editing prog, setting iterations to 1 or higher would make it repeat that many times, whereas 0 would signify playing through the animation indefinitely?

It would make it *play* that many times, including the first time around. And yes, 0 would mean
forever. This feature is the same in the proposed APNG and mPNG as well as available in MNG.

Alien42 · Post by **Alien42** » March 17th, 2007, 3:20 pm

I don't suppose there's an ETA for this new feature?

Old GlennRP · Post by **Old GlennRP** » March 17th, 2007, 3:25 pm

Whoops, it isn't exactly the same in MNG. [digs out 6-year-old MNG spec] MNG uses 0x7fffffff for forever and 0 and 1 both mean don't iterate after the first time through the animation. In internal loops (using the LOOP/ENDL chunks), 0 means skip the loop, 1 means run the loop once, and 0x7fffffff means loop forever.

Old GlennRP · Post by **Old GlennRP** » March 17th, 2007, 3:28 pm

Alien42 wrote:I don't suppose there's an ETA for this new feature?

Give us a break. The mPNG concept was only proposed yesterday afternoon. Figure at least four weeks, maybe a little more to let the dust settle on APNG.

Alien42 · Post by **Alien42** » March 17th, 2007, 3:47 pm

GlennRP wrote:Whoops, it isn't exactly the same in MNG. [digs out 6-year-old MNG spec] MNG uses 0xffffffff for forever and 0 and 1 both mean don't iterate after the first time through the animation. In internal loops (using the
LOOP/ENDL chunks), 0 means skip the loop, 1 means run the loop once, and 0xffffffff means loop
forever.

LOL, way over my head dude, I just meant if it would seem similar/the same to the end users as the current method [for aGIFs].

GlennRP wrote:Give us a break. The mPNG concept was only proposed yesterday afternoon. Figure at least four weeks, maybe a little more to let the dust settle on APNG.

4 weeks?

Seriously though, that's cool. I was just worried it would be months, or an even vaguer "eventually", & then in the mean time someone would suggest some other format & the whole thing would just go on & on, with no hope of the feature ever actually making it into a stable, released version.

Old GlennRP · Post by **Old GlennRP** » March 17th, 2007, 4:12 pm

Alien42 wrote:
GlennRP wrote:Give us a break. The mPNG concept was only proposed yesterday afternoon. Figure at least four weeks, maybe a little more to let the dust settle on APNG.

4 weeks?

Maybe a little more. A few days to finalize and document the proposal, then 2 weeks of formal discussion, then 2 weeks of voting. Confusing the issue is that APNG and mPNG are both in the mix, and we have conflicting requests from the APNG proponents to slow down and speed up. Also confusing is that the discussion is split between the PNG group mailing list and the APNG spec bug on bugzilla. The PNG group is eight days into the formal discussion period for APNG.

Alien42 · Post by **Alien42** » March 17th, 2007, 4:44 pm

How about if we stick them all in a room & whoever comes out alive is the winner?

I do have 1 suggestion that perhaps you could add in to the mix [unless it's already in there], & that is that whatever we end up with, that it still have a .PNG extension [rather than .APNG, or .mPNG]. The reason for that would be that in my limited understanding of the issue it ought to mean that as soon as the applications [Firefox, Thunderbird, etc] were ready to display the files, & the files are actually created, then they could start being used. I'm thinking specifically of useage on forums - it's been said that the various animated versions of PNG would still display for non-animated capable software as a still image, so people could start "pimping" Firefox's new ability all over the place.

Old GlennRP · Post by **Old GlennRP** » March 17th, 2007, 6:53 pm

Alien42 wrote:How about if we stick them all in a room & whoever comes out alive is the winner? :D

That's just about what is happening.

Alien42 wrote:I do have 1 suggestion that perhaps you could add in to the mix [unless it's already in there], & that is that whatever we end up with, that it still have a .PNG extension [rather than .APNG, or .mPNG].

That's already there. There was a big squabble about that but we have evidently settled on: the files will have the .png file extension and the MIME type will be video/x-png. This still has to pass the voting though.

Alien42 · Post by **Alien42** » March 17th, 2007, 8:11 pm

GlennRP wrote:That's already there. There was a big squabble about that but we have evidently settled on: the files will have the .png file extension and the MIME type will be video/x-png. This still has to pass the voting though.

Why would anyone argue against it? Do they actually enjoy making things more complicated than they need to be?

Old GlennRP · Post by **Old GlennRP** » March 18th, 2007, 3:28 am

Alien42 wrote:Why would anyone argue against it?

The solution has to comply with the PNG spec that says the png datastream contains a still image, and with the RFC that says "image/something" contains a still image. Some people say that "image/gif" which violates the RFC when the gif is an ani-gif, is ample precedent for us to violate it as well.

Old GlennRP · Post by **Old GlennRP** » March 18th, 2007, 3:35 am

Alien42 wrote:
GlennRP wrote:Whoops, it isn't exactly the same in MNG. [digs out 6-year-old MNG spec] MNG uses 0x7fffffff for forever...

LOL, way over my head dude

FYI, 0x7ffffff is C notation for the largest possible signed 32-bit number. And yes, mPNG and APNG are like aniGIF in their handling of iterations.