CS 106A Lecture Notes - Lecture 18: Executable
Document Summary
2-d arrays (cont. : shrinking an image to half its original dimensions. When we brighten an image, we create a new array based on the original one, change the colors, and then set that array as the one to use. For this array, however, we need half as many pixels in order to shrink the image. We can loop over the result array (which is half the size of the original array) for convenience. We should shrink every 2px x 2px block to a 1x1 block. In order to do that, for every 4 pixels in the original picture, replace it with 1 pixel result[r][c] = pixels[r * 2][c * 2]; (shrink by half: enlarging an image to twice its original dimensions. Set the result array to be twice as many pixels as the original array result[r][c] = pixels[r / 2][c / 2]; (shrink by half) Classes and objects (difficult conceptual topic: class examples.