When viewing video files on a computer, the user usually does not encounter any problems. But sometimes the movie can play without sound, or even refuse to start at all. In this case, a message will appear stating that the player cannot play this type of file. Such a failure is due to the lack of the necessary decoder on the computer.
Media files are usually large, sometimes reaching several gigabytes. It is very inconvenient to use such files - in particular, they are difficult to transfer over the Internet. This is especially true when sending a movie, downloading it can take many hours. To make the film more compact, it is encoded, that is, compressed according to a certain algorithm. The file is significantly reduced in size, but needs to be decoded again in order to play it. It is this task that decoders undertake, unpacking the compressed file and transmitting the restored recording for playback.
The decoder is a small program, it can be separate or included in the player. On DVD-players, made as a separate device, the required set of decoders is embedded in the memory and cannot be changed. The situation is different with computers; you can easily change the set of decoders on them. As a rule, usually the user deals not with pure decoders, but with codecs - programs that can both encode and decode a multimedia file. As you might guess, the name "codec" is made up of the first letters of the words "encoding" and decoding ".
By itself, the codec usually cannot play the file, its task is only to encode and decode. Therefore, the codecs are included in the software of the players. For example, popular players such as KMPlayer, Light Alloy or Media Player Classic include a large number of audio and video codecs. Thanks to their presence, it becomes possible to simply insert a DVD-disc into the drive and watch movies without thinking about their encoding.
You can see what codecs are installed on your computer. To do this, right-click the "My Computer" icon on the desktop, select "Properties". Option: open "Start" - "Control Panel" - "System". Next, go to the "Hardware" tab, click the "Device Manager" button. In the section "Sound, video and game devices" double-click the line "Video codecs" and in the window that opens, select "Properties". You will see a list of video codecs installed on your computer.
