Quantization is the second half of digitizing audio, after sampling: each measured sample, a continuous voltage, is rounded to the nearest value the bit depth can represent. With 16 bits there are 65,536 possible levels; with 24 bits, over 16 million. The rounding error is quantization noise, and at low bit depths it correlates with the signal, producing audible distortion on quiet passages rather than benign hiss. Dithering — adding a tiny controlled noise before rounding — decorrelates that error and trades the distortion for a constant, unobtrusive noise floor. Quantization is why bit depth sets dynamic range, and why you dither whenever you reduce it.
The book · Volume 4 of 7
Audio for Video: A Complete Guide to Sound in Video Products: From PCM and Codecs to Loudness, Accessibility, and Real-Time Voice Processing
Quantization is where a continuous signal becomes numbers, and the rounding error it leaves sets the noise floor of everything downstream. This volume explains quantization in depth with bit depth, dynamic range, dither and noise shaping, so you can choose word lengths for capture, processing and delivery without hidden quality loss. Written by Nikolay Sapunov, CEO at Fora Soft.
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