Videomaker by John Devcic MPEG-2, DivX, AVCHD: These are just a few of the confusing acronyms of digital video. Let's clear the air a bit
To understand Digital Video Architecture, you need to start at the beginning. The beginning in this case is known as Video Compression. That is the start of this article; after that, we will get into the most common formats in use today. In order to make digital video's use widespread, there had to be a way to reduce the amounts of data that needed to be stored and transmitted. This reduction in the amount of storage is a direct result of the advances made possible by video compression. The advances in video compression have single-handedly led to the widespread use of video to the desktop and to hundreds of channels in your home. To boil it down to its most simplistic level, compression is performed when an inputted video is analyzed and the information that is indiscernible to the viewer is dropped. Each event is given a code - the most commonly occurring events are given fewer bits and the rarer events will have more bits. These steps are usually known as signal analysis, quantization and variable length encoding. There are 4 major ways to compress video. Discrete cosine transform (DCT)
, vector quantization (VQ)
, fractal compression (FC)
and discrete wavelet transform (DWT)
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