Video file formats

Understanding video file formats

With the rising popularity of video on the web and sites like YouTube, there is an increased need to understand the different types of video file format and what they do.

Each format has its advantages and limitations, but the major issue in the world of video is compatibility. Some media players such as RealPlayer have made it easy for us by playing virtually all types of video files, but some standards, or codecs, are tied to particular applications and devices.

Much of the video content we watch on the web is ‘streamed’.

This tends to be the best way of watching short clips quickly, though if your internet connection is slow the video can stop and start, because the data isn’t being transferred quickly enough. For longer videos, it is generally better to download the file first before playing it to ensure smooth viewing.

Getting DVDs to run on your PC can occasionally be problematic. Windows Media Player, for example, needs to install a decoder add-on to turn it into a fully functional DVD player. We’ll look at how to do this and explain some of the major file formats in detail here.

MPEG

Most of you will have heard of MPEGs. The acronym stands for the Motion Pictures Expert Group and the first version of this format – MPEG-1 – was created as an audio and video compression standard used for Video CDs. MPEG-2 refers to standards for audio, video and the transport of broadcast television over digital and satellite TV networks and was also the file format of choice for the first DVDs.

MPEG-4 is a group of standards that include support for Digital Rights Management (DRM) technology, which lets the owners of video content stop people from making unauthorised copies of it. MPEG-3 was a short-lived standard used for high-definition video but it was subsequently killed off when MPEG-2 was found to be sufficient for HD.

H.264

Included in the gamut of standards covered by MPEG-4 is a format called H.264, which is also referred to as Advanced Video Coding. This is a format that can deal with high-definition content such as that on HD-DVDs or Blu-ray discs.

This particular format was created in 2003 to produce high-quality video at lower bit-rates, resulting in smaller file sizes. Videos downloaded from the iTunes store use the H.264 format and it has recently become the default standard for YouTube content.