Discretiseringsartefakter

Discretiseringsartefakter, also known as discretization artifacts, are a type of distortion that can occur in digital signal processing and image processing when a continuous signal or image is converted into a discrete form. This process, known as discretization, involves sampling the signal or image at regular intervals and quantizing the sampled values to a finite set of levels. The artifacts that result from this process can be categorized into two main types: aliasing and quantization noise.

Aliasing is a type of distortion that occurs when the sampling rate is too low to accurately represent the original signal or image. This can result in the introduction of high-frequency components that were not present in the original signal or image, leading to a distorted or inaccurate representation. To minimize aliasing, the sampling rate must be at least twice the highest frequency present in the original signal or image, according to the Nyquist-Shannon sampling theorem.

Quantization noise is a type of distortion that occurs when the sampled values are quantized to a finite set of levels. This can result in the introduction of noise that is not present in the original signal or image, leading to a distorted or inaccurate representation. The amount of quantization noise depends on the number of quantization levels and the statistical properties of the original signal or image. To minimize quantization noise, the number of quantization levels should be as large as possible, and the quantization levels should be chosen to minimize the distortion between the original and quantized signals or images.

Discretiseringsartefakter can have significant impacts on the quality of digital signals and images, and can limit the performance of digital signal processing and image processing systems. To minimize the impact of discretiseringsartefakter, it is important to carefully choose the sampling rate and quantization levels, and to use techniques such as anti-aliasing filters and dithering to reduce the distortion.