Suppose image file values are in 0..255 in each color channel. If we define R =...

 

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Suppose image file values are in 0..255 in each color channel. If we define R = R/255 for the red channel, we wish to carry out gamma correction by passing a new value R' to the display device, with R' ~ R/2.0 It is common to carry out this operation using integer math. Suppose we approximate the calculation as creating new integer values in 0..255 via (int) (255 (R1/2.0)) (a) Comment (very roughly) on the effect of this operation on the number of actually available levels for display. Hint: Coding this up in any language will help you understand the mechanism at work better and will allow you to simply count the output levels. (b) Which end of the levels 0..255 is affected most by gamma correction the high end (near 255)? Why? How much at each end? the low end (near (0) or Suppose image file values are in 0..255 in each color channel. If we define R = R/255 for the red channel, we wish to carry out gamma correction by passing a new value R' to the display device, with R' ~ R/2.0 It is common to carry out this operation using integer math. Suppose we approximate the calculation as creating new integer values in 0..255 via (int) (255 (R1/2.0)) (a) Comment (very roughly) on the effect of this operation on the number of actually available levels for display. Hint: Coding this up in any language will help you understand the mechanism at work better and will allow you to simply count the output levels. (b) Which end of the levels 0..255 is affected most by gamma correction the high end (near 255)? Why? How much at each end? the low end (near (0) or