kvantittumisvirhe

Kvantittumisvirhe, also known as quantization error, is a phenomenon that occurs in digital signal processing and digital representation of analog data. It arises when a continuous range of values is represented by a finite set of discrete values. When an analog signal is converted to a digital one, its amplitude is measured at discrete points in time, and then these measurements are quantized. Quantization involves mapping the measured analog amplitude to the nearest available discrete level. The difference between the actual analog value and its quantized digital representation is the quantization error.

This error is an inherent part of the analog-to-digital conversion process and cannot be completely eliminated, although it can be reduced. The magnitude of the quantization error is typically bounded by half of the least significant bit's value. Factors influencing the size of the quantization error include the number of bits used in the digital representation. A higher number of bits allows for more discrete levels, resulting in finer quantization and a smaller quantization error. Conversely, using fewer bits leads to coarser quantization and a larger error.

Quantization error can manifest as noise in the reconstructed analog signal. In audio processing, it can be perceived as a hiss or other unwanted artifacts. In image processing, it can lead to banding or loss of detail. Techniques like dithering are sometimes employed to mitigate the perceived effects of quantization error by adding carefully chosen random noise, which can distribute the error more evenly and make it less noticeable.