Dolby Digital (5.1)
Dolby Digital, also referred to as AC3, is a digital audio format with which up to six separate audio channels can be transmitted. On most current DVDs, the audio is stored in "Dolby Digital 5.1" format; the "5" in the name "5.1" stands for the three front and two rear sur- round sound channels, the "1" stands for the subwoofer channel.
DTS
DTS is the abbreviation for "Digital Theatre System" and refers to one of the most common surround sound formats for DVDs. As with Dolby Digital 5.1, DTS uses three front and two rear surround sound channels as well as a subwoofer channel.
What are PAL, NTSC and SECAM?
PAL
PAL is the abbreviation for "Phase Alternation Line". PAL is the typical and most common colour television standard in Central and Western Europe (exception:
France, see "SECAM").
NTSC
NTSC is the abbreviation for "National Television System Committee". NTSC is a colour television stan- dard that is used primarily in the USA and Japan.
SECAM
SECAM is the abbreviation for the French "système en couleur avec mémoire". SECAM is currently the typi- cal and most common colour television standard in France and many Eastern European countries.
Audio CDs
Audio CDs contain only audio data; they are also avai- lable in the sizes 8 cm and 12 cm (diameter). The playback time for the audio data stored on CDs is 20 minutes (8 cm size) or 74 minutes (12 cm size). Audio data is stored on audio CDs in the CDA format.
MP3
MP3 refers to a method or format for compression of audio files developed by the Fraunhofer Institute. Works of music compressed in MP3 format are only a fraction of their original size, making it possible to store significantly more music on
WMA
WMA ("Windows® Media Audio“) is a file format for audio files developed by Microsoft®.
JPEG
JPEG ("Joint Photographics Expert Group") refers to a widely used graphics format developed by the organi- sation of the same name, with which colour and gray scale image data are compressed.
DivX
DivX® is an encoding format for video and multimedia data developed by the company DivXNetworks®, Inc.
MPEG
MPEG ("Moving Picture Experts Group") refers to a video compression standard.
What are folders?
In contrast to → audio CDs, the titles on a
→JPEG files can be stored in folders, for example, to organise titles from various genres.
For instance, the structure of an MP3 CD may appear as shown below if the MP3 files were saved in folders.
Fig. 25 Possible folder structure for an MP3 CD
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