Glossary

Bit rate

Indicates the data amount per second. The rate is reflected in bps (bit per second).

64 kbps means 64000 bits of information per second. If the bit rate is large, that means a large amount of information is used to play music. Comparing music of the same format (e,g., ATRAC3plus), 64 kbps data offers better sound quality than 48 kbps data. However, audio files in formats such as MP3 have different encoding methods, and thus sound quality cannot be determined by simply comparing the bit rate.

MP3

MP3, which stands for MPEG-1 Audio Layer-3, is a format standard for music file compression. It was codified by the Motion Picture Experts Group, a working group of ISO (International Organization for Standardization).

It compresses audio CD data to approximately one tenth its original size. Because the MP3 encoding algorithm has been made publicly available, there are various encoders and decoders that are compliant with this standard.

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