What is HDBaseT?
HDBaseT is the name given to a technology designed to facilitate the interconnection of high-definition multimedia sources and sinks using a single category cable as the physical connection. The standard was published in 2010 by the HDBaseT Alliance, a group composed of founding members LG, Samsung, Sony and Valens.
HDBaseT was created as a long distance AV connectivity solution to extend HDMI and DVI-D technology. With the effective range of a native HDMI connection limited to just a few tens of meters, there is a clear market demand for a single standard, simplified connection that can transport high-definition audio-video content at least 100 meters, thus complementing the TIA 568 standard for telecommunications cabling systems.
HDBaseT is designed to deliver a feature set known as 5Play. HDBaseT technology allows for integrated transportation of uncompressed HD video, up to eight channels of digital audio, 100BaseT ethernet, control via RS232, CEC, IR, and USB, and up to 100 watts of power for connected devices. These five functions address almost all of the common connectivity demands associated with the installation and integration of contemporary high performance AV systems, whether they are consumer or commercial in nature.
The HDBaseT Alliance released an HDBaseT 2.0 standard on August 13, 2013. This updated standard includes provisions for an HDBaseT-Lite variant that will trade the full 100 meters of potential connectivity for a maximum 70 meters with fewer features and lower power, but selling for a reduced price. The HDBaseT 2.0 standard also included, in its full size version, provisions for a modified USB 2.0 integration and support for UltraHD connectivity.
HDBaseT uses a multi-level pulse-amplitude modulation system to transport uncompressed video data where-in each symbol transmitted (this is specified in baud) represents sixteen discrete voltage levels and each of those levels represents four bits of data.
It has been noted that, because of the intense amount of data involved in these connections, that HDBaseT cabling may be susceptible to crosstalk when installed in a bundled environment. C2G tests have found that, for the most dependable installations, use of Cat-6 shielded cable is the best choice for systems that are going to push the maximum distance of 100 meters at 1080p resolutions. Systems intended to scale to UltraHD should be built with Cat-6a. Systems limited to 70 meters or less, and especially those employing HDBaseT-Lite performance expectations, may at times be effectively installed with Cat-5e.
What is HDCP?
High-bandwidth Digital Content Protection (HDCP; commonly, though incorrectly, referred to as High-Definition Copy Protection) is a form of digital copy protection developed by Intel Corporation to prevent unauthorized duplication of digital audio and video content as it travels between devices in the last 100 meters of an installation.
The proliferation of digital audio and video content brought with it a somewhat unexpected problem. In the analog domain, every time a copy is made of a program a little bit of the quality of the content is lost. Noise is added and detail is softened, so the copy is obviously inferior to the original. This isn’t true in the digital world, where a copy of the 1’s and 0’s that make up the data is essentially an indistinguishable clone. To protect the rights of the content owners (often referred to as “digital rights management”), a system that effectively hindered illicit copying was needed.
There are a number of copy protection systems that operate at the programming level. They range from conditional access systems deployed in large-scale satellite network broadcasts to CSS, AACS, and other proprietary systems that protect content during delivery. A single system is necessary, however, to provide a standardized content protection scheme while the content is being transferred from its source device (satellite receiver, cable set-top box, DVD player, or streaming media player such as TIVO or PS3) to a display device. HDCP fulfills that role. It is managed by Digital Content Protection LLC, a division of Intel. HDCP compliance is ubiquitous, global and mandatory if protected content is to be legally accessed. What’s more, there is no legally permissible way to convert HDCP encrypted content back to an analog (unprotected) state; this is clearly stated in the Digital Millennium Copyright Act of 1998.
HDCP uses a cryptographic technique known as Blom’s Scheme, a form of threshold secret sharing. In HDCP systems each device has both a secret key and a public identifier. When both devices successfully exchange public keys, they are able to create a shared key for communicating. This is what is meant by “key authentication and exchange.” As you might surmise, HDCP compliance is impossible with an analog connection or analog device attached to the system.
Source devices like TIVO DVR’s, DVD players, laptop computers and satellite receivers all use HDCP copy protection to prevent illicit duplication of encrypted content. Obviously, displays such as LCD flat panels, projectors, and plasma screens (collectively known as “sink” devices) must have HDCP compliance capability for the system to work. A third class of devices such as switchers, selectors, extenders, and splitters (collectively known as “repeater” devices) also have HDCP components. One of the inherent abilities of HDCP is that it can examine every device connected to the AV network and prevent any transmission of signal if even a single device is found to be noncompliant.
There are two possible responses an HDCP enabled system can exhibit when faced with attached noncompliant components. The system can show the content with a highly reduced resolution (480i) if the content is encoded with an Image Constraint Token (ICT). Alternately, the system can show a blank screen (typically solid blue or black) if the content is encoded with a Digital Only Token (DOT).
What is MHL?
Dr Martin Cooper, working for Motorola, made the first recorded call using a technology we would later know as the cell phone in April of 1973. By 1977, AT&T and Bell Labs had constructed a prototype cellular system. Ten years later, in 1987, the community of cell phone users would break the one million mark. Today there are an estimated 6.8 billion cell phones in use worldwide. Some estimates indicate more people have access to cell phones than have access to modern toilets.
An MHL dongle
With all this cellular mobility, one area ripe for change is the integration of cellular and mobile devices in fixed AV installations. Until now, the idea of watching content on a large TV that is sourced from a cellular device has been largely untapped. At the 2008 CES, Silicon Image demonstrated the first generation of a system called “Mobile High Definition Link,” the technology that would ultimately be the basis for MHL. The MHL Consortium was founded in April 2010 by Nokia, Samsung, Silicon Image, Sony, and Toshiba and by 2011 the first MHL-enabled products began to make headway into the marketplace.
MHL is a TMDS-based protocol that allows a mobile device to interface with a modern projector or flat panel display by using an HDMI connector (but not using an HDMI signal). The latest specification (3.0) supports UltraHD video (up to 3840x2160 at 30fps) and 7.1 channel surround sound, as well as support for peripherals like a keyboard or mouse to control and power the device.
Today there is an installed base of more than 330 million MHL enabled products from more than 200 adopters, including cell phones and tablets, AVRs, DVD players, laptop docks, displays, and projectors in use. MHL market penetration is expected to grow to more than 1.2 billion devices by 2016.
To see if your cell phone, flat panel display or AV switch is MHL compliant, go to this list of MHL enabled products.
What is Miracast?
If you’ve been in this business for a while, you’re likely familiar with Apple TV. Perhaps you’ve even installded an Apple Airplay system. AirPlay is a proprietary protocol developed by Apple that allows wireless streaming of audio, video, and metadata between devices.
Apple’s Airplay provides for “mirroring” the screen image of select Apple devices through a connection made via a Wi-Fi (802.11 a/g/n) to an Apple TV receiver on the same network. While this is a unique, useful and enjoyable feature to have, its weakness in institutional applications is that it requires devices to be added to the LAN. Without careful management, those devices may compromise network security and add to the network’s data load. In a residential network with just a handful of devices this is easy to control. In a commercial environment with dozens, or hundreds, of rooms and tightly controlled network access, it’s not such a friendly installation.
Enter Miracast. Unlike Airplay, Miracast creates a peer-to-peer direct connection similar in user experience to a Bluetooth connection. Without the need to access the LAN, there aren’t problems with network security or capacity and data rates. Miracast technology securely delivers up to 1080p HD video and 5.1 surround sound content to or from desktops, tablets, mobile phones, and other devices by leveraging 802.11ac radio frequencies without having to connect to the LAN.
Miracast is built on the Wi-Fi Direct platform created by the Wi-Fi Alliance. Wi-Fi Direct allows source and display devices to discover one another and provides the underlying device-to-device connectivity for Miracast. Miracast builds upon Wi-Fi Direct with mechanisms to negotiate video capabilities, setup content protection (if needed), stream content, and maintain the video session. Miracast is an HDCP compliant, industry-wide solution that offers compatibility across brands and devices. It’s easy to set up and use since the devices choose the appropriate settings automatically. There are many devices that come with Miracast connectivity built-in. Check this list of compliant mobile devices and this list of compliant displays to see if your system supports Miracast. For display devices like projectors and flat panels that aren’t Miracast enabled, stand-alone receivers are now available.
What is UltraHD?
Ultra HD is part of the next generation of video technology. Today we watch high definition video content in a format known as 1080p. This means that the image has 1080 horizontal lines of pixels (picture elements) stacked on top of each other in a manner roughly analogous to the logs in the wall of a log cabin. There are 1920 individual pixels (think “dots”) lined up next to each other on each scanning line. We often refer to this as a 1920x1080 image.
If we multiply 1920 pixels times 1080 scanning lines we come up with 2,073,600 discrete pixels composing the image. Therefore there are approximately 2 million “dots” making up the picture you see. The “p” in 1080p indicates a progressive scan implementation where-in the full frame of pixels is shown 60 times (50 times in Europe) every second. This system is sometimes referred to as a D2K image (D for digital and 2K for approximately 2,000 pixels in each horizontal scanning line).
When we try to move to even higher definition pictures, we keep the same relationship but increase the pixel density. The industry is now moving toward widespread adoption of D4K (standards also being developed for D8K) images. Roughly speaking, a D4K picture (sometime written as simply “4K”) has twice as many pixels in each horizontal scanning line, and twice as many horizontal scanning lines. Following the same logic used above, a D4K image has 2,000 scanning lines composed of approximately 4,000 pixels each resulting in (2,000 x 4,000 = 8,000,000) about eight million pixels of resolution, four times the resolution of today’s already outstanding HD televisions.
Several 4K resolutions exist in digital television and digital cinematography. In October 2012, the Consumer Electronics Association (CEA) announced that the official term “Ultra HD” would be used for any display with a 16x9 ratio with at least 1 digital input capable of a minimum resolution of 3,840x2,160 square pixels. This delivers a stunning 8.3 megapixels (8,294,400 to be exact) with a widescreen aspect ratio of 16:9. UltraHD images are only delivered in a progressive scanning manner (there are no official interlaced D4K standards) at frame rates of 120p, 60p, 50p, and 30p.
While we will have to integrate new source devices that can generate these terrific data rates with a new generation of flat panel LCD and projection displays, we won’t be seeing any new connections. D4K and UltraHD content is supported by HDMI, DisplayPort ++, and HDBaseT connections.
What is WiDi?
WiDi is a trade name for Intel Wireless Display technology. Intel unveiled this AV connectivity system at the January 2010 Consumer Electronics Show (CES). WiDi technology is now in its fourth generation, but both consumer and commercial industry awareness and acceptance of the technology remains low. Intel’s WiDi software is not supported by Apple Mac devices, but it is included in most Windows 7 and nearly all Windows 8.1 OS products, including tablets and phones. Apple and Android smartphones and tablets can connect to a WiDi receiver or WiDi enabled display by using an app such as Intel’s Pair & Share or (for Android only) by using Intel’s TelePort Extender.
WiDi creates a peer-to-peer direct connection between devices without the need for a wireless access point or router. Device such as smartphones, tablets, AV receivers and display monitors typically have the inherent ability to connect to an 802.11 wireless network access point in order to leverage Internet functionality and feature sets. WiDi leverages this existing hardware ability through the use of an embedded software access point (soft AP) in the device’s operating system. When a WiDi device (Tx) enters the range of a WiDi display (Rx), it can connect with that device directly. Connection and setup is simplified and is similar to a Bluetooth user experience.
WiDi operation takes place using 802.11n duplex radio communications between the transmitting source and receiving sink. It’s vital to recognize that this communication link does not leverage, nor does it need network access. While the connection uses 802.11n-2009 connectivity and protocols in the 2.4 GHz or 5 GHz frequency bands, the com link is direct from device to display.
Intel mandated inclusion of WiDi technology in many industry products. At the 2013 CES show, Intel announced that companies which use the Ultrabook name or new fourth Generation Core vPro Haswell internals must include Wireless Display as standard. To further improve market penetration, Intel created a Pro version of WiDi specifically tailored for enterprise applications. WiDi Pro supports the expected “duplicate mode,” where the same content appears on the laptop screen and the presentation display at the same time. However, in many professional applications it is sometimes necessary to present the audience with one screen while simultaneously referencing speaker’s notes on another, for example. This is an “extended mode” and it’s also possible using WiDi and the WiDi Widget app for PC.
WiDi 3.5 is the technology upon which Miracast is based and Miracast is backward compatible with most WiDi features.