Glossary (continued)“Check-In /Check-Out”

Check-Out is to transfer music files managed on a personal computer by an OpenMG-compliant software to a portable player (such as Memory Stick Walkman). Returning the Checked-Out music files back to that computer is to Check-In. (You cannot move a Checked-Out audio data to another computer.)

You can also Check-Out a music file, Check it back In, and then Check it Out again.

The SDMI rules provide that up to four copies of a music file can be created unless a special condition for usage is set. Thus, unless a special restriction exists while one copy is saved in the computer, the other three can be Checked-Out to the Portable Players.

MP3

Abbreviation for MPEG-1 Audio Layer3. A standard for audio data compression determined by the Motion Picture Experts Group, which is an ISO (International Organization for Standardization) working group.

It enables compression of audio data to about 1/10 of the data size of a standard compact disc. Since the MP3 encoding algorithm is disclosed, there are various encoders/decoders compliant with this standard, including freeware that is available for no charge. Thus, the MP3 standard is widely used in the computer field.

Bit rate

Quantity, per second, of information. The unit is bps (bit per second). You can choose from 132kbps/105kbps/66kbps when recording a compact disc or converting an MP3/WAV file to an ATRAC3 file. For example, 105kbps means there are 105000 bits of information per second being transferred. Bigger the number, larger is the information. When comparing audio files of the same format, you can enjoy a better sound quality when recorded at 132kbps than at 105kbps, also better at 103kbps than at 66kbps. (Audio files cannot be compared if of different format)

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