Video Codecs Easily Explained

Cnet has a very easy to read article explaining what video codecs are, how they are used, and what and why there are so many competing codecs. Here’s what you need to know:

What is a codec?

Video codecs (a contraction of "coder-decoders") are important because they determine what quality of video can be squeezed into a given amount of digital storage space, or can be sent over a DSL or cable television line. The codec is an essential part of a DVD. … A technology for squeezing audio or video into smaller packages for easier storage or transmission.

Basically video takes up a lot of ‘space’ so we compress it and shrink it down and then we need to decompress the video before it hits your screen so you see the video in full screen and full quality. That’s what the codec does, handling this compression/decompression.

Here’s the three major codecs you will hear about:

MPEG-2 A set of multimedia technologies finalized by the MPEG group in 1994. Typically used as shorthand for the video codec, finalized in 1994, that is used today on DVDs, cable networks and in many other places.

MPEG-4 AVC A later video standard finalized by the MPEG group. Also known as H.264 or Advanced Video Coding.

VC-1 The version of Microsoft's Windows Media 9 video codec submitted to industry standards bodies for use on DVDs and elsewhere. Was temporarily known as VC-9.

So Apple supports the MPEG-4 or H.264 and Microsoft supports the VC-1 codec and Sony still wants to use the MPEG-2 codec for future Blu-Ray high-def DVD’s. The newer video codes are supposed to be faster and offer more compression (less disk space) but some say the MPEG-2 can still offer the same quality but time will tell when high-def DVD finally hits the streets.