Portable media players capable of playing video need a major success story before the market will take off, and Apple could be that supplier, according to market research firm Instat.

In a new study the firm projected sales of portable media players to reach 7.5 million units worldwide by 2009, up from this year's 1.2 million.

The figure includes the Zen Vision and Zen Portable Media Center, both from Creative, but excludes sales for Sony's PSP. Although the PSP device plays movies stored on the special Universal Media Disk, it is primarily marketed as a gaming device.

Stephanie Guza, an analyst at Instat, told vnunet.com that video playing digital media devices remain limited to a niche market of early adopters. These include commuters using public transport, frequent air travellers and parents that use the device to keep their children quiet.

In addition to a limited awareness with consumers, current prices of around $400 prevent them from becoming mainstream.

Instat believes that these issues could be solved by Apple. The company is said to be working on a video enabled version of its iPod music player, and some industry analysts predict a release by next year.

"It takes a big vendor to build awareness. That could be a company like Apple," said Guza.

But the analyst warned that, while an increase in volume would help to lower prices, they are likely to stay at a high level.

"It will be a few years before we'll see price points becoming lower for the general consumer," she explained.