You, the new recruit to the video industry, are the future. It is you that will be the first to experience the massive explosion in new technology that is now beginning. Undoubtedly the future is digital. Digital technology should be viewed as two separate, and distinctly different, areas.
One area is the digital revolution in tiny chips that are, in effect, small computers. These already control image stabilization, extended zoom, exposure and light balance in modern cameras.
Bigger chips control video and sound capture, allowing the pictures and sounds to be manipulated within the digital domain of the computer. Digital video effects can be created by programmes that are specifically written to be incorporated in vision mixers and are also found within modules of non-linear editing programmes. Buying ‘video capture cards’ or ‘non-linear editing programmes’ often means buying a small computer contained within a plug-in card which is designed to be used in conjunction with a bigger computer which has storage space and an operating system. This is why these devices are known as ‘add ons’ or ‘upgrades’.
The second area is that of digital recording. There is no mystery or complication to digital recording. If you remember the basics the worst thing is that you will have to learn a few more technical terms. The basic fact is that we have pictures we can see and sounds we can hear. These need to be stored somehow so that we can play them back when we want to. This book explained magnetic recording in a very simple way when we looked at editing, whereby these pictures and sounds are transferred into electrical signals which represent the pictures and sounds as analogue copies. These electrical signals are then transferred into magnetic signals, again analogue, which are stored onto a tape-based magnetizable material in the form of a handy-sized cassette.
Digital recording still starts with pictures we can see and sounds we can hear, they are still transferred into electrical signals but these signals are made up of a series of numbers, made up of noughts and ones, which represent the signal. Each nought or one is known as a bit because it is represented by BInary digiTS, the more bits used to represent a number the better. The minimum number of bits to represent one number is eight, eight bits are known as a byte. This will lead you to understand how we get 8-bit systems and that 16-bit systems are better (more bits per number) and you will probably have heard of 24-bit and 32-bit systems.
These bytes are stored as binary numbers by converting them to magnetic signals and recording them onto tape. The problem with digital video has never been with digital tape based systems. A digital edit suite, with tape based machines, works in exactly the same way as has been described earlier under ‘editing’. Digital recording gives better quality pictures and sound and does not suffer from generation loss when copied.
The problem began when ‘tapeless’ systems were required. The massive number of bytes that needed to be stored meant that large amounts of memory were needed and memory costs money. The solution is to use some form of data reduction, known as video compression. The greater the compression, the greater the loss of quality. As an example, to compress six or seven minutes to the equivalent of S-VHS quality would require a storage space of around one gigabyte. The cost of disc drives is falling rapidly as is the ability to produce hard discs with massive storage space.
The next stage is to produce disc-based camcorders which will do away with the need to transfer the tape-based digital images to a computer memory. They do already exist but the need for storage space means that bigger capacity discs are needed than are presently available. The very forefront of technology now (end of 1998) is the Digital Versatile Disc (DVD), at the moment these are playback only but with a capacity of nearly 20 gigabytes and a better compression system than the current ‘standard’ this will soon become the next generation of storage systems.
It is a pity that the multi-format systems of analogue recording have been carried into the digital domain. Different manufacturers are leap-frogging over each other to provide the latest technology. The future will finally have arrived when all systems are equal and all interchangeable. It is strange that while it has been possible to buy an audio cassette recorder for the last thirty years that will operate happily anywhere in the world, with total interchangeability, the manufacturers have not taken the opportunity of the digital revolution to produce a compatible system.