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PNG Second Edition Is a W3C Proposed Recommendation
Quadraphonic writes "I'm surprised I haven't seen this yet: PNG Second Edition is a W3C Proposed Recommendation. Thoughts?"
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I use a lot of PNGs with client's websites.
The proplem is the non-existant Alpha support on MSIE. Every other [modern] browser reads the alpha beautifully.
For creating PNGs, outside of using GD in PHP, I use Fireworks which so far does the trick as long as you use the Export Preview function, not the native 'save as..' function. WAY better than GIFs by far!
Personally, you have to individual check on each image that comes into your browser to know who's using what. PNG is used more than you think. But I still wish MSIE would wise up to the alpha problem.
AnamanFan - Trying to find the Truth, one post at a time.
Maybe some of you could take the time to sign a petition to help get (proper) PNG support in MSIE?
Is PNGOUT by Ken Silverman. It's even beats PNG Crush most of the time. I create my PNG's in Photoshop, and then when I use PNGOUT before going live.
Google doesn't index user sigs, so stop trying to "Google Bomb" with them.
Your reality is lies and balderdash and I'm delighted to say that I have no grasp of it whatsoever. - Baron Munchausen
Oh, there's another problem - lack of a good program to save PNGs. AFAIK, Gimp is the best PNG generator around all the Windows photo editing software I used to use (Photoshop and Paint Shop Pro) generated terribly large PNGs, I used to save them as GIFs.
What's that mean? My site uses both photoshop and imagemagick to generate PNGs and they come out the same as gimp. An algorithm is an algorithm. I think that maybe gimp might default to PNG8 while photoshop defaults to PNG24. Either way its customizable. Photoshop has full PNG compatibility.
Photos.
And second - what is the CSS hack? That would be handy for people to do as an interm fix. (And real world html is all about interm hack fixes to get things to look right).
--
Evan
"$30 for the One True Ring. $10 each additional ring!" -- JRR "Bob" Tolkien
For photos, yes, but rarely for repetitive images with few colors (which most web graphics are).
You can actually display alpha layered PNGs on Microsoft Internet Explorer, starting from version 5.5, using an ugly workaround using DirectX and a CSS3 directive.
.htc file coming from here:
.htc source.
:)
Now, be prepared: it will work _only_ with tags, so no alpha for background images yet. Still, it's an improvement.
I still don't get why they didn't implement it properly in the first place, let's not talk about it, it's a 1996 recommendation and I'm already so mad and frustrated by their bogus workarounds covering their flaws (XML parser bugs, ignores the IGNORE directive in DTDs, anyone?)
Anyway, the trick is to use a CSS on all images:
img { behaviour: url('/path/to/.htc'); }
using the
Thanks
You just have to point to a 1x1 spacer GIF in the
Works pretty fine, is compatible with Opera/Mozilla/IE and _at last_ you can get rid of 1988-oriented GIFs.
Should you want to support IE 5.5, welcome to the future of the web of yesterday
No, the reason IE for Mac displays PNG alpha correctly is because it's a completely different browser, different rendering engine, different CSS support, the works. No one is entirely sure why this is, but it's pretty clear as most of IE-Windows' bugs don't happen in IE-Mac.
Mind you, IE-Mac has a whole *host* of problems all of it's own...
Random and weird software I've written.
If you want to recompress the bloated PNGs written by Photoshop, a guide to PNG optimization is available.
So, enhancements to the underlying OS are necessary for the features that most other modern browsers have, such as transparent PNGs, popup blocking, and tabbed browsing? Obviously, they have no intention of ever adding these features to IE. This is awful. It's staggering that AOL just snubbed the most innovative browser on the planet to make a deal to use a stagnant, obsolete 1998 browser until 2010 (Re: this story).
I think this is just considered an update from the PNG spec 1.0 to spec 1.2 (or, maybe 1.3). The PNG home site mentions version 1.1 (with color correction) & 1.2 (with international text). The text in the linked recommendation mentions that it's the same text as the ISO standard (except for "cover page and boilerplate differences"); the PNG news page mentions that the two announcements are related, but without mentioning why they're related. It mentions "errata and clarifications" from PNG spec 1.0.
Bleh. Anyway. It's not about PNG 2.0 or anything. If you want animation, you still have to use MNG.
This isn't PNG 2.0, it's PNG second edition: think of it as being like the difference between Win98 and Win98 second edition.
When the W3C release a "second edition" recommendation, it's mostly editorial changes - see the changes summary in the PNG recommendation (or see XML 1.0 second edition, which is the current XML spec, for an example of another "second edition").
The linked spec is basically compatible with the original version, but some of the conditions for conformance have been tightened up (not that that matters for IE purposes since it didn't conform anyway) and the necessary verbiage to use the text as an ISO standard has been added (W3C policy is to release "recommendations" which are treated like standards, but this one is actually going to be a standard in theory as well as in practice).
Even without fancy transparency features PNG is still very useful.
First, unlike GIF it supports more than 256 colors
Second, just like GIF it's lossless (It could be said that conversion to 256 colors is a loss though)
Third, it's a bit smaller than GIF
JPG can't deal properly with thin lines. Which means that if you want a good encoding of a picture that contains lines and text, like color comics you have to use JPG or GIF. If the comic happens to have many colors then PNG is the only thing that will look good.