HDMI and DVI

HDMI FAQ's

Home > Education Center > FAQ's > HDMI FAQ's

DVIGear is your source for information on the audiovisual industry's technologies. We have compiled our most frequently asked questions on HDMI, DVI, HDCP, and more. We will continue to add to and update this list, so check back often!

If you have any questions, comments, or suggestions, please feel free to contact us by email at: sales@dvigear.com or by phone at 770.421.6699.

What is HDMI?

HDMI (High-Definition Multimedia Interface) is the first industry-supported, uncompressed, all-digital audio/video interface. HDMI provides an interface between any audio/video source, such as a set-top box, DVD player, and A/V receiver and an audio and/or video monitor, such as a digital television (DTV).

HDMI supports standard, enhanced, or high-definition video, plus multi-channel digital audio on a single cable. It transmits all ATSC HDTV standards and supports 8-channel digital audio, with bandwidth to spare to accommodate future enhancements and requirements.

Who supports HDMI?

The HDMI Founders include leading consumer electronics manufacturers Hitachi, Matsushita Electric Industrial (Panasonic), Philips, Sony, Thomson (RCA), Toshiba, and Silicon Image. Digital Content Protection, LLC (a subsidiary of Intel) is providing High-bandwidth Digital Content Protection (HDCP) for HDMI. In addition, HDMI has the support of major motion picture producers Fox, Universal, Warner Bros. and Disney, and system operators DirecTV, EchoStar (Dish Network) as well as CableLabs.

What companies are making HDMI-enabled products?

Please see the list of HDMI Adopters and Test Equipment Makers here on the HDMI website.

How do consumers benefit from HDMI?

The new HDMI digital interconnect provides: Superior, uncompressed digital video and audio quality Simple, user-friendly connector that replaces the maze of cabling behind the entertainment center Integrated remote control A popular interface enabling the transmission of high-definition content. HDMI opens the floodgate of digital content from major motion picture producers

When was the HDMI specification released?

The HDMI 1.0 specification was released in December 2002. The HDMI 1.1 specification was released in May 2004.

What is the life expectancy of HDMI?

HDTV uses less than 1/2 of HDMI's available 5 Gbps bandwidth. With capacity to spare, HDMI can incorporate new technology advancements and capabilities long into the foreseeable future.

How can I get the HDMI 1.1 Specification?

You can click here to order the specification. Interested parties may now obtain a copy of the specification for review at no cost. However, parties must sign the appropriate Adopter or Test Equipment Maker Agreement prior to developing HDMI products.

HDMI is licensed under reasonable and non-discriminatory terms. The Adopter Agreement or Test Equipment Maker Agreement detailing the licensing terms are available. Please follow the instructions for downloading and submitting the appropriate agreement along with your payment in order to obtain a license to the Specification.

What's the difference between the Adopter Agreement and the Test Equipment Maker Agreement, and which one should I sign?

The Adopter Agreement is offered for those parties that desire to make and sell HDMI-based products such as DVD players, Set-top boxes, TVs, semiconductors, cables and connectors, etc. The Test Equipment Maker Agreement is offered for those parties that desire to make and sell test equipment such as oscilloscopes, wave form generators and other measurement tools designed to assist manufacturers in using the Compliance Test Specification to test their HDMI products for compliance with the HDMI Specification.

Does HDMI provide a secure interface?

HDMI, when used in combination with HDCP, provides a secure audio/video interface that meets the security requirements of content providers and systems operators.

What are the advantages of HDMI over existing analog interfaces such as composite, S-Video and component video?

Quality: HDMI transfers uncompressed digital audio and video for the highest, crispest image quality. All-Digital: HDMI ensures an all-digital rendering of video without the losses associated with analog interfaces and their unnecessary digital-to-analog conversions. Low-cost: HDMI provides the quality and functionality of a digital interface while also supporting uncompressed video formats in a simple, cost-effective manner. Audio: HDMI supports multiple audio formats, from standard stereo to multi-channel surround-sound. Ease-of-use: HDMI combines video and multi-channel audio into a single cable, eliminating the cost, complexity, and confusion of multiple cables currently used in A/V systems. Intelligence: HDMI supports communication between the video source (such as a DVD player) and the DTV, enabling new functionality.

Is HDMI backward-compatible with DVI (Digital Visual Interface)?

Yes, HDMI is fully backward-compatible with DVI using the CEA-861 profile for DTVs. HDMI DTVs will display video received from existing DVI-equipped products, and DVI-equipped TVs will display video from HDMI sources.

Will current HD TVs and set-top boxes using DVI-HDTV be compatible with HDMI devices?

Yes. Currently there are TVs with DVI-HDTV inputs available from a wide variety of manufacturers. These devices will be compatible with future HDMI-equipped products.

What types of video does HDMI support?

HDMI has the capacity to support existing high-definition video formats (720p, 1080i, and even 1080p). It also has the flexibility to support enhanced definition formats such as 480p, as well as standard definition formats such as NTSC or PAL.

What is the Compliance Test Specification?

The Compliance Test Specification (CTS) was developed by the HDMI Founders to assist manufacturers in ensuring the compliance of their products with the HDMI Specification. It consists of numerous tests designed to check for compatibility of various HDMI-related aspects of a product, including audio, video, EDID, electrical signaling, protocols, etc. The HDMI Compliance Test Specification represents the minimum compliance testing required for HDMI products, and it is up to each manufacturer to fully test product functionality and interoperability.

How can I get the Compliance Test Specification?

The 1.0 version of the Compliance Test Specification is available to all parties that have licensed the HDMI 1.1 Specification.

What is an HDMI Authorized Testing Center and how do I contact one?

The HDMI Founders have established Authorized Testing Centers (ATC) where licensed manufacturers can submit their products for compliance testing. Currently, ATCs are located at Matsushita Electric Industrial in Osaka, Japan, and Silicon Image in Sunnyvale, CA, USA. The ATC's can be contacted as follows:

Matsushita Electric Industrial Co., Ltd Format Verification Laboratory Location: 1-15 Matsuo-cho, Kadoma,Osaka 571-8504, Japan Tel: +81-6-6905-4195 Attn: Asaichi Akagi Email: akagi.asaichi@jp.panasonic.com

Silicon Image, Inc. HDMI Authorized Testing Center Location: Sunnyvale, CA USA Attn: ATC Director Email: hdmi-atc@siliconimage.com

Does HDMI accommodate long cable lengths?

Yes. HDMI technology has been designed to use standard copper cable construction at long lengths. In order to allow cable manufacturers to improve their products through the use of new technologies, HDMI specifies the required performance of a cable but does not specify a maximum cable length. DVIGear now manufactures long-length HDMI cables up to 20 meters and expects to have a 30 meter cable available soon. As semiconductor technology improves, even longer stretches can be reached with fiber optic cables, and with active cable technologies such as amplifiers or repeaters.

Courtesy of HDMI Licensing, LLC