“In digital signal processing, sampling is the process of breaking up a continuous signal to a discrete signal”. This method is commonly used in the conversion of a sound signal from analog to digital. The process breaks up the analog sound waves, with continuous values of amplitude, into intervals along the time axis to produce a sequence of signals. As a result, the values on x-axis (time intervals) are converted from continuous, to discrete values, with each Time interval corresponding to a specific value of amplitude.
So, instead of having a continuous analog signal, a new digitalized signal is produced with single maximum amplitude, representing the whole time interval. The resulting signal is called the Pulse Amplitude Modulated Signal, which is half continuous and cannot be represented digitally. So, a second step of discretization, called quantization, is carried out.
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“In digital signal processing, quantization is the process of mapping a larger set of values to a smaller set”. This process is usually carried out to digitally represent a partially discretized signal with a single continuous value of amplitude representing each interval of time.
In this process, the continuous amplitude values are either rounded up or down to the nearest predetermined values, to get a finite set of values rather than an infinite number of values. This type of signal is called the Pulse Code Modulated Signal.
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