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Archive for the ‘History of Video’ Category
Wednesday, November 30th, 2011
Have you ever considered that it’s the concept of persistence of vision that makes video possible–the most basic building block of all? “Persistence of vision” is caused by the brain holding an image even after that image has been removed from sight. The phenomenon has been around forever: imagine cavemen waving a burning stick in the darkness and seeing the trail of light behind it. But the concept of persistence of vision led to some of the first optical illusions as well.
In video terms, persistence of vision is what makes video technology work. In the 1800s, it was discovered that a light that flickers quickly enough appears to be continuous to the human eye. How quickly does it have to flicker? That measure is termed the “fusion frequency,” and it usually depends on how well-lit a room is. At low light, the flicker only needs to occur 50 times per second (50 Hz) in order for the image to appear continuous; this is the frequency used in movie theaters and in European televisions (where some people do notice it). American TVs use 60 Hz, which is a better figure for well-lit living rooms, and computer screens use 72 Hz or higher to minimize eyestrain.
 In the 1820s, revolving-picture toys were invented that used the concept of persistence of vision, and are the earliest precursors to modern video technology. These toys were included the fancifully-named zoetrope, fantascope, and phenakistiscope. In creating these toys, inventors learned that if a stream of pictures is too continuous, the eye only sees blurry motion. Each image must appear just long enough for the brain to process it, in order for persistence of vision to work correctly.
Most of these toys featured a slit through which the image was briefly viewable before revolving. Even today, movie projectors still use this same technology–a slit or shutter–to show each frame of a movie, one at a time. A diagram of a zoetrope and how it operates is shown above right.
Wednesday, November 16th, 2011
Yes, you read that right. The death of the compact disc, or CD, is widely anticipated to happen in 2012.
 According to a few websites (primarily the Side-Line.com music magazine), the major recording labels plan to discontinue releasing albums on CD by the end of 2012. Music will thereafter be released via downloading and streaming platforms, such as iTunes and other services. Some CDs will still be introduced, but they will be of the limited and special edition variety, and distributed mostly through Amazon (currently the world’s largest CD retailer).
This news first broke a few weeks ago, but Side-Line.com couldn’t get official comments from EMI, Universal, or Sony on the story. Since then, they have received tips from informants associated with multiple labels who confirm that 2012 is indeed the planned CD end-date. (Nothing has been officially announced or confirmed.)
Granted, this news is not surprising. The CD format has been struggling to hold on for over a decade, beginning with the fight against Napster in the late 1990s.
The simple truth is that CDs cost money. Beyond the obvious manufacturing and printing concerns, there are also the issues of physical storage space for retailers and the money that recording labels pay whenever a CD is returned due to lack of sales. By comparison, releasing music digitally eliminates all stock and distribution issues, allowing the label to focus simply on the music and its marketing. But this change will spell the end for most physical music stores–especially ones that only sell CDs.
What impact does this impending change have for DVD releases? One big difference is that videos still have a strong physical presence. While DVD itself is a declining format, Blu-Ray is improving slowly each year. And while video streaming is growing as well, the physical size of video files mean that they can’t be downloaded nearly as easily as a single MP3 (which is usually just a few MBs). Plus, home videos still require a physical medium for the easiest viewing and archiving security. Music is simply an easier format to adapt to the purely digital realm than video. But it’s a possibility that when CDs go the way of the dodo, DVDs may someday follow.
Saturday, November 20th, 2010
The World Wide Web and DVD might seem to have nothing to do with each other…except when you consider the fact that both technologies became very popular around the same time: the late 1990s. And in fact, the Internet had a lot to do with why the DVD format became the fastest-adopted technology ever.
Before the Internet, it was hard to get your opinion out there, unless you printed your own ‘zine or newsletter. But by the late 1990s–right around the time DVDs were first released–it was becoming easier and easier to start your own website. (This webmaster used Adobe PageMill to create her first website in 1998!) And several early adopters of DVD did just that, starting such sites as the DVD Resource Page, the Digital Bits, the DVD Journal, and DVDFile.
These websites offered far more than just movie reviews. They reviewed DVD releases in depth, offering information about picture quality, special features, and overall value, thus providing a valuable resource that kept customers informed and the studios honest. These websites were updated multiple times each day, so the information never got stale.
Thanks to these sites, studios were forced to re-release DVDs that were criticized for noisy conversions or lackluster extras. For better or for worse, the high standards set by these websites contributed to some movies not being released for many years (including such titles as King Kong and The African Queen). They also managed to take down stupid consumer-unfriendly technologies such as Circuit City’s DIVX.
As a result, the format was strengthened and became consumer-proof. After a year or two, the general public understood that DVDs were, frankly, awesome. There was no argument not to switch from VHS, no well-known drawbacks that people kept hearing about. DVDs offered pristine video quality, widescreen viewing (often for the first time for many movies), a user-friendly menu structure, and a virtually indestructible CD-like disc with no moving parts to break. It was a logical purchase for just about everyone–especially as DVD and player prices dropped further and further down.
So did the web affect DVD? You bet, and we have these vanguard websites to thank for its success. Some of the aforementioned websites are still in operation today, and we encourage you to visit them for DVD and Blu-Ray news.
http://www.thedigitalbits.com/
http://www.dvdfile.com/
http://www.dvdtalk.com/
Monday, November 8th, 2010
In the third and final part of our mini-series on the basics of audio history, things change dramatically. Prior to the 1980s, all audio was analog–either comprised of electrical or magnetic recording. But when the CD was introduced, that all changed. We are still in the midst of the digital revolution that started back then.
 Philips–the company that originally released the familiar 1/8″ audiotape format–and Sony introduced “compact disc digital audio” in 1982. The format was colloquially called the CD. The first album released on CD was Billy Joel’s 52nd Street (pictured at right).
Quick tech speak: digital audio recording, which is how a CD functions, is based on the concept of sampling. Sampling is the process of converting electrical signal levels that are measured over 44,000 times per second into discrete numbers represented by binary digits of zero and one, which are then stored as pulses. (Whew!) This is also called “pulse code modulation” technology, or PCM, and it was originally invented in 1937. PCM is still used by most digital audio, including CD, DAT, laserdisc, and DVD (which uses AC-3, or Dolby Digital audio, as well).
The advantages of digital sound are myriad, and hold true for both the CD as well as the DVD. Digital sound on CD and DVD offers:
– A wide range of frequencies (covering the range of human hearing from 20 to 20,000 Hz)
– A wide dynamic range (very soft to very loud sounds can be played with little noise)
– No quality loss when dubbing
– Longer playing time than tapes or LPs
– Smaller, thinner media size than tapes or LPs
– Instantaneous access to a given song or track
– No wear from playback or access
– More resistant to dust, scratches, and other damage, particular when compared to records
In 1988, CD sales passed LP sales, for many of the above reasons.
Of course, CDs and DVD share the same problem: lack of easy recording. Both discs can be written to (in the CD-R, DVD-R, and related formats) but the process is definitely not as easy as audiotape or videotape recording. Other recordable audio formats, such as DAT or MiniDisc, have died due to high cost, consumer disinterest, and Hollywood’s resistance to digital copying.
Today, audio is still digital, although it is purchased more in MP3 format than as CDs. Is this the way video consumption will go as well? Stay tuned!
Saturday, November 6th, 2010
In the second part of our series examining the history of audio, we’re going to look at the development of magnetic recording technology and audiotapes. This technology was an essential immediate forebear to the introduction of video tape.
Magnetic recording was actually invented in the 1890s, but was not introduced officially until the 1940s. In magnetic recording, polyester tape holds a thin coating of magnetic particles, which are converted to sound when the tape passes over playback heads. Magnetic recording is an improvement over electrical recording, since it makes the recording process much simpler (the same head can be used for both recording and playback).
Around the same time, stereo sound was introduced as well. Prior to the mid-1950s, all sound recording was in mono (originating from a single-point source). Stereo systems incorporated a second channel of sound, which gave the recording greater realism. Stereo tape systems were developed in 1956, with stereo record players following in 1958.
 The first 1/8″ audio cassettes were introduced in 1963 by Philips. (See image at right; the tape was even “made in Austria”!) The format was originally intended to be used for business dictation, but it soon became popular for music as well.
Pre-recorded audio tapes were released in 1966, and slowly but surely began to compete with traditional LPs. The 8-track tape also enjoyed a measure of success, particularly in cars. But the 1/8″ format grew more and more in popularity, and became solidified in consumer culture when Sony released its Walkman personal audio player in 1979.
An important development alongside magnetic audio tape was the development of Dolby noise reduction. The technique appeared in 1969, and its ability to reduce tape hiss was strongly responsible for the success of audiotapes. Today, the same theories form the basis of the Dolby Digital surround-sound tool used in DVDs.
In 1982, audio tape sales passed record sales for the first time. But a new format was on the horizon…one that would lead directly to the development of the DVD. Check back soon for a recap of the CD!
Wednesday, November 3rd, 2010
From time to time, we’re going to take a look at the history of video on this blog–always in as easy and brief a fashion as possible! Video has passed through many permutations over the years, and it’s instructive (and interesting) to look at the development of the field.
However, while the moving image and film are important to the development of video, its roots lie with the history of audio technology in many ways. Today, we’re going to briefly run through the first important milestones in audio development.
 The year 1877 marks the birth of audio. That was when Thomas Edison recorded and played “Mary had a little lamb” on a strip of tinfoil. Ten years later, 12″ 78-rpm gramophone disks, each containing 4 1/2 minutes of music, were all the rage–only to be replaced by the Victrola in 1901. At this time, the method of recording was acoustical, meaning that sound vibrations were converted to grooves on a wax disc.
Radio finally came along after World War I, with the first commercial broadcast in 1920. At the same time, acoustical recording was replaced by electrical recording. This meant that sound vibrations were converted to electrical impulses, which then drove an electromechanical cutting head that cut the grooves on a record.
The LP (long-play) record was introduced in 1948 by Columbia Records. A 12″ LP could hold up to a half-hour of music at 33 1/3 rpm–much more than just a few minutes–due to the new microgroove technology. Less than a year later, RCA released a 7″ record that turned at 45 rpm and played about 8 minutes of music. Both formats quickly replaced the old 78s, and despite the growth of tapes and CDs, 33s and 45s remain popular with audio fans even today.
In our next post, magnetic recordings and audiotapes come along…so check back in a few days!
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