It is a digital world and no doubt about it. But digital video is possible only with compression. Television, for example is extremely information rich. Digital television transmission is at 270 mega bits per second which is huge amount of data. This kind of data requires cabling and satellite communication would not be realizable. It requires very large bandwidth and formidable storage space . Compression is the only alternative available. Digital compression systems take the advantage of the inherent contents of television video i.e. repetition and redundancy, both within and between picture frames.



DV, digital Video and MPEG are the key compression technologies, which have emerged for video and television. DV compression being intra frame is the most suitable for video recording and post production. MPEG compression being inter frame makes use of repetition and redundancy contained in video. It has high compression ratios which are suitable for storage and transmission.

Digital video, DV has led to cost effective video tape recording, non linear post production work stations, video servers and multi-channel satellite TV transmission. It is possible to transmit more than six TV channels simultaneously over a medium which would otherwise support only one analog channel.

The latest entrant to the DV community has been HDTV or high definition TV and Digital cinema. With digital or e-cinema, new avenues have opened for cinema broadcasting via satellite. Digital cinema delivery is far cheaper than film print cost. The hard, cumbersome and time consuming job of distributing heavy canisters of film may soon be a relic of the past. This would likely be replaced by fast, high bandwidth satellite transmission.

Video storage systems

Moore's law in the development of electronics has been true in the case of disc drives. The capacity of disc drives has doubled every two years and its cost has fallen to half. We are therefore witness to higher capacity hard discs available at cheaper cost. Non-linear editing in a networked environment , storage of video assets on servers ,automation in news and transmission have been implement in a large scale multi channel environment . Video servers are the only viable option for multi-channel broadcasting where playing repetitive program material such as commercial spots, promos and films for video on demand services.

Moore's law in the development of electronics has been true in the case of disc drives. The capacity of disc drives has doubled every two years and its cost has fallen to half. We are therefore witness to higher capacity hard discs available at cheaper cost. Non-linear editing in a networked environment , storage of video assets on servers ,automation in news and transmission have been implement in a large scale multi channel environment . Video servers are the only viable option for multi-channel broadcasting where playing repetitive program material such as commercial spots, promos and films for video on demand services.

Digital Camcorders with hard disc drives are also available, but for initial acquisition of live video analog systems and tapes are still the preferred medium for its cost, reliability and convenience. Moreover professionals are used to existing analog systems and are slow in absorbing the devices of the new age. Soon we will find analog systems totally eclipsed by digital ones.

Copyright (c) 2007 Dean Barnard