Additional Excercises for Chapter 5

1. Rescaling
   Use Pixel Jelly to open each of the image files below. For each image you should rescale the image such that 1) the green channel is deleted 2) the green channel is scaled upward by 20% and brightened by 20 levels 3) the green channel is inverted and 4) the red and blue channels are deleted but the green channel is left intact.
   • Renoir
   • Van Gogh Sunflowers
   • Turtle


2. Histogram equalization
   Use Pixel Jelly to equalize each of the images below. Perform equalization two ways: on the brightness band and on each band independently. Make sure to examine the histograms of each image before equalization and after. Include the resulting images in your report and comment on the results.
   • Balloons in the morning (courtesy of user 'wools' on flickr) : what is written on the right-most ballon?
   • Imperial College Queen (courtesy of user 'dumbledad' on flickr) : what is written at the base of the statue?
   • Dark monkey (courtesy of Kenny Hunt. This underexposed photo is one of my own unfortunate shapshots).
   • Bright bear (courtesy of Kenny Hunt. Again ... another unfortunate photo).


3. Image blending
   Use Pixel Jelly to open the image below. Create an image depicting a white ellipse on a black backround having the same resolution as the source image below (select 'Edit-Create'). Invert the white elliplse. Denote the source image below as S1, the white ellipse image as S2 and S3 as the inverse of S2. Use Pixel Jelly to combine S1 with both S2 and S3 using each of the supported blending modes (add, subtract, XOR, OR, etc...). For each blending operation, here denoted as •, you should generate the output of S1•S2, S2•S1, S1•S3, S3•S1 and S1•S1.
   • Stained Glass Window