Introduction - Java Software Solutions: Foundations of Program Design - page 6

Sound wave Analog signal of the sound wave

FIGURE 1.3 A sound wave and an electronic analog signal
that represents the wave

can be used to generate a continuous analog signal that is “close enough” to the
original. In most cases, the goal is to create a reproduction of the original signal
that is good enough to satisfy the human senses.
Figure 1.4 shows the sampling of an analog signal. When analog information
is converted to a digital format by breaking it into pieces, we say it has been
digitized. Because the changes that occur in a signal between samples are lost, the
sampling rate must be sufficiently fast.

Information can be lost
between samples

Analog signal

Sampling process

Sampled values 12 11 39 40 7 14 47

FIGURE 1.4 Digitizing an analog signal by sampling