The kudus are two species of antelope of the genus Tragelaphus: Lesser kudu, Tragelaphus imberbis, of eastern Africa Greater kudu, Tragelaphus strepsiceros, of eastern and southern Africa Like many other antelope, male kudus can be found in bachelor groups, but they are more likely to be solitary. Their dominance displays tend not to last long and are generally fairly peaceful, consisting of one male making himself look big by making his hair stand on end. When males do have a face-off, they will lock their horns in a competition to determine the stronger puller; kudus' necks enlarge during the mating season for this reason.
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.