morphing

Morphing, in digital media, refers to the process of transforming one image or shape into another through a sequence of intermediate frames. The goal is a smooth, illusionary transition by altering geometry, color, and texture in a controlled manner.

Techniques combine two main ideas: establishing correspondences between the source and target, and applying warping and blending to produce in-between frames. Common approaches include feature-based methods, which map corresponding points or landmarks, and mesh- or grid-based methods, which deform an underlying mesh to interpolate shapes.

A typical workflow includes aligning inputs, computing a per-pixel or per-vertex correspondence, warping the geometry of each frame, and blending image data across frames. Interpolation can be linear or non-linear, and artists often employ easing functions to control the pace of the transition. Modern systems may also incorporate texture synthesis or color correction to maintain realism.

Types and domains: Image morphing transforms one 2D image into another; 3D morphing (or morph target animation) blends different shapes or meshes to produce new forms; audio morphing applies similar ideas to sound signals using spectral or time-domain methods.

History and usage: The technique emerged in the 1980s as computer graphics matured and became widely used in film and television during the 1990s. It is used for visual effects, character transformations, logo animation, and data visualization, among others. Limitations include artifacts such as ghosting or unnatural warping when correspondences are imperfect, as well as computational cost.

In biology, metamorphosis refers to real-world transformations of organisms and is distinct from digital morphing.