Online Images That Stay True to Form on Any Screen

New York Times Technology
The New York Times

October 4, 2001

WHAT'S NEXT

Online Images That Stay True to Form on Any Screen

By JEFFREY SELINGO

EXPLORING the Web on a cellphone may seem like a good idea when you're
constantly on the run, but with sites bursting with graphic images, it's
certainly not very easy. You're likely to find yourself staring, say, at a
part of a giant logo unless you can find special scaled-down versions of Web

sites that many developers have created for wireless users.

Now help is on the way. Last month the World Wide Web Consortium, which
promotes Internet standards, recommended a graphic technology that is
designed
to make many Web images fit any screen, including the tiny displays on
wireless phones. Known as Scalable Vector Graphics, or SVG, and developed
with
contributions from leading software and hardware companies like Adobe, Corel
(
news/quote), Apple and Microsoft ( news/quote), the format is text-based.
This
allows the graphics to load faster and enables search engines and screen
readers to locate printed matter in images.

Most of the graphics on the Web today are created as bitmaps, collections of

tiny pixels plotted precisely on a grid that when sent to your computer
generate a whole image. When resized to fit a monitor's screen, however,
bitmap images lose much of their original composition. If bitmap graphics
are
stretched, for instance, the user can actually see each of the pixels that
compose the picture.

Vector graphics, on the other hand, draw images based on mathematical
descriptions of the length and position of every line and the tone of every
color. Those descriptions, for example, may include commands to draw a
circle
of a certain diameter filled with a specific gradient of red. When an SVG
image is resized by a Web browser to fit a particular screen, it redraws the

graphic based on the same data, scaled up or down as needed.

"People are accessing the Web with a wider range of devices that all want a
different-size display," said Chris Lilley, chairman of the SVG working
group
of the World Wide Web Consortium. "But users don't want to have to go to a
special version of the site for hand-helds. They want to go to the same site

as everyone else."

Bitmap images - in the form of files with extensions like .bmp, .jpeg and
.gif
- are not going away anytime soon, since photographs on the Web will still
require the format. But for other kinds of images, vector graphics may
become
the format of choice.

Because vector graphics are text descriptions, they are compact, unlike the
bulky bitmap images, which tend to crawl through dial-up Internet
connections.
SVG images offer another advantage for Web users because they are more
interactive. People using road maps from the Web, for instance, are often
hampered by their limited viewpoints: one view may provide a jumble of
detail
from a distance, while the next available one homes in too closely for the
user to orient himself. With a map created with SVG, you can zoom in or out
to
the extent you want without waiting for a new image to load each time, much
as
if you were using the magnifying glass in Portable Document Format files.

"SVG is powerful," Mr. Lilley said. "You can manipulate the data in a
graphic
and it displays immediately. There's no more lag time while it goes back to
the server to get a new image."

Another benefit of SVG is that the user can search for text in graphics.
Search engines and the Find function in Web browsers tend to miss words or
numbers in graphics because they are broken up into pixels in a bitmap
image.
But in SVG graphics, the text and the mathematical information are separate
from each other, allowing search engines to spot printed material. That will

be especially helpful to blind people who depend on screen readers to use
the
Web.

"SVG will help Web designers who are working to comply with strict standards

for accessibility," said David J. Emberton, a co-author of two books on
Flash,
another popular vector-graphic Web technology. "Disability advocates have
been
pushing for more access to graphics, but until now the technology really
wasn't there."

Since the new technology was only recently approved, few Web sites offer SVG

images. Users of the Netscape Navigator or Microsoft Internet Explorer Web
browsers may need to download a free plug-in from Adobe
(www.adobe.com/svg/viewer /install/main.html) to view the images but should
first check to see whether they already have it, since the plug-in was
included with Acrobat Reader 5.0. (A list of sites that already use SVG
images
can also be reached via that page on the Adobe site by clicking on
Community.)

The need for a plug-in may at first limit the spread of the technology. "I
don't see SVG having widespread use until it's integrated into the browser,"

Mr. Emberton said.

Steve Snell, a senior marketing manager at Adobe, said that the company
would
prefer that SVG technology be included in browsers but that it was "an issue

beyond our control." He predicted that designers and consumers would
eventually pressure browser manufacturers to include the technology in their

coming versions.

Future versions of the Adobe plug-in will allow users to print SVG images
with
the same quality as those in a PDF document, Mr. Snell said.

"SVG is going to be embraced as people realize its strengths," he said.
"Obviously, if the larger sites adopt it, people will be curious."


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