colorize vs variegate

colorize

verb
  • To add color to. 

  • (Canadian spelling, acceptable) To convert black and white media to color by digital post production (as is often done in digital photography and in video special effects). 

variegate

verb
  • To change the appearance of something, especially by covering with patches or streaks of different colour. 

  • To add variety to something. 

  • To dapple. 

adj
  • variegated 

How often have the words colorize and variegate occurred in a corpus of books? (source: Google Ngram Viewer )