chapter  8
Audio and Video for Your Web Site
Pages 16

AUDIO FILES ON THE INTERNET Most audio files used by consumers for portable devices and Internet delivery are compressed. Compression is a means for reducing file size through discarding much of the duplicated data in the audio file. Consider the way “ditto” marks are used with text, and you get a basic analogy. The creation of the MP3 compression format for audio opened up the possibility for the first time of transferring music over the Internet. MP3 stands for MPEG (Motion Pictures Expert Group) Audio Layer III, and it is a standard for audio compression that makes any music file smaller with little loss of sound quality (although that’s debatable). Without this compression technique, one second of CD quality sound requires 1.4 million bits of data, so the average song in WAV format is extremely large, averaging around 50MB in file size. WAV is short for Waveform audio format, a Microsoft and IBM audio file format standard for storing audio on PCs. With MP3 compression, the file becomes one-twelfth its original size, at about 3 to 4 megabytes, depending on the bitrate.