Wendigo is a mythological creature or evil spirit which originates from the folklore of First Nations based in and around the East Coast forests of Canada, the Great Plains region of the United States, and the Great Lakes region of the United States and Canada, grouped in modern ethnology as speakers of Algonquian-family languages. The wendigo is often said to be a malevolent spirit, sometimes depicted as a creature with human-like characteristics, which possesses human beings. The wendigo is known to invoke feelings of insatiable greed/hunger, the desire to cannibalize other humans, as well as the propensity to commit murder in those that fall under its influence. At odds with its portrayals in twentieth-century and twenty-first-century settler culture, in indigenous representations the wendigo is described as a giant humanoid with a heart of ice; a foul stench or sudden, unseasonable chill might precede its approach. Possibly due to longtime identification by Europeans with their own superstitions about werewolves, for example as mentioned in The Jesuit Relations below, Hollywood film representations often label human/beast hybrids featuring antlers or horns with the "wendigo" name, but such animal features do not appear in the original indigenous stories.
Chroma key compositing, or chroma keying, is a special effects / post-production technique for compositing (layering) two images or video streams together based on color hues (chroma range). The technique has been used heavily in many fields to remove a background from the subject of a photo or video – particularly the newscasting, motion picture and videogame industries. A color range in the foreground footage is made transparent, allowing separately filmed background footage or a static image to be inserted into the scene. The chroma keying technique is commonly used in video production and post-production. This technique is also referred to as color keying, colour-separation overlay (CSO; primarily by the BBC), or by various terms for specific color-related variants such as green screen, and blue screen – chroma keying can be done with backgrounds of any color that are uniform and distinct, but green and blue backgrounds are more commonly used because they differ most distinctly in hue from most human skin colors. No part of the subject being filmed or photographed may duplicate the color used as the backing.