HDMI: It’s Hard to Know Ye

By John Sciacca

Today (February 3, 2010), the HDMI Licensing group announced that the 3D portion of the HDMI 1.4 Spec is available for download (www.hdmi.org). Steve Venuti, president of HDMI Licensing, commented, ”The HDMI Consortium recognizes the importance of standardized 3D formats for movies, gaming and broadcast content and the need for non-adopter companies and organizations to have access to that portion of the HDMI Specification. As the mainstream adoption of 3D is gaining momentum and content providers define and expand their 3D roadmaps, HDMI is ready to support this major market development.”

The press release went on to say that the HDMI Consortium plans on shortly releasing a 1.4a version of the spec which will include updates to the 3D portion of the spec.

If you’ve been involved with the consumer electronics industry for any amount of time at all, you know that standards and, especially cables, change. We’ve seen composite video, S-Video, Component Video, VGA, RGB, DVI (with –I, -D, and –A varieties), and IEEE 1394. But HDMI – which stands for High-Definition Multimedia Interface – has proved to be the moving-est target of them all. Since its inception, the HDMI cable has undergone more changes than Britney Spears.

In case you’re curious, these are the changes that each version has added, and what we can look forward to – at least for now – when the 1.4 spec finally hits the street.

HDMI 1.0 –Released December 2002. Intended to be a single cable replacement to DVI cables, supporting video up to 1080p/60 Hertz with HDCP copy protection, along with 8 channels of LPCM/192 kHz/24-bit audio. The ability to carry audio was the biggest difference from DVI cables, which were video only.

HDMI 1.1 – Released May of 2004. Added support for DVD-Audio soundtracks.

HDMI 1.2 – Released August 2005. Added support for SACD audio.

HDMI 1.2a – Released December 2005. Specified Consumer Electronic Control (CEC) features, commands and compliance tests, allowing (in theory) all devices to communicate and control each other.

HDMI 1.3 – Released June 2006. Increased bandwidth to 340 MHz (10.2 Gigabits per second) and added support for Deep Color with 30/36/48-bit xvYCC. (Previous versions supported up to 24-bit.) Also supports output of Dolby TrueHD and DTS-HD Master Audio and incorporates automatic audio syncing with video capability (lip sync).

HDMI 1.3a – Released November 2006. Mostly “housekeeping” fixes and specifications for manufacturers. It did add support for streaming SACD in bitstream rather than raw DSD format used in previous versions.

HDMI 1.3b, 1.3b1 and 1.3c – Released Mary 2007, November 2007 and August 2008 respectively. Describe testing and products based on the 1.3a spec and the Type C Mini connector and active cables.

HDMI 1.4 – Increases maximum resolution to 4K x 2K, supporting much higher pixel counts than 1080p (up to 4096 x 2160 at 36-bit). Will allow Ethernet over HDMI, for 100 Mbps connection between connected devices. Also adds an audio return channel, allowing your TV to send audio back to your A/V receiver. Of course, it will also support 3D as announced today, with stereoscopic, 1080p images.

The only real bummer is that older gear likely won’t be upgradeable to the new spec, so enjoying 1.4 (and beyond) will require purchasing new hardware – Blu-ray, TV, A/V receiver – instead of just upgrading firmware.