Video retrieval based on user-specified appearance and application to animation synthesis

In our research group, we investigate techniques for retrieving videos based on user-specified appearances. In this paper, we introduce two of our research activities. First, we present a user interface for quickly and easily retrieving scenes of a desired appearance from videos. Given an input image, our system allows the user to sketch a transformation of an object inside the image, and then retrieves scenes showing this object in the userspecified transformed pose. Our method employs two steps to retrieve the target scenes. We first apply a standard image-retrieval technique based on feature matching, and find scenes in which the same object appears in a similar pose. Then we find the target scene by automatically forwarding or rewinding the video, starting from the frame selected in the previous step. When the user-specified transformation is matched, we stop forwarding or rewinding, and thus the target scene is retrieved. We demonstrate that our method successfully retrieves scenes of a racing car, a running horse, and a flying airplane with user-specified poses and motions. Secondly, we present a method for synthesizing fluid animation from a single image, using a fluid video database. The user inputs a target painting or photograph of a fluid scene. Employing the database of fluid video examples, the core algorithm of our technique then automatically retrieves and assigns appropriate fluid videos for each part of the target image. The procedure can thus be used to handle various paintings and photographs of rivers, waterfalls, fire, and smoke, and the resulting animations demonstrate that it is more powerful and efficient than our prior work.