Consortium supports HD video mobile interface

Nokia, Samsung Electronics, Silicon Image Inc., Sony and Toshiba Corp. have formed the MHL Consortium and 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 TV.

Although details are scarce, it appears a battle is brewing between the group's MHL spec and low-power versions of HDMI. At stake is how millions of high-end mobile devices will get video to and from TVs and set-top boxes.

Details of the new MHL spec are available only as a $100 download from the group's Website 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, VP 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 and a version of the HDMI interface.

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

Both the new MHL draft spec and Silicon Image's 2008 products support High-bandwidth Digital Content Protection. And both 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.

Mobile HDMI
Engineers at Analog Devices Inc. said they have looked at the spec and found little that is new beyond the functions of the original Silicon Image chips. ADI sells low power chips for HDMI which includes support for a new D connector geared for mobile systems, defined as part of the release of HDMI 1.4 about six months ago.