An animation distributing server receives a request from a user to distribute animation. The server selects key frames to be transmitted and transmits the selected key frames to the user. Thereafter, compact interpolation data, for interpolating between the key frames, are generated, a digital watermarking processing is performed thereon, and the interpolation data are transmitted to the user. A viewer, for composing an animation from the key frames and interpolation data, may be sent to the user. The key frames and the interpolation data are transmitted separately in a manner such that they can be integrated at the user side.