Onion skinning is a 2D computer graphics

2D computer graphics

2D computer graphics is the computer-based generation of digital images—mostly from two-dimensional models and by techniques specific to them...

 term for a technique used in creating animated cartoons

Animation

Animation is the rapid display of a sequence of images of 2-D or 3-D artwork or model positions in order to create an illusion of movement. The effect is an optical illusion of motion due to the phenomenon of persistence of vision, and can be created and demonstrated in several ways...

 and editing movies to see several frames at once. This way, the animator or editor can make decisions on how to create or change an image based on the previous image in the sequence.

In traditional cartoon animation, the individual frames of a movie were initially drawn on thin onionskin

Onionskin

Onionskin or onion skin is a thin, light-weight, strong, often translucent paper. It was usually used with carbon paper for typing duplicates in a typewriter, for permanent records where low bulk was important, or for airmail correspondence...

 paper over a light source. The animators (mostly inbetweeners) would put the previous and next drawings exactly beneath the working drawing, so that they could draw the 'in between' to give a smooth motion.

In computer software, this effect is achieved by making frames translucent and projecting them on top of each other.

This effect can also be used to create motion blur

Motion blur

Motion blur is the apparent streaking of rapidly moving objects in a still image or a sequence of images such as a movie or animation. It results when the image being recorded changes during the recording of a single frame, either due to rapid movement or long exposure.- Photography :When a camera...

s, as seen in The Matrix

The Matrix (franchise)

The Matrix is a science fiction action franchise created by Andy and Larry Wachowski and distributed by Warner Bros. Pictures. The series began with the 1999 film The Matrix and later spawned two sequels; The Matrix Reloaded and The Matrix Revolutions, both released in 2003, thus forming a trilogy...

when characters dodge bullets.

External links

• Onion Skinning in I Can Animate
• Onion skinning in SAM Animation
• Shape Shifter at Aniboom. To see onion skinning, press 'o' then create a shape, add a frame, move your shape, and repeat.