What does brightness and contrast mean

Increasing brightness of an image will light out all colors so the original light ones will become up to white. Reversely, decreasing brightness will darken all colors so the original shaded ones will become up to black.

Increasing contrast on an image will increase the difference between light and dark areas so light areas will become lighter and dark areas will become darker. The three square boxes have pixel values of 75, and , from left-to-right. Each square contains two triangles with pixel values only slightly different from their surroundings.

In other. Figure shows how adjustment of the contrast and brightness allows different features in the image to be visualized. In a , the brightness and contrast are set at the normal level, as indicated by the B and C slide bars at the left side of the image.

Now turn your attention to the graph shown with each image, called an output transform , an output look-up table , or a gamma curve. This controls the hardware that displays the image. The value of each pixel in the stored image, a number between 0 and , is passed through this look-up table to produces another number between 0 and This new digital number drives the video intensity circuit, with 0 through being transformed into black through white, respectively.

That is, the look-up table maps the stored numbers into the displayed brightness. Figure a shows how the image appears when the output transform is set to do nothing , i. Each pixel in the noisy background is a random shade of gray, equally distributed between black and white. The three boxes are displayed as dark, medium and light, clearly distinct from each other.

The problem is, the triangles inside each square cannot be easily seen; the contrast is too low for the eye to distinguished these regions from their surroundings. Increasing the brightness shifts the output transform to the left , while decreasing the brightness shifts it to the right. Artificial Intelligence. Cloud Computing. Data Science. Angular 7. Machine Learning. Data Structures. Operating System. Computer Network.

Compiler Design. Computer Organization. Discrete Mathematics. Still both the images are same, now we will perform some operations on image1 , due to which it becomes brighter then the second one. What we will do is, that we will simply add a value of 1 to each of the matrix value of image 1. After adding the image 1 would something like this.

Now what we will do, is that we will add 50 to each of the matrix value of the image 1 and see what the image has become. Now you can see that the image 1 is slightly brighter then the image 2. We go on, and add another 45 value to its matrix of image 1, and this time we compare again both images.