Switched On: WHDI seeks to unplug hi-def

Each week Ross Rubin contributes Switched On, a column about technology, multimedia, and digital entertainment.

The past few years have seen a wide range of wireless technologies proposed to substitute for the now nearly ubiquitous (at least in terms of new HDTVs) HDMI connectors, but the dust is just starting to settle. Some proposals involve squeezing more juice out of 802.11n. Others rely on ultrawideband technology. Yet another that has many in the industry excited is from SiBeam, which intends to use the 60GHz band to deliver uncompressed 1080p video at 4Gbps. That technology, embraced by a group called WirelessHD, had received the most public support among major consumer electronics companies, with Panasonic, Sony, Samsung, Toshiba and LG listed on its site as promoters (and others listed as adopters).

But WirelessHD is still a ways from consumer availability and recently another wireless high-definition technology has attracted some heavy hitters of its own, including Sony, Samsung, Sharp and the cable set-top division of Motorola. Amimon's WHDI (Wireless Home Digital Interface) is different from many of its emerging competitors because it is designed, like WiFi, to be a technology that blankets the home, whereas most competitors focus on an in-room solution. WHDI even operates in the 5GHz band (like 802.11a and 802.11n), but sheds the costly bandwidth overhead WiFi utilizes to correct transmission errors. In contrast, WHDI is a "video modem" technology that attaches to a device's video output to send uncompressed 1080p video. After that, it's survival of the fittest for the bits.

While WHDI does not compress the bits in the video, it does not treat them all equally. The technology looks for what are the least significant bits, say, in a dark gray pixel next to a darker gray pixel in the background of a scene, and assigns them a lower priority than, say, a bright yellow pixel next to a black pixel in a race car moving across the screen. As a result, any degradation caused by wireless interference is minimized, and Amimon claims it is almost impossible to notice. Still, the potential for deterioration could discourage videophiles with the kind of disposable income and complex home theater setups that would be a natural early target market.

Consumers will be able to get their hands on Amimon's technology later this year as it is the basis of Belkin's FlyWire, a product designed to transmit video wirelessly using a transmitter that can accommodate a number of video sources and a relatively small receiver. The FlyWire will likely cost more than some HDTVs on the market, and unfortunately it will not be compatible with the forthcoming WHDI spec. Amimon says that's alright because FlyWire is more of a point solution for people who are willing now to invest in reliable high definition video.

Beyond the earliest adopters, there seem to be two main potential consumer applications for WHDI. One in which it looks particularly strong is creating a better bridge between the PC and television, and might prove to be a much better solution for a digital media adapter such as Apple TV or a Media Center Extender. Amimon claims a lengthy list of commands that can be signaled remotely to the original playback device that might be in another room, and that it is in active discussions with several PC-related companies. However, demand for this functionality is still relatively low, and only partly because the connections aren't fast enough. Multi-room DVR could be another opportunity, but relatively few TV service providers offer it today.

A larger but more competitive market is connecting AV components within a room while minimizing cable runs. Down the road, the vision is that the television would need to be fed only power through the wall, and DVRs, Blu-ray players, and game consoles would all transmit video to it wirelessly. Amimon is hopeful that, at some point, companies will be able to offer its technology for the same price as (and perhaps alongside) WiFi, and consumers will get it "for free." However, it will take time for prices to come down to the point where consumer electronics companies can integrate it inside their products so, at least for the next year, the heavy lifting of high-definition video will continue to be done with HDMI cables.

Ross Rubin is director of industry analysis for consumer technology at market research and analysis firm The NPD Group. Views expressed in Switched On are his own.