tussenraming

Tussenraming is a term used in animation and film production to describe the creation of in-between frames between keyframes in order to produce smooth motion. The word is a compound of tussen (between) and raming (framing), and in Dutch usage it is equivalent to the English term in-betweening or tweening. In traditional cel animation the process involved drawing a sequence of frames by an animator to bridge key poses drawn by different artists. In modern computer animation, tussenraming is often performed automatically by software, generating intermediate positions, rotations, scales, or morphs between keyframes, sometimes guided by easing curves or user-set parameters. The number of tussenramingen between two keyframes depends on the frame rate and the desired motion speed; common practice ranges from a handful of frames to dozens per pose, especially at lower frame rates. Artists may also adjust individual in-betweens to preserve timing, weight, and style, a practice known as "pose-to-pose" with careful follow-through.

The technique is closely related to onion-skinning, which lets animators see several adjacent frames simultaneously to plan the transitions. While automation has reduced manual workload, skilled animators still shape in-between frames to maintain exaggeration and appeal. In 3D animation and motion graphics, the term is often replaced by "tweening" or "interpolation" within the animation engine.