All of the digital advancements mentioned are but the tip of the iceberg in the digital revolution. Digitization of content is reaching into other categories, such as cameras and camcorders, fueling cycles of growth and opening up new possibilities for the consumer to create content. The digital conversion holds great promise for the content community, manufacturers, and consumers alike.

What is Digital? An Exploration of Terms and Usage

Consumer Electronics Association | Consumer Electronics Association

What is Digital? An Exploration of Terms and Usage
Prepared by: Consumer Electronics Association
Reproduced with Permission

All of the digital advancements mentioned are but the tip of the iceberg in the digital revolution. Digitization of content is reaching into other categories, such as cameras and camcorders, fueling cycles of growth and opening up new possibilities for the consumer to create content. The digital conversion holds great promise for the content community, manufacturers, and consumers alike.

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What is Digital? Marketing Term or Technical Reality

Everything is labeled as digital today. We have digital television, digital radios, digital music, and digital toasters. You name it, somewhere; someone has attached a digital label to it. So many things come with the digital designation the true concept of what digital actually is has become diluted over time. Parallels in the food industry are plentiful; descriptors like 'natural', 'light', or 'organic' are often used to tempt consumers. At some point the true meaning of the words are lost and the terms become bland marketing jargon with no real punch.

Consumers have come to equate digital with a mark of quality and technical currency when ultimately it means something much more basic. Digital has become an overused term, and is misapplied in some cases. This has lead to confusion among consumers about what digital really means and what it truly provides to them.

Just 1's and 0's - Analog World, Digital Storage/Transmission

We live in an analog world. Our eyes receive light waves bouncing off of or emitting from an object, which our brains perceive as an image. Sounds are experienced through sound waves traveling to the ear. The digital world is merely an interpretation of this analog reality. Digital is a language based upon 1's and 0's used to represent pictures or sound. Though binary numbering systems were originally created as a way for computers to communicate, many digital languages now exist, some for audio and some for video. At its heart, digital is still the language of silicon-based machines.

The beauty is, digital languages pack audio and video information into a smaller space than a similar analog through the process of translation, also known as compression or encoding. After encoding, the now digital content takes up less storage capacity and requires a smaller pipeline for transmitting. For us to hear or see the images on the receiving end our devices must translate, or decode, the digital message back into the analog waves our senses can perceive.

Another feature of the encoding process is the possibility for copyright protection. Because the sound and light waves are translated into a foreign language, content can be protected (encrypted) from undesired usage (pirating). Extra information or a jumbling of the 1's and 0's allow only those with the right translation key to see or hear the stored content.

"A digital file is more accessible than its analog counterpart since it has a beginning and an end measurable by space rather than just time."

A final benefit is the modular nature of digital content. Once converted to digital, the actual content comes the closest to being a physical entity that can be moved around at will. The most appropriate image is one borrowed from the PC industry; digital content stored as a file can be manipulated in virtual space. A digital file is more accessible than its analog counterpart since it has an end and a beginning measurable by space rather than just time. This lets consumers quickly jump to the beginning of a file through an address not tied to time. They also can move the content to another device without having to play it back and simultaneously record. This is the most powerful aspect of the digital language and the one inciting the most fear among content owners. Modularization makes control over the content more difficult.

And yet digital in its most technical sense is no more and no less than a series of numbers.

Digital and Quality are Not Synonymous

Over time, and through persistent marketing efforts, digital has come to mean more in the minds of consumers. Many consumers believe that digital denotes quality. While in many cases, digital formats do provide an improvement in the quality of the content stored or transmitted, this is not guaranteed just because something is translated into the digital language. In short, digital is not a measure of quality and not all digital content is created equal.

The challenge with digital content is everyday sights and sounds are made up of massive amounts of information, so that any given recording process can only hope to capture a portion. Digital encoding is subject to information loss since analog waves are translated and compressed into a different language. Some information is retained and some is lost during this process, depending on the amount of compression. Linguistic purists throughout history have lamented the lost context and meaning resulting from translating works of literature from the original language to another. The same is true for audio and video purists when describing some forms of digital translation.

Information loss does not mean realism and quality are disregarded in the creation of the digital language. Quite the opposite is true. In the field of digital encoding, the issue of retaining the quality and depth of the original sight or sound is forefront in the minds of technologists and engineers. The industry continues to make progress on maximizing the amount of information stored. The end product is a host of encoding standards with varying degrees of retained information vis-à-vis the original content. Some standards produce more 'lifelike' performances than others. The level of quality has more to do with the format used than its digital nature.

Digital Content: A Timeline

1982     The first compact disk players are available for sale in the U.S.
1984     The CD-ROM is introduced.
1989     MP3 is patented.
1990     Digital audiotape (DAT) makes its debut.
1991     Multimedia CD-ROM computer systems are introduced.
1992     Digital phone service emerges.
            Digital compact cassette (DCC) is first marketed.
1993     The first wireless headset portable CD player is marketed.
1994     Digital broadcast systems (satellite TV) are introduced.
1995     The first digital video (DV) camcorders are sold.
            Digital cameras hit the market.
1997     DVD comes to market.
1998     The first digital televisions are sold in the U.S.
            The DVD-Audio format is agreed upon.
            Recordable DVD formats emerge.
            The first portable DVD player is introduced.
1999     Portable MP3 players begin to sell.
            DVD Audio and SACD players are introduced.
            Personal video recorders (PVR) are first introduced.
2000     DVD recorders begin to sell in the U.S.
2001     Digital satellite radio enters the market.

As the digital transition progresses for both audio and video content, different digital formats and encoding methods are emerging. Each format adds a new dimension, such as increased portability or quality, to the digital rendition of content. Audio and video content are at different stages in this transition.

Digital Audio

The digital era began with audio. With the birth of the CD in the early 1980's, the industry saw its first widely accepted digital translation of content beginning the transition to digital. Though other formats, such as DAT, tried to offer other methods for digital storage of music, the CD truly won over the consumer. The audio market now leads the digital charge with the majority of audio playback and storage devices handling digital formats (figure 1).

Like all digital technologies, the CD, or compact disc, is a medium for storing content in the digital language of 1's and 0's. The CDs digital language was developed by Sony and Philips in 1981 based upon a sampling rate of 44.1 kHz (essentially a measure of how much information is retained in the recording). According to the standard, content is 'burned' onto a plastic disc using a red laser. Though criticized by some audiophiles attuned to the sound of an analog turntable, the CD has largely held up as an improvement over cassette tape in terms of clarity and durability.

Initially a high-end stereo component, the CD has brought the digital audio transition to the PC, into the car, and onto portable devices. The additional ability to record on CD in the late 1990's has helped to expand its reach. The CD now is the accepted medium of choice for data and music with 40 percent of households owning a CD burner.

The MP3 format emerged in the early 1990's in response to the low bandwidth environment of the early dial-up Internet, even though it ended up further expanding the usefulness of the CD. MP3, standing for Motion Picture Experts Group Audio Layer-3, utilizes compression techniques to squeeze audio content into small packets. The effect is captured in a measure of the effective bitrate of the file, which reveals the amount of information captured in one second of sound. Thus a 64 Kbps file contains 64 kilobits of information in one second of sound. A higher number means the sound is more realistic and true to the original. A person producing MP3s can choose among a variety of bitrates at the time of the recording, thereby determining its quality. The typical range is from around 24 Kbps on the low end to 320 Kbps on the high. Most times a bitrate of 128 Kbps is considered adequate for decent quality audio.

MP3 encoding enables ultimate portability and transmissibility to music since it now can be manipulated as a file. Other competing standards now exist, such as Windows media (WMA) and Real Audio (RA), but none are quite as pervasive as the MP3. The debate rages over which produces the best recording, however.

The MP3 format can truly be described as a consumer phenomenon. Well over half the Internet population has engaged in the downloading of at least one MP3 file. Many do so on a regular basis both for sampling music or sharing it with friends and family. The process of 'ripping' a CD to MP3s of the individual tracks has also become more widespread. Pairing MP3's with the recordable-CD as the 'burning'/storage technology has sparked a revolution in music. According to surveys conducted by the Consumer Electronics Association (CEA), consumers prefer the CD for storing compressed and uncompressed music files. This trend now is forcing the music industry to re-evaluate business models to accommodate for the new market realities.

The music industry is challenged by the lack of security features built into most MP3 recordings, as well as the relative ease of ripping and burning content. Consumers want to be able to make music compilations and engage in other fair use activities just as the content community wants fair compensation. Keeping these rights in balance will be a challenge going forward.

Despite the legal questions, consumers love the format. Perhaps most important is its use for creating music mixes - a practice started long ago with the advent of tape. To the horror of many audiophiles, the majority of MP3 users also like its sound quality. Three quarters of users responding to a CEA survey rated the sound quality of MP3 recordings as at least CD-quality. MP3 is the people's champion. Newer versions of MP3, offering even higher sound quality are the next step.

Consumer's interest in MP3 has sparked many new forms of hardware for playback. The portable MP3 player, based on hard-drive and/or solid-state memory, is one product. Though still over shadowed by the CD, approximately five million MP3 players have sold since inception, with nearly a million units expected to sell in 2002. MP3 playback is also making its way into the car and the home stereo as devices become enabled with hard-drives or portable media slots. This trend is likely to fuel a strong upgrade cycle for both the aftermarket autosound and home theater markets during the next several years.

Somewhat overshadowed by the hype surrounding MP3, are other advancements in the domain of pre-recorded digital music. Seeking to take digital music to the next level, beyond the CD, companies have developed formats offering even higher quality and more realistic sound. These are Super Audio CD (SACD) and DVD-Audio. While the CD was built around a 44 kHz sampling rate, each of the new standards preserve more of the original aural information by offering sampling rates of 100 kHz and beyond. They also bring true multi-channel surround sound to the consumer. As a result of the large amounts of audio information to be stored, both formats rely upon the larger storage capacity of a DVD.

Though yet to gain traction among consumers still fixated on MP3 and CD, there appears to be a grass roots level of interest in SACD and DVD-Audio. Surveys and focus groups performed by CEA show a willingness to at least consider the new sound formats as a future option. The research also points to the surround sound experience as a key benefit to consumers.

Digital Video

The digital transition is only just beginning to gain steam on the video side of the house. Where it has, the results are profound. In fact, sales of digital video products are leading the video market in its current cycle of growth as the analog products give ground to their digital descendants. So it is with the VHS and DVD, and with analog and digital television.

The challenge is keeping all of the formats straight in the rapid push towards the digitization of video. The distinctions between formats are sometimes confusing, since many different video standards for digital have emerged. With video more than anywhere else, digital is often confused with quality.

There is no mistaking the impact on quality brought on by a new digital format - the almighty digital versatile disc (DVD). The DVD has brought the digital transition to the mainstream of the video market. Picking up where laserdisc players left off, and building upon the success of the CD, the DVD has met with huge fanfare in the marketplace. With a million units sold in the second year and 20 percent penetration by year four, it now holds the title of fastest growing CE product of all time. Certainly, so much can be said about the implications of the format it deserves its own paper (see CEA's "Ode to DVD: Kind of Recorded Media?").

Figure 3: DVD Projections

The DVD employs digital encoding to capture more audio and video information than is possible on its predecessor the VHS tape. With video products, the level of realism or detail captured is expressed as lines of resolution. The more lines, the better the picture. The scanning method, whether every line from top to bottom in one swipe of the screen (progressive scan), or every other line (interlaced) also makes a difference. A progressive scanned image generally offers better picture quality. For example VHS offers up to 480 interlaced lines and DVD offers 480+ progressively scanned lines, contributing to the superior picture of DVD. On the audio side, VHS offers surround sound derived from a two-channel signal. DVD offers discrete 5.1 channel surround sound, providing an even more realistic three-dimensional sound environment. Both utilize up to six speakers to produce the sound, however only DVD treats each channel as a separate and distinct source on the soundtrack.

DVD's improvements are made possible through tremendous storage capacity and an optical disc type medium. Lower wavelength lasers and multiple disc layers both contribute to the overall capacity. The digital language the discs are encoded in, the MPEG-2 format, also has an impact.

Continued improvements to the DVD are expected over the next several years. The MPEG-2 format is continually being improved to allow more information to be captured in the encoding process. The movement to blue lasers for reading and recording information from the discs will allow more digital information to be captured. This provides even further improvements to the perceived realism of the picture, bringing high-definition video to DVD. In addition, the ability to record is slowly working its way into the mainstream as the industry agrees upon standards and price points come down. All of these advancements help to position DVD as the future format of choice for all digital content, whether audio, video, data or games.

Things are less clear in the TV category. The television industry has created a number of digital encoding methods, each pertaining to different systems. Satellite TV employs a digital mode of transmission. So too does digital cable. New formats for digitally transmitting content over the airwaves also exist. Here again, digital refers to the use of a digital language for representing material. The digital label itself is not to be confused with marks of quality of the content since each format or system delivers different levels of realism through the amount of video information it captures.

In response to the need for defining digital television and providing some measure of quality, the ATSC outlined 19 formats for handling over-the-air digital broadcasts. These formats quickly grew beyond just over-the-air usage and became the benchmarks for anything bearing the DTV label. The ATSC formats now provide the basic guidelines for all types of digital signals. Anything claiming DTV status must have the capability of transmitting a signal that conforms to one of the 19 formats. At the top of the chain and truly driving the digital TV movement, is high-definition television (HDTV), which delivers the best picture quality of all the current ATSC formats. HD offers the consumer a minimum of 720 progressive or 1080 interlaced scan lines. This puts HD beyond even current DVD, which already is offering stunning picture quality. Though digital satellite and digital cable systems are capable of transmitting, and do transmit some HD signals, the majority of HD content is being sent via the airwaves.

Beyond the digital standards, and apart from how the content was recorded, an important factor in determining the quality of the digital video signal is the bit-rate allocated to sending a signal through a carrier such as cable or satellite. Any given digital channel has the capacity for a stream of data roughly 19 mega-bits per second (Mbps) wide. However, the broadcaster or carrier can determine, via the level of compression used, how much of that stream to use up with one signal. If the carrier decides to send the signal at HD quality (720p or 1080i), the full stream can be taken up. Compressing it down to 480 progressive scan lines will only consume a portion of the full stream, leaving bandwidth left over for other signals. This allows broadcasters and carriers to send multiple signals on one channel. On the consumer's program guide these sub-channels or signals will show up as 4-1, 4-2, 4-3, etc. Each of the carrier types, satellite, cable and over-the-air, have different ways of handling the signals and thus applying the standards. This translates into different signal qualities. In each case the carrier is faced with the difficult decision of how best to allocate the available bandwidth - balancing between quality and breadth of content.

Digital cable is the newest digital mode of transmission. Enabled by the cable company's continuous upgrades to fiber optics in many neighborhoods, digital cable is based upon the MPEG-2 encoding standard similar to DVD. Upgrading to digital in many cable systems provides the consumer with enhanced program guides, more channels, and other features, including video-on-demand in the future. In some cases it also provides a better picture quality, depending on how the digital bit stream is allocated. It does not guarantee better quality or that the picture will be at the highest standard of HD. Right now only cable systems in select few markets are passing through high-definition content with hopes this will grow over the near future.

Digital satellite systems (AKA direct broadcast systems or DBS) utilize a satellite and set-top box combination to receive television signals. It also is based upon MPEG-2 compression as the digital language. Though not guaranteeing HD quality signals on all channels despite the digital transmission method, DBS does offer a selection of stations broadcasting in HD. Because of the national footprint of DBS, this provides the broadest exposure to HD content of all the mediums.

Regardless of the method of receiving the digital signal, consumers must have a way of decoding the digital signal back into its analog form for display on a set or monitor. This includes an ATSC decoder (for over-the-air signals) built into the display itself or a separate satellite, cable, or antenna set-top box containing the appropriate digital decoder. A TV capable of displaying the resolution being broadcast is also required. This is where a 'digital' television comes into play. Most of the DTVs sold today are rated to display up to HD quality resolutions. Analog sets on the other hand will only display images up to 480 interlaced lines of resolution, though usually at much lower resolution. When buying a set, consumers should verify the maximum resolution the set is capable of to make sure it matches what they are expecting to watch on satellite, cable, or antenna based systems.

The great news for consumers is the content community is creating more and more digital programming at the highest levels of resolution and sound quality. Carriage of this content also is increasing. This combined with the falling price points of the newer HD sets, is providing consumers with a great incentive to upgrade to HD capable displays and integrated sets. Once purchased and experienced, these consumers look forward to receiving the best possible picture. So far, roughly three million households have made the switch. The digital transition in video is underway and gaining momentum.

Forging Ahead

All of the digital advancements mentioned are but the tip of the iceberg in the digital revolution. Digitization of content is reaching into other categories, such as cameras and camcorders, fueling cycles of growth and opening up new possibilities for the consumer to create content. The digital conversion holds great promise for the content community, manufacturers, and consumers alike. There are hurdles and challenges, including legitimate copyright and cost concerns, but the revenue opportunities and improvements in portability and quality are worth the effort. Part of the marketing challenge in reaching consumers and extolling the benefits of the new digital era is to maintain a clear definition of digital for consumers. To do so will help spur on the transition. To fail will jeopardize adoption and the maintenance of a satisfied and loyal user base. As always, the consumer is the greatest asset and the crux of all product advancement. Keeping sight of this is one of the keys to success in the competitive CE marketplace.


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