Abstract We propose an automatic method for generating flight summaries of prescribed duration, given any planed 3D trajectory of a flying object. The challenge is to select relevant time‐ellipses, while keeping and adequately framing the most interesting parts of the trajectory, and enforcing cinematographic rules between the selected shots. Our solution optimizes the visual quality of the output video both in terms of camera view and film editing choices, thanks to a new optimization technique, designed to jointly optimize the selection of the interesting parts of a flight, and the camera animation parameters over time. To our best knowledge, this solution is the first one to address camera control, film editing, and trajectory summarizing at once. Ablation studies demonstrate the visual quality of the flights summaries we generate compared to alternative methods.

Tracking in a cinematic way a moving target inside a 3D dynamic environment remains a challenging problem. This requires to simultaneously ensure a low computational cost, a good degree of reactivity and a high cinematic quality despite sudden changes. In this paper, we draw on the idea of Motion-Predictive Control to propose an efficient real-time camera tracking technique which ensures these properties. Our approach relies on the predicted motion of a target to create and evaluate a very large number of camera motions using hardware ray casting. Our evaluation of camera motions includes a range of cinematic properties such as distance to target, visibility, collision, smoothness and jitter. Experiments are conducted to display the benefits of the approach with relation to prior work.

Abstract Efficient visibility computation is a prominent requirement when designing automated camera control techniques for dynamic 3D environments; computer games, interactive storytelling or 3D media applications all need to track 3D entities while ensuring their visibility and delivering a smooth cinematic experience. Addressing this problem requires to sample a large set of potential camera positions and estimate visibility for each of them, which in practice is intractable despite the efficiency of ray‐casting techniques on recent platforms. In this work, we introduce a novel GPU‐rendering technique to efficiently compute occlusions of tracked targets in Toric Space coordinates – a parametric space designed for cinematic camera control. We then rely on this occlusion evaluation to derive an anticipation map predicting occlusions for a continuous set of cameras over a user‐defined time window. We finally design a camera motion strategy exploiting this anticipation map to minimize the occlusions of tracked entities over time. The key features of our approach are demonstrated through comparison with traditionally used ray‐casting on benchmark scenes, and through an integration in multiple game‐like 3D scenes with heavy, sparse and dense occluders.

Abstract The placement of lights in a 3D scene is a technical and artistic task that requires time and trained skills. Most 3D modelling tools only provide a direct control of light sources, through the manipulation of parameters such as size, location, flux (the perceived power of light) or opening angle (the light frustum). Approaches have been relying on automated or semi‐automated techniques to relieve users from such low‐level manipulations at the expense of an important computational cost. In this paper, guided by discussions with experts in scene and object lighting, we propose an indirect control of area light sources. We first formalize the classical 3‐point lighting design principle (key‐light, fill‐lights and back/rim‐lights) in a parametric model. Given a key‐light placed in the scene, we then provide a computational approach to (i) automatically compute the position and size of fill‐lights and back/rim‐lights by analyzing the geometry of 3D character, and (ii) automatically compute the flux and size of key, fill and back/rim lights, given a sample reference image in a computationally efficient way. Results demonstrate the benefits of the approach on the quick lighting of 3D characters, and further demonstrate the feasibility of interactive control of multiple lights through image features.

Quadrotor drones equipped with high-quality cameras have rapidly raised as novel, cheap, and stable devices for filmmakers. While professional drone pilots can create aesthetically pleasing videos in short time, the smooth—and cinematographic—control of a camera drone remains challenging for most users, despite recent tools that either automate part of the process or enable the manual design of waypoints to create drone trajectories. This article moves a step further by offering high-level control of cinematographic drones for the specific task of framing dynamic targets. We propose techniques to automatically and interactively plan quadrotor drone motions in dynamic three-dimensional (3D) environments while satisfying both cinematographic and physical quadrotor constraints. We first propose the Drone Toric Space , a dedicated camera parameter space with embedded constraints, and derive some intuitive on-screen viewpoint manipulators. Second, we propose a dedicated path planning technique that ensures both that cinematographic properties can be enforced along the path and that the path is physically feasible by a quadrotor drone. At last, we build on the Drone Toric Space and the specific path planning technique to coordinate the motion of multiple drones around dynamic targets. A number of results demonstrate the interactive and automated capacities of our approaches on different use-cases.

We describe an optimization-based approach for automatically creating well-edited movies from a 3D animation. While previous work has mostly focused on the problem of placing cameras to produce nice-looking views of the action, the problem of cutting and pasting shots from all available cameras has never been addressed extensively. In this paper, we review the main causes of editing errors in literature and propose an editing model relying on a minimization of such errors. We make a plausible semi-Markov assumption, resulting in a dynamic programming solution which is computationally efficient. We also show that our method can generate movies with different editing rhythms and validate the results through a user study. Combined with state-of-the-art cinematography, our approach therefore promises to significantly extend the expressiveness and naturalness of virtual movie-making.

When creating real or computer graphics movies, the questions of how to layout elements on the screen, together with how to move the cameras in the scene are crucial to properly conveying the events composing a narrative. Though there is a range of techniques to automatically compute camera paths in virtual environments, none have seriously considered the problem of generating realistic camera motions even for simple scenes. Among possible cinematographic devices, real cinematographers often rely on camera rails to create smooth camera motions which viewers are familiar with. Following this practice, in this paper we propose a method for generating virtual camera rails and computing smooth camera motions on these rails. Our technique analyzes characters motion and user-defined framing properties to compute rough camera motions which are further refined using constrained-optimization techniques. Comparisons with recent techniques demonstrate the benefits of our approach and opens interesting perspectives in terms of creative support tools for animators and cinematographers.

A large range of computer graphics applications such as data visualization or virtual movie production require users to position and move viewpoints in 3D scenes to effectively convey visual information or tell stories. The desired viewpoints and camera paths are required to satisfy a number of visual properties ( e.g. size, vantage angle, visibility, and on-screen position of targets). Yet, existing camera manipulation tools only provide limited interaction methods and automated techniques remain computationally expensive. In this work, we introduce the Toric space , a novel and compact representation for intuitive and efficient virtual camera control. We first show how visual properties are expressed in this Toric space and propose an efficient interval-based search technique for automated viewpoint computation. We then derive a novel screen-space manipulation technique that provides intuitive and real-time control of visual properties. Finally, we propose an effective viewpoint interpolation technique which ensures the continuity of visual properties along the generated paths. The proposed approach (i) performs better than existing automated viewpoint computation techniques in terms of speed and precision, (ii) provides a screen-space manipulation tool that is more efficient than classical manipulators and easier to use for beginners, and (iii) enables the creation of complex camera motions such as long takes in a very short time and in a controllable way. As a result, the approach should quickly find its place in a number of applications that require interactive or automated camera control such as 3D modelers, navigation tools or 3D games.

We present the Director's Lens, an intelligent interactive assistant for crafting virtual cinematography using a motion-tracked hand-held device that can be aimed like a real camera. The system employs an intelligent cinematography engine that can compute, at the request of the filmmaker, a set of suitable camera placements for starting a shot. These suggestions represent semantically and cinematically distinct choices for visualizing the current narrative. In computing suggestions, the system considers established cinema conventions of continuity and composition along with the filmmaker's previous selected suggestions, and also his or her manually crafted camera compositions, by a machine learning component that adapts shot editing preferences from user-created camera edits. The result is a novel workflow based on interactive collaboration of human creativity with automated intelligence that enables efficient exploration of a wide range of cinematographic possibilities, and rapid production of computer-generated animated movies.

This demonstration shows how an automated assistant encoded with knowledge of cinematography practice can offer suggested viewpoints to a filmmaker operating a hand-held motion-tracked virtual camera device. Our system, called Director's Lens, uses an intelligent cinematography engine to compute, at the request of the filmmaker, a set of suitable camera placements for starting a shot that represent semantically and cinematically distinct choices for visualizing the current narrative. Editing decisions and hand-held camera compositions made by the user in turn influence the system's suggestions for subsequent shots. The result is a novel virtual cinematography workflow that enhances the filmmaker's creative potential by enabling efficient exploration of a wide range of computer-suggested cinematographic possibilities.