Newsgroup: it.comp.www.html
Titolo: PNG e NETSCAPE

Il formato grafico PNG è senz'altro migliore del JPG e del GIF, per le
dimensioni del file, la qualità, la profondità e le trasparenze. Gli manca
solo l'animazione, ho sentito che stanno elabornado un nuovo formato per PNG
animate, sapete quanto tempo dovremo ancora aspettare?
Su Netscape ci vuole un Plug-In per visualizzare le PNG, ma per tutte le
versioni o le più recenti l'hanno integrato?

dimensioni del file,
[CUT]
Come hai fatto??? Tutti i miei tentativi hanno portato a file di dimensioni
maggiori a pari qualità.
Mike

>dimensioni del file,
___________
First I would like to thank everyone who took the time to reply to my
questions. Now on to the results.
Introduction:
As expected, the answer to whether anyone is using PNGs for web design
was a unanimous...NO!
I had thirty-six people reply and almost all of them stated that they
DO
NOT use PNGs in web site design. (There are some usage's of PNGs, but
I
will discuss them later.)  In addition, most people stated that they
had
no plans to start using them anytime soon. There were many reasons
given
for why web designers are not using them.
The main reason is due to the belief (whether accurate or not), that
there are still too few web surfers who are using PNG capable
browsers.
As web designers, we generally agree that there are three main goals
in
designing and using graphics in designing sites:
1. Fastest load time with the best appearance quality possible.
2. Viewable without surfers needing to install any type of plug-in.
3. Consistent appearance across all platforms and browser versions.
PNG Facts: (brief overview)
PNGs behave like a hybrid of GIF and JPEG files. They allow
transparency
like GIFs; "lossless" compression like GIFs and millions of color like
JPEG. PNGs are closer to GIFs rather than JPEGs so they are more
likely
to be used in place of GIFs. So I will compare PNGs with GIFs.
PNGs vs. GIFs:
- PNGs are superior to GIF files due to their ability to display
millions of colors rather than GIFs limited 256. It also allows
variable
transparency using alpha channels. PNGs also offer Gamma Correction
which allow you to control image brightness across all platforms.
- GIFs are better because they support multiple frames (i.e. animated
GIFs) and the files tend to be smaller than PNGs. (This is expected
due
to the larger amount of data that PNGs retain.)
PNG supported Browsers:
PNGs have been supported in the big three browsers (Netscape, IE and
AOL) since version 4.x. Unfortunately, a huge number of people are
still
using older browsers. Many people replied to me with statistics
showing
that approximately 20-30% of web surfers are still using non-PNG
"friendly" browsers. It was also expressed to me that, until this
number
lowers to around 5-10% they will not start to use PNGs.
In my introduction I alluded to the fact that some people may be
basing
their reluctance to use PNGs on erroneous statistics. This is because
there is at least ONE very common plug-in which adds PNG functionality
to web browsers. Apple's QuickTime 4 plug-in supports PNG. (Version 3
may have supported it too.) Quicktime, although not installed in every
browser is in a large percentage of them, so the 20-30% of surfers who
are currently still using a v2.x or v3.x browser could have PNG
ability
through QuickTime. This is something that should be thought about when
looking at this purely from a statistical view.
What can we do:
We are in a catch-22. On one hand, we need to find a way to encourage
migration to PNG supported browsers by using PNGs, but we also want to
present our sites so that everyone can see them. On the other hand,
without a "need" to, surfers have no incentive to upgrade. As web
designers we only have control of the first of these two. We need to
consider taking a proactive stand here and make some decisions that
may
not be popular in the short run, but could be beneficial to
everyone--web designers, our clients and web surfers--in the long run.
[Apple computer has done this three times: First they went to the
smaller floppy then they moved to USB (and FireWire) and most recently
they completely removed the floppy drive from their computers
completely. Each time they received criticism, but in the end they
were
praised from taking such a bold move.]
There are things that we can do while keeping problems to a minimum.
One
of the best options would be to use javascript to determine to the
surfers browser capabilities and then write alternate code for
displaying either a GIF or PNG image. There was a recent article by
Paul
Anderson about how to do this on C|Net's Builder.com.
(
http://www.builder.com/Authoring/Tagmania/101199/
)
Other Usage's for PNGs:
As I mentioned above, people are using PNG files. The four main uses
that I came across was as a storage format, for off-line uses, on
Intranets and embedded in Flash files.
PNGs for storage:
Most of the major graphic design applications support PNG as a save
option. The benefits of keeping the original in PNG format is that you
don't have degeneration like you do when you resave JPEG files. In
addition, due to so many applications supporting it, it is a very
handy
format for moving files between applications.
Off-line Usage:
One person who replied mentioned that he used the PNG format for
saving
graphic design artwork he made for CD.
Intranets:
PNGs can also be used in Intranet situations where the browser CAN be
dictated (e.g. company MIS).
Flash:
One of the best uses for PNG, at this time, is as embedded objects in
Flash files. Flash has supported PNG files since version 3. Once
embedded into a Flash (.swf) file, browsers equipped with the Flash
plug-in can view the PNG as a part of the Flash file.
Future of PNG:
There appears to be two new graphic formats on the horizon which will
either expedite the move to using browsers that support PNGs or which
will make PNGs obsolete before their time.
These two new formats are MNG (animated PNG files)
(
http://www.cdrom.com/pub/mng/
) and JPEG 2000
(
http://www.jpeg.org/public/jpeglinks.htm
).
Conclusion:
I started this poll because I have read and heard about PNGs for a
while, but I had not come across many in use. I wanted to see how
prevalent their usage was before I started to use them myself. (Yes,
it
is true, I have not used them yet either!) I learned how reluctant
people are to use them due to either a lack of understanding/knowledge
(of the PNG format) or for concern of "end users" not being able to
view
them. I came across a lot of information that I wanted to share with
you
about PNGs. Here are some links:
The PNG Home Site:
http://www.cdrom.com/pub/png/
An Example: (Thanks to: Mark Christol)
http://home.fuse.net/christol/Ugrrl.html
A Book for further research:
http://www.amazon.com/exec/obidos/ASIN/1565925424/o/qid=939828609/sr=8-1/00
Definition of PNG:
http://whatis.com/png.htm
PNG supported Image Editors:
http://www.cdrom.com/pub/png/pngaped.html
PNG supported Browsers:
http://www.cdrom.com/pub/png/pngapbr.html
Latest breaking PNG news:
http://www.cdrom.com/pub/png/pngnews.html
Final Thought:
I hope some of this information is helpful to others. I know I have
learned quite a bit from my research. Thanks again for everyone who
helped with my survey.
--
Dr. Jim Butler, CEO & President
Scuba Web Design
_____________________________________
Andrea Toniolo
________________________________________
Freelance WebDesigner,Writer,Consulting
________________________________________
   E-mail: 
and...@andreatoniolo.com
 
Http://www.AndreaToniolo.com
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________________________________________
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