Camera-equipped unmanned aerial vehicles (UAVs), or ``drones,'' are a recent addition to standard audiovisual shooting technologies. As drone cinematography is expected to further revolutionize media production, this paper presents an overview of the state-of-the-art in this area, along with a brief review of current commercial UAV technologies and legal restrictions on their deployment. A novel taxonomy of UAV cinematography visual building blocks, in the context of filming outdoor events where targets (e.g., athletes) must be actively followed, is additionally proposed. Such a taxonomy is necessary for progress in intelligent/autonomous UAV shooting, which has the potential of addressing current technology challenges. Subsequently, the concepts and advantages inherent in multiple-UAV cinematography are introduced. The core of multiple-UAV cinematography consists in identifying different combinations of multiple single-UAV camera motion types, assembled in meaningful sequences. Finally, based on the defined UAV/camera motion types, tools for managing a partially autonomous, multiple-UAV fleet from the director's point of view are presented. Although the overall focus is on cinematic coverage of sports events, the majority of our contributions also apply in different scenarios, such as movies/TV production, newsgathering, or advertising.
Image data augmentation constitutes a critical methodology in modern computer vision tasks, since it can facilitate towards enhancing the diversity and quality of training datasets; thereby, improving the performance and robustness of machine learning models in downstream tasks. In parallel, augmentation approaches can also be used for editing/modifying a given image in a context- and semantics-aware way. Diffusion Models (DMs), which comprise one of the most recent and highly promising classes of methods in the field of generative Artificial Intelligence (AI), have emerged as a powerful tool for image data augmentation, capable of generating realistic and diverse images by learning the underlying data distribution. The current study realizes a systematic, comprehensive and in-depth review of DM-based approaches for image augmentation, covering a wide range of strategies, tasks and applications. In particular, a comprehensive analysis of the fundamental principles, model architectures and training strategies of DMs is initially performed. Subsequently, a taxonomy of the relevant image augmentation methods is introduced, focusing on techniques regarding semantic manipulation, personalization and adaptation, and application-specific augmentation tasks. Then, performance assessment methodologies and respective evaluation metrics are analyzed. Finally, current challenges and future research directions in the field are discussed.
12 March 2024 in Engineering Applications of Artificial Intelligence
Autonomous UAV cinematography is an active research field with exciting potential for the media industry. It bears the promise of greatly facilitating UAV shooting for various applications, while significantly reducing the costs compared to manual shooting. However, the general problem has not been clearly defined and the challenges arising from current legislation and technology restrictions have not been fully charted. A complete overview of issues related to autonomous UAV cinematography is needed, pertaining to the current situation in the field, so as to guide immediate-future research. The purpose of this paper is to lay exactly this groundwork, with the expectation of providing a global perspective to multiple domain-specific research communities. The outlined issues are partitioned into challenges deriving from ethical/legal/safety considerations and from operational/production requirements. A brief survey of current technological solutions, including their limitations, is also provided for each issue.
The recent mass commercialization of affordable unmanned aerial vehicles (UAVs), known as drones, has significantly altered the media production landscape, allowing for the easy acquisition of impressive aerial footage. Relevant applications include the production of movies, TV shows, or commercials as well as the filming of outdoor events or news stories. In the near future, increased drone autonomy is expected to reduce shooting costs and shift focus to the creative process, rather than the minutiae of UAV operation. This article introduces and surveys the emerging field of autonomous UAV filming and familiarizes the reader with the inherent signal processing aspects and challenges.