Kontrasztnövel

Kontrasztnövel is a term used in Hungarian to describe techniques that increase the perceived contrast of an image, scene, or display to improve the visibility of features. The goal is to make differences in luminance or color more pronounced so objects can be distinguished more easily under various viewing conditions.

In digital imaging, kontrasztnövel can be achieved through several methods, including histogram-based approaches (histogram equalization, adaptive histogram equalization such as CLAHE), contrast stretching (linear or piecewise), gamma correction, and unsharp masking which enhances local contrast by emphasizing high-frequency components. Color adjustments may involve changes in color channels or conversion to perceptually uniform color spaces.

Global methods apply the same adjustment across the image, while local or adaptive methods modify the adjustment based on neighboring pixels. Local methods, such as CLAHE or unsharp masking, can reveal fine details and textures but may introduce artifacts or amplify noise.

Applications include photography, video processing, medical imaging, astronomy, and remote sensing, where improving contrast helps analysts detect features that are otherwise hard to see. In displays and user interfaces, kontrasztnövel can improve readability under challenging lighting.

Trade-offs must be considered. Excessive kontrasztnövel can create unnatural images, edges halos, or color shifts, and can amplify noise. The choice of color space, target viewing conditions, and the degree of enhancement should be balanced with fidelity to the original scene.