DVD decoder – Why Do you Need One?

by eddy

The DVD decoder is one of the most popular types of media sold today. They hold feature length motion pictures, videos, audio and countless other types of media, such as software and data. DVDs can be played on standalone DVD players, as well as on computers since most computers have a DVD decoder drive. If a DVD includes media such as a feature length motion picture, this media has been encoded and may have also been compressed. In order for this type of DVD to be played on a computer’s DVD decoder drive, the data on the DVD must first be decoded; this is done with help of computer software. It should be noted that there are many types of DVD formats, hence several types of encoder programs are available to make a DVD suitable for all computers.
DVDs encode data in a variety of ways. For instance, Dolby Digital data requires a Dolby Digital DVD decoder. The same is true for DTS (Digital Theatre System). These are both audio data that require decoding, but many video images stored on a DVD also require decoding, for instance, the MPEG-2 (this is the most popular video format for DVDs). It should be noted, that in order to play a standard DVD, just a DVD player is not enough. Software that decodes the images is also mandatory. Without this, the images cannot be decoded and the data will not be fully functional. Here is where a DVD Decoder becomes essential.

DVDs work on two standards; NTSC and PAL, each of these standards have different formats. For instance, NTSC requires 30 frames per second in a 60 field sequence. For PAL, 50 fields per second are required; however movie images are filmed at 24 images per second. For a film to meet either standard, encoding occurs. Encoding also allows the compression of video images- this is the process of making a data file smaller in storage size. Usually static data is put aside to allow compression to take place. For instance, a 30 minute talk show in which the background is static and never changes can be compressed more than a 30 minute video of a race car moving quickly around a track can be compressed.
The DVD Decoding Process:
DVD decoders perform three primary functions. First, all DVDs that are sold by the major movie studios include copy protection to make it difficult for anyone to make copies of the DVD’s data. The copy protection is called CSS and in order to view the file, a DVD decoder is necessary to unlock the copy protection. Secondly, DVD decoders decode the MPEG-2 format, recreating the data so that the original images can be viewed. And thirdly, the decoder makes it possible for these images to be played through a viewing program which is installed on the PC.

To play a standard DVD on a computer, a DVD player, commonly referred to as a DVD drive, and the decoding software are necessary. Decoding software is not free. Since the MPEG-2 is a licensed format, licensing and royalties must be paid to the patent holders in order to decode the DVD and view the data on it. Even if a DVD drive is already present, software to decode the format is still necessary. This is the reason why there are no free alternatives.
While there is no standalone DVD encoding software program that is free, a free player can be found, that has the ability to decode MPEG-2 files. The player is called VLC and can play on practically all types of computer operating systems. Some of the formats that VLC can decode and play within its media player program are MPEG-1, MPEG-2, MPEG-4, DivX, MP3and OGG.
The VLC media player does not need a separate decoder to play DVDs, so it is the best free solution for using a computer DVD player with no DVD decoder software. While it is possible to play DVDs with a VLC player, other media players such as Windows Media Player do require an encoder to play DVDs. For people who would like to play DVDs on their computer, some popular choices include Win DVD and Interview’s DVDXPack.

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