High-Definition Multimedia Interface (HDMI)
HDMI stands at the pinnacle of the historical attempt to create recording of high similarity between the original and the recorded. This is the phenomenon referred to as Hi Fidelity or Hifi for short.
Original material comes in analogue waves which have to be converted to a stream of numbers (binary) using an ADC (analogue wave converter). Thus the data are now recoded into a binary format and are now referred to as digitalized data. Compression of digital data is a procedure carried out to reduce the transmission bandwidth of the digitalized data.
Why we need HDMI?
With a High Definition Multimedia Interface, the need for this compression is removed because it has the capacity to transmit uncompressed digital data.
There has been a long battle between quantity and quality in terms of compressed digital data. Compression is a necessity of dealing with size, but unfortunately, depending on the method used, quality is often lost in the process. However, the HDM interface provides a console that makes this unnecessary. This is because with HDMI, it is now possible to transmit uncompressed digital data. This means that quality is no longer sacrificed for reduced manageable quantity. Data can now be transmitted in their real-life color, an amazing phenomenon made possible by the advent of this interface.
HDMI represents a viable alternative to previous analogue models like the RF (radio frequency), coaxial cable, composite video, S-Video, SCART, component video, D-Terminal, and VGA. This is because using a single cable, it supports all TV and computer formats!
What systems use HDMI?
Though a recent development of the decade it has enjoyed global acceptance. Within five years of its introduction, almost 1000 consumer electronics and PC companies have adopted its use. It is now common place the term “HD ready” to be associated with several consumer appliances such as to TVs (HDTV), camcorders, still digital photographs etc.
What features are offered by HDMI?
On a single cable, it supports all known TV and PC formats offering up to 8 channels of digital audio channels and the versatile Consumer electronics control signal (CEC).
What are the possibilities of HDMI?
The following features of the HDM interface confers certain immediate capabilities:
- CEC: Consumer Electronics Control: this is an incredible advancement that came with this device. With the Consumer electronic Control console, it allows all your compatible devices to communicate with each other. In simple terms, this means that you can control all your HD devices using a single remote control!
- Enhanced and high-definition video: this is perhaps, the most important hurdle overcome by the HDMI because it is compatible with all TV and PC formats.
- Digital Visual Interface (DVI) compatibility: the DVI transmits information as binary data (numbers). This enables the data to be transmitted in “native resolution”. The pixels are in perfect synchrony of the old analogue systems. Many consumer electronic products already use the DVI. Now, the fact that it is compatible with the DVI interface means no conversion is necessary. The advantage of this is that there is no loss of video quality. All that is necessary is the use of a DVI-to-HDMI adapter.
- Uncompressed Connection: because it is an uncompressed connection, it is independent of traditional TV formats like ATSC and DVB so it can easily be used with these devices.
Current trends in HDMI
With the latest introduction of the HDMI version 1.4 in June 2009 came the new phenomenon of frame packing. Frame parking is a 3D transmission format that packs Left and right images into one video frame thus this doubling the bandwidth.
Frame packing is the future of 3D transmission and will one day be the only acceptable format.