SAN FRANCISCO--Adobe Systems, retooling as fast as it can for a future of Web publishing and Web apps, sees the technology as mostly caught up to the Flash technology that Adobe previously preferred.

"I think it's close to 80 percent," Arno Gourdol, Adobe's senior director of Web platform and authoring, said in an interview during the Google I/O show here.

Gourdol, who leads Adobe work to embrace Web standards, has a lot on the line as the company tries to make a difficult transition away from the widely used but fading Flash. He's eager to convince skeptics that the company is serious about it: "We're not just looking at parity with Flash. We're trying to go beyond what you can do with Flash."

The company for years advocated its Flash Player plug-in as a way to deliver games, video, and slick, magazine-style layouts to Web browsers. But at the same time Adobe was struggling to bring Flash to the new world of mobile devices -- including a particularly public fight when Apple barred the plug-in from iOS -- the company started branching out to Web standards, too.

With new Web design and programming products such as Muse and Edge, and with an active effort to design new standards, Adobe is fully engaged in the post-Flash world now. Emblematic of the seriousness of the effort: two Adobe employees were the only non-Google people to make presentations at Google I/O show, where Web technology is a major theme.

Some of Adobe's suggestions are making their way to the Web already, with browser makers on board. But there are problems in other areas -- hardware-accelerated 3D graphics and support for high-resolution displays such as the Retina screens of the third-generation iPad and new top-end MacBook Pro.

The Retina problem

The display issue stems from a years-old struggle to deal with the pesky problem of pixels. In the early years of graphic user interfaces, pixels were relatively fixed in size -- 72 of them per inch on Macs and 96 pixels per inch on Windows. That let people create things like toolbar icons and Web page graphics that would show up at a predictable size on a screen.

The problems have been getting worse in recent years, though, first with some higher-resolution laptops and mobile phones. It became particularly acute with the Retina displays on the 2011 iPhone 4S and the 2012 iPad and MacBook Pro. Those double the linear resolution of their predecessors' screens, which means quadruple the number of pixels -- 2,880x1,800 in the case of the new MacBook Pro compared with 1,440x900 for its predecessor.

Images shown at the higher resolution look great, but they're also four times bigger files -- and Web browsers don't know how to fetch them properly. Most graphics on the Web on a MacBook Pro today don't take advantage of the higher-resolution displays at all. Web developers still don't have a standard way to know what size graphic they should send to a Web browser, though it can be done -- for example visiting Apple.com with the Retina-optimized Safari.

Those who are curious about the proposals so far can check Bruce Lawson's discussion and the sometimes emotional debates. Adobe, which knows a thing or two about images, isn't yet satisfied.

"The reality is it is a fairly difficult problem," Gourdol said. "We don't think anybody has proposed the best way yet."

And it's not just a matter of image quality. "There are bandwidth limitations," he said, because higher-resolution images take longer to download and display. "You'll want more control of Web pages, not just PPI [pixels per inch] but bandwidth."

Scalable Vector Graphics (SVG) can help in some cases by replacing bitmap graphics, made of a grid of pixels, with vector graphics, made of mathematically constructed geometric shapes. As the name suggests, SVG graphics can be scaled to different sizes, but they aren't suited to imagery such as photographs. And even when SVG is appropriate, most notably with stylized graphics such as icons and logos, those graphics should be adapted for different physical display sizes -- on high-resolution Android devices as well as on Apple Retina products.

Gourdol sees SVG as useful and easing multi-resolution difficulties, but it's no panacea.

"Creating two versions [of a graphic] is way better than creating five," he said. "Vector graphics work for some things, but you still need bitmaps. What you want is a combination of vector graphics and multi-resolution bitmaps. It's going to require a lot more work."

WebGL and 3D graphics

Another issue that must be resolved is WebGL, a low-level interface for 3D graphics adapted to programs such as video games and virtual worlds. Mozilla, Google, and Opera are supporters, and Goudol said Apple is "very involved," too, but Microsoft has strongly criticized WebGL as a security risk because of worries about downloaded software called shaders running on the graphics processor.

Gourdol is trying to coax Microsoft into the fold. "I'm optimistic" Microsoft will eventually come around, he said. WebGL enables "a very expressive Web and high-quality games."

He thinks there might be help in some work Adobe has done on a Web proposal of its own -- CSS shaders and filters for programmable, hardware-accelerated graphics effects through the Cascading Style Sheets a technology for formatting and effects on the Web.

Discussions about the avoiding security problems for CSS shaders led to a "great solution -- hiding data so there's no way malicious shader code can get access to it," Gourdol said. (One security risk is that a malicious shader software could get information elsewhere on a Web page, a problem akin to cross-site scripting problems on the Web.)

"CSS shaders are a smaller problem," a subset of the WebGL issue, Gourdol said, but thinks it could help point the way to a solution.

Adobe has built prototype implementations of CSS shaders and filters for both WebKit, the open-source browser engine within Safari and Chrome, and for Gecko, the engine within Firefox.

Next up: Blend modes and DRM

Drawing again on its Flash experience, Adobe also has proposed "blend modes" for Web graphics. Offered for years in Photoshop and Illustrator, Blend modes offer a variety of ways of overlaying one graphic on another, bringing more options than just one graphic completely occluding another.

One example Adobe particularly likes is making an image show within the boundaries of letters. A travel agent's brochure with the word "Peru" in large letters could have photos in each letter.

Gourdol is optimistic it'll be easy to build into the Web.

"It's one of those things that should be on the Web. I think it'll get into browsers pretty quickly," he said. "It's small and self-contained."

More controversial is copy protection for video, a major feature that Flash video offers but that Web video does not. HTML standard editor and Google employee Ian Hickson has strongly derided digital rights management, which restricts people's ability to copy video, in Web standards.

"It's supported by Google but not Ian Hickson," Gourdol said, and Adobe and Netflix are also working with Google on the technology.

"The content providers think it's pretty important, and we want to give them solutions, particularly for the high-definition content," Gourdol said.

Even though premium video is one of the major sales pitches for Flash today, along with games, Adobe isn't trying to reserve that feature just for Flash, Gourdol said.

"We're not trying to not do the right thing," he said -- in other words, not trying to protect Flash by keeping its feature off the Web. "We're working with everybody to make it happen."