Kontrastitrimitys

Kontrastitrimitys, also known as contrast stretching, is a digital image processing technique used to enhance the contrast of an image. This process involves adjusting the intensity values of the pixels in an image to span the full range of possible values, thereby increasing the visibility of details in both the bright and dark areas of the image.

The technique works by identifying the minimum and maximum intensity values in the original image. These values are then mapped to the minimum and maximum values of the output image, respectively. This mapping ensures that the darkest pixel in the original image becomes the darkest pixel in the output image, and the brightest pixel in the original image becomes the brightest pixel in the output image. Intermediate pixel values are adjusted proportionally.

Kontrastitrimitys is particularly useful in images where the dynamic range of the scene is greater than the dynamic range of the imaging device. For example, in a photograph of a bright landscape with a dark foreground, the details in both the bright and dark areas may be lost. By applying contrast stretching, the details in both areas can be made more visible, resulting in a more balanced and informative image.

However, it is important to note that while contrast stretching can enhance the visibility of details, it may also amplify noise in the image. Therefore, this technique is often used in conjunction with other image processing techniques to achieve the best results. Additionally, the effectiveness of contrast stretching can be limited in images where the dynamic range of the scene is already well-utilized by the imaging device.