Image Processing

Question 1

What a color histogram is and what we can derive from it

Answer 1

A color histogram is a graphical representation of the distribution of colors in an image, it shows the distribution of the different color channels and can be used to evaluate the overall exposure and color balance of an image.

Question 2

What effects occurred in over- or underexposed images and how we can change the color values

Answer 2

Over- or underexposed images can have a loss of detail and color, to change the color values we can use tools such as Levels or Curves

Question 3

What happens to the color values when adjusting brightness / contrast of an image

Answer 3

Adjusting the brightness/contrast of an image changes the overall tonal distribution of the image and may cause loss of details in highlights and shadows

Question 4

What gamma correction is and why we need it

Answer 4

Gamma correction is a technique used to adjust the overall brightness of an image and make sure that the image appears correctly on different displays, by adjusting the non-linear relationship between the signal level and the light emitted