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Because the technology is quite complex we will only get an overview of video in this course, without going into too much detail, but you need to know some basics at least.
== Codecs and Containers ==
Video is encoded and decoded using a codec. The format is a digital representation of the data (like PNG, WAV, BMP), and the codec is a program following rules for creating and displaying it (like libpng).
Video is rarely used without audio, but the two are separate technologies that are combined into one by placing them into the same container and synchronising their playback. This is the main reason that a container is not the same as a codec.
Examples of containers:
* AVI
* MPEG
* Matroska (mkv)
* Quicktime (mov)
* 3GP
* Flash (flv)
Each of these containers contains video in one of a few formats, for example:
* MPEG-1
* MPEG-2
* MPEG-4
* H.263
* H.264
* Theora
as well as audio in one format or another.
The decision which container and format to use is usually dictated by the tools available, the distribution channel, and the size/quality of the result.
== Channels and Interfaces ==
There are two big categories here: analog and digital. With video the differences between the two are similar to the differences between analog and digital audio, though unlike analog audio - analog video is lossy.
Here are the most popular channels and interfaces for video:
* HDMI: an interface that includes digital video, digital audio, CEC, and even ethernet. Mini HDMI and micro HDMI are also becoming popular, used on smaller devices such as smartphones.