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BTC640/Video

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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.
 
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. The transmission channels are usually separate though.
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.
channel conversion=== RF channels === * Coaxial cable (like cable TV) actually transmits radio signals over a wire, which is why it's heavily shielded. It can be used for both analog (like traditional cableTV) and digital (like high-speed internet) signals, often at the same time.* Broadcast TV uses some of the available RF spectrum to broadcast video signals as far as they will go. This used to be completely analog transmissions, but more recently digital transmissions started beeing used. This is a heavily regulated distribution channel, you cannot simply set up your own.  = Links = * http://en.wikipedia.org/wiki/RCA_connector* http://en.wikipedia.org/wiki/TRS_connector* http://en.wikipedia.org/wiki/Component_video* http://en.wikipedia.org/wiki/S-Video* http://en.wikipedia.org/wiki/Composite_video* http://en.wikipedia.org/wiki/VGA_connector* http://en.wikipedia.org/wiki/Digital_Visual_Interface* http://en.wikipedia.org/wiki/HDMI* http://en.wikipedia.org/wiki/Uncompressed_video* http://en.wikipedia.org/wiki/Coaxial_cable* http://en.wikipedia.org/wiki/Tv_antenna* http://en.wikipedia.org/wiki/Broadcast_television* http://en.wikipedia.org/wiki/Digital_terrestrial_television* http://en.wikipedia.org/wiki/High-definition_television* http://en.wikipedia.org/wiki/Comparison_of_container_formats* http://en.wikipedia.org/wiki/Container_format_%28digital%29
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