Rotoscope2

Rotoscoping is an animation technique in which animators trace over footage, frame by frame, for use in live-action and animated films. Originally, recorded live-action film images were projected onto a frosted glass panel and re-drawn by an animator.

The technique was invented by Max Fleischer, who used it in his series 'Out of the Inkwell' starting around 1915, with his brother Dave Fleischer dressed in a clown outfit as the live-film reference for the character 'Koko the Clown'. Max patented the method in 1917.