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Format Terminology

Format Terminology

Once, there was VHS and there was... VHS. Now with AVCHD, DVCAM, Mini DV and more, recording choices are mind boggling. Let's decipher the alphabet soup. It used to be that home entertainment formats changed very slowly. Phonograph records spun merrily at 78rpm...

Once, there was VHS and there was... VHS. Now with AVCHD, DVCAM, Mini DV and more, recording choices are mind boggling. Let's decipher the alphabet soup.

It used to be that home entertainment formats changed very slowly. Phonograph records spun merrily at 78rpm for half a century before being replaced by the 33-1/3 "long play," which itself reigned nearly unchallenged by all but cassette tapes before the compact disc came into its day at the end of the 20th century. Video technology has not shared this paucity of formats - their numbers may be positively bewildering. Since the first home video players arrived on the market, the number of different options has been staggering - and confusing.

We're going to take a look at some of the most popular formats from the beginning of the home video era up to the most cutting-edge standards. (Those of you who just stumbled across this in a trunk in your attic in 2041 may begin laughing now.)

Analog Formats

VHS: 240 Scan Lines, Mono or Stereo.

Despite the fact that VHS didn't really hit homes until the 1980s, JVC launched the format in 1976. It battled with Betamax to become the home video standard and eventually won. While it's still widely popular, nearly all movie studios have stopped releasing products on VHS. The format allowed for three speeds: SP (standard play, 2 hours), LP (long play, 4 hours) and SLP (super-long play-also known as EP, or extended play), which recorded six hours of video on a standard T-120 tape. Physically the tape was 1/2-inch wide, but the use of a helical (slanted) recording head allowed the data stripes to be longer. VHS is undoubtedly the most popular legacy format and, with the number of weddings and vacations recorded on VHS in the last twenty-five years, decks will probably remain in people's homes for some time.

Notable variants were VHS-C, which used a smaller cassette, and Super VHS, which had improved audio and video (420 lines of resolution). There was also S-VHS-C, which combined both of the above permutations. None of them caught on widely.

Betamax: 250 Scan Lines, Mono or Stereo

If you find an odd videotape at a yard sale and can't figure out what it is, chances are it's Betamax. Released in 1975 by Sony, the slightly smaller, slightly shorter tape entered into a brutal battle with VHS for the home video market in the 1980s. Key among the factors that caused the eventual demise of Betamax was the initial 1 hour recording time. Home users were willing to forgo Beta's negligibly better video and audio in exchange for being able to watch an entire movie without having to switch tapes in the middle. Sony fought back after the release of VHS by coming up with a longer tape and slower recording/playback speeds, but VHS' lead was too large by then.

Eventually this format was turned to pro use only, and TV stations across the country used fast recording high quality Beta tape and only Beta for more than 2 decades.

Video8/Hi8, 270/400 Lines, Mono or Stereo

Kodak released Video8 in 1984. Users were enjoying their VHS decks, but the size of the tape made camcorders extremely bulky. Kodak's miniature tape was about 20% the size of the clunkier VHS and allowed the creation of extremely portable cameras. Sony produced an upgraded version of Video8 called Hi8 (which stands for High Band) with significantly improved image quality. Hi8 players can play Video8 tapes, but not the other way around.

Digital formats

As the sun set on the 20th century, digital was just coming to consumer video in America. The equipment was changing rapidly, as was the method of distribution. Largely now, video was either transferred by DVD to large, multi-channel home theaters, or, in an interesting turn, watched at rather low resolutions on portable devices.

Digital 8: 500 Lines of Resolution

Digital8 is a highly-improved version of Video8, launched in 1999. It uses the same tapes as Hi8, but it moves the tape at twice the speed. The quality of Digital8 is the same as that of Mini DV, but the decks and camcorders never really took off. Unfortunately, the format is now considered dead by many.

DV and Its Variants

In 1995, Sony announced that it was releasing two cameras that would use digital (rather than analog) video, meaning lossless duplication and 25% more lines of resolution than Hi8, among other things. Other manufacturers like JVC and Panasonic rapidly followed suit. Professional videographers flocked to the new format, and it wasn't uncommon to see a bunch of dinky football-sized cameras mixed in with huge Betacams on the press riser at events. Indie moviemakers even started using them instead of 16mm film (the 2004 Sundance sensation, Open Water, was filmed with Sony DSR-PD150s and DCR-VX2000s). Soon afterwards several "professional" versions of DV appeared, each of which touted improvements on the vanilla versions.

There are three popular versions of the DV standard:

Mini DV: 500 Lines

Mini DV cassettes can store 60 or 90 minutes, depending on which tape speed you use. The very small tape size (65x48x12mm) makes them very popular and easy to transport.

DVCAM: 500 Lines

Sony developed DVCAM, geared towards wedding, corporate and industrial videographers. It uses the same tapes as Mini DV, but the transport moves 33% faster through the camera, allowing for wider data stripes across the tape. Cameras that can record DVCAM can also record and play back in standard DV mode.

DVCPRO: 500 Lines

Panasonic launched DVCPRO for professional television journalists, with price tags that figure accordingly. A DVCPRO editing deck can cost as much as two used cars. DVCPRO uses a different type of tape and is able to give extremely precise edits with linear editing systems. There are two additional variants of DVCPRO: DVCPRO50, which has a bitrate twice as high as DVCPRO, and a high-definition variant called DVCPRO HD or DVPRO100. DVCPRO achieves these features by higher tape transport speeds. DVCPRO50 runs the tape twice as fast as standard DVCPRO and DVCPRO100 runs it four times as fast. Therefore a 66-minute DVCPRO tape will last 16 minutes and 30 seconds in DVCPRO100 mode.

HD Formats

HDV: 720p and 1080i

JVC launched the first HDV camcorder, the GR-HD1, before HDV even had a name or a standards body associated with it. It was the first consumer camcorder that could record 720p video. Sony launched the HDR-FX1 the next year, the first consumer 1080i camcorder. All HDV camcorders record MPEG-2-compressed bitstreams to standard Mini DV tapes; however, the use of HD-grade tape is recommended because HDV bitstreams are much more susceptible to the effects of dropouts on the tapes.

AVCHD: 720p and 1080i

AVCHD represents one of the first video formats released to consumers that does not have a specific type of media associated with it. AVCHD writes MPEG-4 AVC bitstreams to devices such as memory cards, hard drives or optical discs (usually 8cm DVDs). MPEG-4 AVC itself is also an excellent distribution format-read more about it below.

Distribution Formats

The way we watch video has also changed. With digital formats came numerous playback options, from handheld devices to sophisticated large screens. We'll take a look at a few of them and their application. Distribution formats have variable resolutions.

Windows Media

In 1991, Microsoft released the first version of Windows that could play multimedia files. Since then, it has released a player, an encoder and a streaming video server. WMV, first introduced in 1999 with Windows Media Player 7, is a widely-popular proprietary encoding scheme developed to compete with Real. It comes with every copy of the Microsoft Windows operating system and is capable of playing back at high-definition resolutions.

H.264 / MPEG-4 AVC

Developed by the Motion Picture Experts Group (MPEG) as part of the MPEG format, H.264 is commonly referred to as MPEG-4 AVC (Advanced Video Coding). The H.264 reduces the bitrate of its predecessor, MPEG-2 (or H.263) by nearly 50 percent, allowing transmission of higher-definition video over the same bandwidth.

MPEG-2

MPEG-2 is, at the moment, ubiquitous. It's the format used to encode audio and video onto DVD and it's the format that broadcast digital television stations use. It uses a lossy compression algorithm to search for redundancies in images and frames (realizing that one frame of video is usually remarkably similar to the ones immediately before and after it) and discards some of the information. Its predecessor, MPEG-1, is used to create VCDs (video-compact discs) which, while popular in Asia, never broke in the U.S. due to the low playback quality, though many DVD players will play them.

Real

RealVideo was released by RealNetworks in 1997, and was a popular early method of distributing video, especially streaming video, which slowed down wait times by buffering a portion of video and allowing playback and downloading to take place simultaneously, instead of making the viewer wait for the entire video to download before playing. RealVideo files usually end with the extension .rm.

What's Next?

Formats didn't change much in the 1980s and 1990s, but now we have so many choices that it can be hard to figure which is best for your needs. This new millennium is going to enter into its second decade soon, and what's coming down the pike is anyone's guess. Care to comment? Write us about your predictions at editor@videomaker.com and reference this article in the subject line.

Contributing Editor Kyle Cassidy is a visual artist who writes extensively about technology.

Tags:  February 2009
Kyle
Cassidy
Sun, 02/01/2009 - 12:00am