kvantiseringsfejl

Kvantiseringsfejl, also known as quantization error, is a phenomenon that occurs in digital signal processing when a continuous analog signal is converted into a discrete digital signal. This process, called analog-to-digital conversion (ADC), involves sampling the analog signal at regular intervals and then assigning each sample a numerical value from a finite set of possible values. The quantization error arises because the discrete values cannot perfectly represent the continuous range of the original analog signal.

The magnitude of the quantization error for any given sample is the difference between the true analog value and the quantized digital value. This error is typically a random noise that is introduced into the signal. The size of the error is directly related to the number of bits used in the quantization process. A higher number of bits allows for a larger number of discrete levels, thus reducing the difference between the analog and digital representations and consequently minimizing the quantization error. Conversely, using fewer bits leads to coarser quantization and a larger, more noticeable error.

Quantization error can manifest as distortion, noise, or loss of detail in the digitized signal. In applications like audio and image processing, it can be perceived as a loss of fidelity or the introduction of unwanted artifacts. Techniques such as dithering, which involves adding a small amount of random noise before quantization, can be employed to spread the quantization error across a wider frequency range, making it less perceptible to human senses. Understanding and managing quantization error is crucial for achieving high-quality digital representations of analog signals.