Sound and pictures: all the rage: 2

By Chris Ricci

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There are numerous audio and video file formats. Audio files on a computer typically use a format called WAV, just as a word document is a DOC. They all compete for market share and top-brand recognition. The leaders of the pack are MP3 for audio; created by the Fraunhofer Society back in 1991, and WM/F/P/V (Windows Media format/player/video). Video formats are led by MPEG (MPG) and Apple Corporation’s QuickTime which share the top spots in video players. Had it not been for the PC/MAC separation, MPG would have most likely prevailed.

The process of encoding audio and video data has evolved in many competing formats, as used by just as many vendors. This is because there are no MP3 encoding standards. There are only guidelines. This confuses consumers, and that’s not good. Which standard to use, what features does each format offer, etc? Bottom line, there are good, better and best formats.

MP3 encoding quality can be usually measured in bit-rate sampling. The higher the bit rate, the more original data is preserved from the original recording. Commonly used rates are 64, 96, 128, 192, 256 and 320 kbits. Audiophiles and professional audio enthusiasts often use 320 kbit. To further complicate matters, MP4 has become popular. This format is both audio- and video-compatible, and acts as a container for multimedia data. Apple is using this format for M4A (essentially, MP4 audio).

Sampling rates are another factor in recording quality. To keep things simple, though, we seem to have adopted the sampling rate used on CDs, which is 44.1KHz. A one-minute CD clip would take about four minutes to download from your high-speed Internet connection, compared to about 20 seconds for the same clip in MP3 format.