An Introduction to Digital Media

History of Music and Sound

It might surprise you to know that the digital medium can be traced back to the creation of the number "0" by the Babylonians two thousand years before the birth of Jesus. However, since most of you (us included) would rather play Xbox than visit a museum of technology, we'll skip about two millennia.

Advertiser Links for H.261

Instead, we can begin our introduction to the history of digital media in the 1970s -- the decade of Farrah Fawcett and disco. Let's face it: if we're talking about video and audio, there were a lot of people out there who wanted to see Farrah and listen to disco (although we're not sure why).

Digital Audio

Digital audio began in that "bell bottom" decade when the Japanese company Denon began commercially recording classical and jazz melodies. Although it was the Japanese who first dabbled in producing digital music for the mainstream, Americans took over from there.

Towards the end of the 1970s, digital-music recordings became popular. However, it took until 1978 before Ry Cooder's "Bop Till You Drop" received any fanfare. Although most people won't recognize Cooder's name, Stevie Wonder embraced the digital technology when he released his 1979 album, "Journey through the Secret Life of Plants." Strange name or not, the song got things rolling for digital audio, and, although there were notable critics (such as the Beatles), the trend grew, along with a number of other electronics applications in the 1980s.

Digital media began because
people wanted to hear disco….

In recent decades, digital audio has become increasingly popular since the advent of the Internet. From WAV to the MP3 generation, music has being streamed through a number of different audio formats, with an equally staggering variety of qualities. Some digital audio sound better, some are easier to download, and others offer real sound techies the ability to manipulate every sound signature.

Digital Video

Although cave drawings are probably the earliest recorded images, no one really links them with today's modern digital video formats or the players that integrate them. Therefore, for sanity's sake, we'll simply begin with the modern video camera, which may capture images in two different formats: interlaced and progressive scan. Interlaced video isn't much different than the name suggests: it features video through lines, where the odd-numbered bars are scanned before the even numbers. This whole process is essentially what you're viewing when using interlaced video. Furthermore, interlaced video has remained popular for a very long time.

Progressive scan recognizes each captured frame as a unique image. This means that the interlaced variety – which only scans every other line – is twice as efficient. However, progressive scan camcorders are more desirable to many filmmakers because they record frames progressively, often leading to a more vivid image.

Jump ahead to digital video and the Internet, and you'll find that moving images don't quite have the rich history as that associated with digital audio. Since our main concern here is digital video and its role in shaping the Internet, our story begins with H.261, which was introduced in 1990. H.261 was the first practical video coding standard, which means that all of the MPEG standards have been based on its initial design. Without H.261, you wouldn't have the mega popular MP4 file format.

…and view Farrah Fawcett

However, it's hard to classify H.261 as a codec, because that term essentially refers to standards that both compress and decompressa content. H.261 is designed for only the latter, meaning that it was designed for exclusively expanding your video files. H.261 left the encoding challenge up to the designers, but did provide them with an effective framework (including constraints).

Video has come just as far as sound in compression technology. Let's face it, there's more of a challenge to reducing the file that plays both music AND video, rather than that singular-minded song. Nowadays, you can enjoy movies pretty much anywhere by downloading the formats onto your iPod video or other multimedia devices. Additionally, storage devices that once only offered sound, like compact discs, now double as video tools. Many of today's bands include video on the same disc, and you can view these by popping them into your average DVD or CD-ROM player.