Quantization Noise
Quantization noise is inherent in the amplitude quantization process and occurs
in the analog-to-digital converter, ADC. The noise is additive and independent
of the signal when the number of levels L >= 16. This is equivalent to
B >= 4 bits. (See Section 2.1.) For a signal that has been converted
to electrical form and thus has a minimum and maximum electrical value, eq. is
the appropriate formula for determining the SNR. If the ADC is adjusted
so that 0 corresponds to the minimum electrical value and
2B-1 corresponds to the maximum electrical value then:
Quantization noise -
For B >= 8 bits, this means a SNR >= 59 dB. Quantization
noise can usually be ignored as the total SNR of a complete system is
typically dominated by the smallest SNR. In CCD cameras this is photon
noise.