By Jeff Su

Background:

As the HDTV market continues to heat up, consumers are in need of being educated on the latest technology. One of the terms that you, the consumer, will surely run into while selecting a HDTV set is: HDMI. For most this is an unfamiliar term and we will explain the details of HDMI in this article so you, the consumer, is armed with the proper knowledge to make intelligent purchasing decisions.

What is HDMI: HDMI is an acronym for High Definition Multi-Media Interface. The HDMI specification (now at 1.2) was created by some of the largest consumer electronics manufacturers in the world: Hitachi, Matsushita, Philips, Silicon Image, Sony, Thomson, and Toshiba. HDMI is the latest digital HDTV interconnection standard. The notable differences between HDMI and the earlier HDTV interconnects standards (component video, and DVI) are:

-HDMI is all digital unlike analog component video cables

-HDMI supports multi-channel audio in addition to digital video. (DVI only supports digital video)

- HDMI is more compact in size and carries both audio and video signals therefore eliminate cable clutter.

-HDMI incorporates content protection called HDCP ( high definition content protection)

What does a HDMI connector look like: HDMI looks similar to a USB cable. The compact size and high integration (carries both audio and video) makes the HDTV installation experience truly “plug and play.”

Why should I use HDMI:

-HDMI is all digital, so picture quality is “perfect” from source to display

-HDMI is both a digital audio and video connection. This will minimize cabling in your system

-HDMI is rapidly becoming the de facto standard for HDTV connections.

How does HDMI transport the digital video: The video portion of HDMI is carried by 3 separate differential pairs. Each pair transports 1 of 3 uncompressed native digital R,G, B signals from source ( dvd player, set top box) to the sink ( HDTV display). A unique protocol, T.M.D.S.( transmission minimized differential signaling), is used to transport the digital data. Each pixel is represented by 24 bits ( 8 bits each for each of the primary colors). The T.M.D.S. protocol then “calculates” and stuffs 2 extra bits to the video data stream in order to create a digital stream with minimum transitions ( lower EMI, lower interference) and also minimize long strings of ’1′ and ’0′ which can cause detection errors.

A fourth differential pair, called the TMDS clock provides the pixel clock for timing the data stream. The maximum TMDS single link pixel clock rate is 165 MHz.

What is the data rate of a single link HDMI connection: The maximum pixel clock rate is 165MHz and each of the 3 TMDS video streams carries 10 bits. Therefore the aggregate data rate is 3 x 10 x 165MHz = 4.96Gbps.

How many pins are included in the HDMI connector: There are 19 individual pins in the HDMI connector. There are 3 pairs of TMDS signals which carry all the digital audio and video signals.

How is the digital Audio signal transported: The multi-channel audio is time multiplexed into the TMDS data streams. Audio is much lower data rate (192kbps) and the extra time is used to demux the audio signals.

What is HDCP: HDCP is an acronym for High-Bandwidth Digital Content Protection. HDCP is an encryption method developed by Intel in order to control unauthorized copying of digital media. The encryption is carried out in the HDMI transmitter found in the “source” ( dvd player, set top box) and decryption is carried out by the HDMI receiver ( the HDTV display). The secret keys for encryption are exchanged between the source and display over an I2C bus ( pins 15 and 16).

Is HDMI compatible with DVI: DVI is the predecessor to HDMI. HDMI and DVI are identical as far as video is concerned. Therefore, video backward compatibility exists. However, DVI will not support digital audio. For example, if you have an older DVI connection on your source and a HDMI connector on your display, a HDMI to DVI cable is all that is needed in order to view the video. A separate audio cable ( TOSLINK or SPDIF) will be needed to carry the digital audio.

What formats will HDMI support: HDMI is high speed digital connection and will support resolutions of 480i, 480P, 720i, 720 P, 1080i and in the future,1080P.

Conclusion:

HDTV technology is changing rapidly. HD connections such as HDMI will become the de facto standard in HDTV connections. We have outlined the important features of HDMI, so the consumer is well informed and ready to make intelligent purchasing decisions.

Jeff Su is product development manager at http://www.octavainc.com. He can be reached at info@octavainc.com

Article Source: http://EzineArticles.com/?expert=Jeff_Su

By Jon Martin

In the world of digital audio, there are two types of cable to choose from; optical cables which use light to transmit signal and digital coaxial cable. These audio cables will enable your home theater system to transmit digital data between components. This will provide you with superior sound quality over typical RCA audio cables.

How Digital Coaxial Cable Works

Digital coaxial cables employ the same principles as other coaxial cables. The inner conducting layer is surrounded by an outer conductor as well as the rubbery insulating layer outside the cable. The digital signal is sent through the inner conductor as it travels between components. During the course of its transmission, the signal routinely comes in contact with the outer conductor. The outer conductive layer is created with materials that act as a reflector for the signal, thereby bouncing it back off of its surface. The signal will continue to reflect within the confines of inner conductor until it reaches the receiving component.

Dedicated to Digital Audio

Digital coaxial cable has only one purpose; to deliver digital audio between components. This is in complete contrast to RF coaxial cable which transmits both video and audio along the same path. As you may suspect, dedicating the entire bandwidth of the cable to sending only digital audio has excellent ramifications for your home theater’s sound quality. This practice results in greater signal fidelity between the transmitting device and the receiving component. Greater signal fidelity means that the sound you hear from your home theater speakers will be truer to the way the sound was originally recorded.

Benefits of Digital Coaxial Cables

Digital coaxial cable also has another benefit related to its dedication to digital audio. In the manner that signal transmission usually takes place, the digital signal from the source, a DVD for example, is sent to a digital-to-analog converter (DAC). The signal is converted to analog and sent through the given cable where it reaches the receiving component on the other side. This component uses an analog-to-digital converter (ADC) to reconstruct the digital signal as closely as possible. During this process, errors and variations can be introduced to the signal resulting in audible artifacts and distortions that diminish your home theater’s sound quality.

Unlike with other audio cables, digital coaxial cable can transmit digital signals along its length without the need to convert to analog. Digital coaxial cable is capable of by-passing this process and delivers a cleaner signal to your home theater receiver.

Applications of Digital Coaxial Cables

Connections for digital coaxial cables can be found on everything from DVD players to home theater receivers. If it uses digital audio, then chances are there is a manufacturer who has made that component with digital coaxial cables in mind.

Jon Martin is the Webmaster of the Home Theater Accessories Resource. The Home Theater Accessories Resource is your guide to home theater accessories.

This article came from the Connecting Home Theater Components section of the site.

Article Source: http://EzineArticles.com/?expert=Jon_Martin

By Douglas Taylor

You will need software to record and stream your audio on your website. With so many choices it is hard to know which way to turn. How are you to know which software programs will meet your needs? Today we will look at some of the more popular and inexpensive programs that are available today.

Audacity: You may do well to start with the free to download software Audacity. This is an unbelievable program especially since it is free. You may find Audacity will meet your entire computer recording needs.

n-Track Studio; n-Track Studio is computer audio recording studio that offers a lot of features. You can download an evaluation version to see the power this program has at their website.

Sound Forge: This program includes a powerful set of tools to record and edit your audio. This audio editor will get the job done for almost any streaming audio situation.

Wave Lab: I love Wavelab; it has been my audio editor of choice for many years now. It has always done anything I have asked of it. The problem with the program is that it is too expensive for the average consumer. This has been solved with the addition of Wavelab Essential. This program gives you a great amount of the power of Wavelab at a bargain price. I can’t recommend Wavelab enough.

DB Power Amp: This cool program converts your audio files to the mp3 format or to wav. I use this program on a daily basis to convert my audio over. This program just works. It is simple to use and you will wonder how you got along without it. The price they charge for this software is a true bargain.

Hotsquad.com: This website is a virtual goldmine of free and inexpensive software and a whole lot more. If you have not been to the website before you need to get yourself a cup of coffee and spend some time exploring. The information here is unbelievable.

Doug Taylor has been creating audio online since 1999. If you think that putting audio files on a website will be a lot of hard work and hassle then download a free 16 page special report Mastering Streaming Audio.

Visit http://www.create-streaming-audio.com/csa_ezine.html for streaming audio tips, tricks, shortcuts, and techniques.

Article Source: http://EzineArticles.com/?expert=Douglas_Taylor