In the last year and a half, a broad alliance of high-tech companies and Hollywood studios has been trying to address this problem through an organization called the Digital Entertainment Content Ecosystem, or DECE. Five of the six major Hollywood studios (Warner Brothers, NBC Universal, Sony, Paramount and Fox, but not Walt Disney) are involved, with Microsoft, Cisco Systems, Comcast, Intel and Best Buy.

The group is setting out to create a common digital standard that would let consumers buy or rent a digital video once and then play it on any device. It might sound technical, but it could be crucial to persuading consumers to buy all the splashy new Internet-connected gear that tech companies will demonstrate at C.E.S., like HDTVs and set-top boxes that can download TV shows and films.

Under the proposed system, proof of digital purchases would be stored online in a so-called rights locker, and consumers would be permitted to play the movies they bought or rented on any DECE-compatible device.

So, for example, business travelers might find that their hotel room television could tap into their personal movie collections. Consumers could buy Blu-ray discs and have digital copies of those films accessible from all of their devices, even their mobile phones. And a PC maker could customize a new laptop for buyers by loading it with all their movies and shows  and eventually even their video games and e-books.

These advances may not be all that far off. On Monday, the digital content organization plans to announce several moves that signal it is ready for companies to start building devices and services with the technology this year. Industry observers expected such an announcement last year.