Hand-drawn animation

Traditional animation (or classical animation, cel animation or hand-drawn animation) is an animation technique where each frame is drawn by hand. The technique was the dominant form of animation in cinema until the advent of computer animation.

Animation productions begin by deciding on a story. The oral or literary source material must then be converted into an animation film script, from which the storyboard is derived. The storyboard has an appearance somewhat similar to a comic book, and it shows the sequence of shots as consecutive sketches that also indicate transitions, camera angles, and framing. The images allow the animation team to plan the flow of the plot and the composition of the imagery. The storyboard artists will have regular meetings with the director and may have to redraw or "re-board" a sequence many times before it meets final approval.

Before true animation begins, a preliminary soundtrack or "scratch track" is recorded, so that the animation may be more precisely synchronized to the soundtrack. Given the slow, methodical manner in which traditional animation is produced, it is almost always easier to synchronize animation to a pre-existing soundtrack than it is to synchronize a soundtrack to pre-existing animation. A completed cartoon soundtrack will feature music, sound effects, and dialogue performed by voice actors. However, the scratch track used during animation typically contains only the voices, any vocal songs to which characters must sing along, and temporary musical score tracks; the final score and sound effects are added during post-production.

In the case of Japanese anime, as well as most pre-1930 sound animated cartoons, the sound was post-synched; that is, the soundtrack was recorded after the film elements were finished by watching the film and performing the dialogue, music, and sound effects required. Some studios, most notably Fleischer Studios, continued to post-synch their cartoons through most of the 1930s, which allowed for the presence of the "muttered ad-libs" present in many Popeye the Sailor and Betty Boop cartoons.

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