The consumer electronics industry has yet to define a formal DVD standard to address the handling of high-definition-quality video programming. The DVD players available today are all designed to decode standard-definition-quality pictures using an MPEG-2 Main Profile @ Main Level video decoder device.

Thomson and DiVX hope to kick start the high-definition DVD market by offering two key technology components: a secure interface between a DVD player and HDTV receiver; and a smart card decrypter.

The companies' goal is to give movie studios an opportunity to offer their movies in the high-definition DVD format. By proposing a new strongly encrypted interface, the companies hope to minimize Hollywood's concern over distributing such high-quality images in an environment with less than perfect security.

In the joint development of the HD-DVD, Divx provided cryptographic technology while Thomson offered system expertise in DVD players and HDTV receivers, said Lauren Christopher, general manager of core product technology, multimedia and services R&D at Thomson Consumer Electronics.

The companies first encoded HD programming using HDTV Model Station's real-time encoder at an average rate of 10 megabits per second. The dual-layer 9-gigabyte DVD disk holds 133 minutes of images in 1,920 x 1,080i resolution, according to Christopher. The signals recorded in the proposed HD-DVD disk are not only encoded via MPEG-2 Main Profile @ High Level, but are also modulated by the U.S. HDTV's 8VSB modulation scheme. Further, strong proprietary encryption technologies are applied to the recorded signals on top of the HD signals.

The HD signals mastered on HD-DVD disks won't be demodulated, de-encrypted or decoded in a new DVD player. Instead, by connecting the DVD player and a HDTV receiver via RF cable, the encrypted 8VSB modulated signals will traverse from the DVD player to the HD receiver. From the HDTV receiver, the HD signals coming off the DVD player looks just like those transmitted from an HDTV channel.

The smart card inside the HDTV receiver will decrypt the incoming signal, while the HD receiver also takes care of VSB demodulation and HD decoding.

The proposed HD-DVD platform gives Thomson a chance to promote one of its pet causes — a non-IEEE 1394 interface between digital consumer devices.

The encryption technology devised in the new HD-DVD scheme is "a blend of Divx' cryptography and XCA," according to Thomson's Christopher. XCA is a smart-card based copy-protection system promoted by Thomson and Zenith for digital home networks. The XCA scheme competes against another copy-protection method called the Digital Transmission Content Protection (DTCP) for the 1394 interface. DTCP is informally known as "5C" because it was developed by five companies: Hitachi, Intel, Matsushita, Sony and Toshiba.

Jim Meyer, executive vice president of Thomson Consumer Electronics, said this week that "Thomson will not support 5C." Meyer said 5C is "a wrong approach for consumer products" because it requires service calls to upgrade the encryption scheme once it is broken.