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En
Glossary
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Sampling frequency and number of
quantized bits
When digitizing an analog audio signal, the number of times the
signal is sampled per second is called the sampling frequency, while
the degree of fineness when converting the sound level into a numeric
value is called the number of quantized bits. The range of rates that
can be played back is determined based on the sampling rate, while
the dynamic range representing the sound level difference is
determined by the number of quantized bits. In principle, the higher
the sampling frequency, the wider the range of frequencies that can be
played back, and the higher the number of quantized bits, the more
finely the sound level can be reproduced.
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WAV
Windows standard audio file format, which defines the method of
recording the digital data obtained by converting audio signals. It does
not specify the compression (coding) method so a desired
compression method can be used with it. By default, it is compatible
with the PCM method (no compression) and some compression
methods including the ADPCM method.
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WMA
An audio compression method developed by Microsoft Corporation. It
employs the irreversible compression method, which achieves a high
compression rate by thinning out the data of hardly audible part to the
human ears. It is said to be capable of compressing the data quantity
by about 1/22 (64 kbps) while maintaining a similar audio quality to
music CD.
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“x.v.Color”
A color space standard supported by HDMI version 1.3. It is a more
extensive color space than sRGB, and allows the expression of colors
that could not be expressed before. While remaining compatible with
the color gamut of sRGB standards, “x.v.Color” expands the color
space and can thus produce more vivid, natural images. It is
particularly effective for still pictures and computer graphics.