Colorize

Film colorization (American English; or colourisation/colorisation [both British English], or colourization [Canadian English and Oxford English]) is any process that adds color to black-and-white, sepia, or other monochrome moving-picture images. It may be done as a special effect, to "modernize" black-and-white films, or to restore color segregation. The first examples date from the early 20th century, but colorization has become common with the advent of digital image processing.