Consortium backs mobile interface for high def video

SAN JOSE, Calif. — Nokia, Samsung Electronics, Silicon Image, Inc., Sony and Toshiba Corp. have formed the MHL Consortium. The group has created a draft specification for the Mobile High-Definition Link originally announced by Silicon Image in 2008 for sharing high-definition video between mobile devices and televisions.

Details of the spec are available only as a $100 download from the group's Web site to anyone willing to sign a confidentiality agreement. The group plans to release before July a final spec along with costs of adopting it and procedures for testing compliance.

"We never actually shipped any product based on the original MHL technology, but we used the announcement to recruit partners for the consortium," said Tim Vehling, vice president of Silicon Image's products group. "We did have chips, but they never shipped for any meaningful revenue," he said.

The Silicon Image technology described in 2008 sounds identical to the high-level description of the consortium's current draft spec. Both support transfers of uncompressed 1080-progressive video using a five-pin connector. Both support High-bandwidth Digital Content Protection as well as power to the mobile device over the connector.

Both Vehling and Barry McAuliffe--a Silicon Image business development manager named president of the new consortium--said the five members of the group all contributed to the new spec. However, they declined to state whether or how the spec is different from the original technology.

Anyone wishing to use the technology will need to pay the consortium a fee and royalties that will be defined in a future adopter's agreement. That agreement and details about compliance testing should be released when the spec is complete later this year.

"This is Silicon Image's attempt to make itself relevant in the mobile phone market," said Brian O'Rourke, principal analyst at InStat LLC.

Alternatives to MHL are few. Less than 0.1 percent of all handsets will use the mini C High Definition Multimedia Interface (HDMI) connector this year, said O'Rourke.

Silicon Image helped develop the HDMI interface now widely used to link HDTVs and set-top boxes. It licenses the technology through its HDMI Licensing LLC group.

"The HDMI port is big, while MHL works over a USB link which is becoming fairly prevalent in phones," O'Rourke said.

Wi-Fi, increasingly used in handsets and TVs, lacks the quality of service to handle high definition video, O'Rourke said. However, he has not yet decided whether to forecast sales for MHL.

Silicon Image sampled its first MHL chips in February 2008. It said the link supported data transfers at rates up to 2.25 Gbit/s, consuming 60 mW average. The approach pared down the three Transition Minimized Differential Signaling channels in a standard HDMI connection to just one running over any connector that provides at least five pins.

In July 2008, Silicon Image rolled out a follow up chip supporting both MHL and HDMI. At that time, a representative of Analog Devices Inc. said the new interface could confuse a mobile market beginning to adopt HDMI over a mini C connector.