colorize vs colour in

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). 

colour in

verb
  • To colourise; to add colours to a black-and-white drawing, using coloured drawing equipment. 

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