Gammakõverit

Gammakõverit, often translated as gamma curves or gamma correction, are a concept used in image processing and video systems to describe the relationship between the pixel values and the luminance of a display. In essence, it's a way to encode and decode brightness information. A display device's response to an electrical signal is not linear; the relationship between the input signal (voltage) and the actual light output (luminance) is typically non-linear, often following a power-law function. This non-linear behavior is what gamma correction aims to address.

When images are captured or created, they are often done so with a specific gamma value in mind, usually around 2.2. This value is chosen because it's a good approximation of how the human eye perceives brightness. However, if this image is displayed on a system with a different gamma characteristic, the image's perceived brightness and contrast will be altered. Gamma correction involves applying a non-linear transformation to the image data. If the display has a gamma greater than 1, the image data is "gamma-corrected" by raising it to the power of the display's gamma. Conversely, if the display's gamma is less than 1, the image is raised to the power of 1/gamma. This process ensures that the image appears as intended across different devices and viewing conditions, maintaining visual fidelity and preventing washed-out or overly dark appearances.