THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
CONTRIBUTORS “AS IS” AND ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
DAMAGE.
Linear PCM
This is an uncompressed PCM (Pulse Code Modulation) signal. Unlike
lossy compression audio sources such as MP3, no audio quality or
dynamic range deteriorates.
MP3 (MPEG Audio Layer-3)
This is an internationally standardized audio data compression scheme,
using the “MPEG-1” video compression standard. It compresses the data
volume to about one eleventh its original size while maintaining sound
quality equivalent to a music CD.
MPEG (Moving Picture Experts Group), MPEG-2, MPEG-4
These are the names for digital compression format standards used for
the encoding of video and audio. Video standards include “MPEG-1
Video”, “MPEG-2 Video”, “MPEG-4 Visual”, “MPEG-4 AVC”. Audio
standards include “MPEG-1 Audio”, “MPEG-2 Audio”, “MPEG-4 AAC”.
WMA (Windows Media Audio)
This is the audio compression technology developed by Microsoft
Corporation.
WMA data can be encoded using Windows Media
®
Player.
To encode WMA files, only use applications authorized by Microsoft
Corporation. If you use an unauthorized application, the file may not work
properly.
Sampling frequency
Sampling involves taking a reading of a sound wave (analog signal) at
regular intervals and expressing the height of the wave at each reading in
digitized format (producing a digital signal).
The number of readings taken in one second is called the “sampling
frequency”. The larger the value, the closer the reproduced sound is to the
original.
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