In video production, inserting B-roll is a widely used technique to enrich the story and make a video more engaging. However, determining the right content and positions of B-roll and actually inserting it within the main footage can be challenging, and novice producers often struggle to get both timing and content right. We present B-Script, a system that supports B-roll video editing via interactive transcripts. B-Script has a built-in recommendation system trained on expert-annotated data, recommending users B-roll position and content. To evaluate the system, we conducted a within-subject user study with 110 participants, and compared three interface variations: a timeline-based editor, a transcript-based editor, and a transcript-based editor with recommendations. Users found it easier and were faster to insert B-roll using the transcript-based interface, and they created more engaging videos when recommendations were provided.
Integrating B-roll is a widely used technique in film editing for documentaries, reality shows or news coverage. Conventions of cinematography suggest several guidelines about B-roll editing or making cuts between shots in general. For example, it is recommended to avoid cuts when the speaker is in the middle of talking or gesturing actively because such cuts disrupt the audio-visual flow @cite_5 . Instead, a good practice is to place the cuts where there are natural pauses in the flow. Sentence endings or eye blinks can be important cues for indicating these pauses @cite_22 . On the other hand, in practice, vlogs are usually created with low production value (often with a single smartphone) and do not necessarily follow the traditional principles of professional cinematography @cite_0 . For instance, in vlogs, it is common to have frequent jump cuts or rapid shot changes to make the footage faster pace. Instead of relying on a set of rules to determine the content and positions of B-Roll, we model our recommendation algorithm based on analysis of popular vlogs from YouTube () and a database of expert annotated video edits that we collect for this purpose ().
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We present a set of tools designed to help editors place cuts and create transitions in interview video. To help place cuts, our interface links a text transcript of the video to the corresponding locations in the raw footage. It also visualizes the suitability of cut locations by analyzing the audio visual features of the raw footage to find frames where the speaker is relatively quiet and still. With these tools editors can directly highlight segments of text, check if the endpoints are suitable cut locations and if so, simply delete the text to make the edit. For each cut our system generates visible (e.g. jump-cut, fade, etc.) and seamless, hidden transitions. We present a hierarchical, graph-based algorithm for efficiently generating hidden transitions that considers visual features specific to interview footage. We also describe a new data-driven technique for setting the timing of the hidden transition. Finally, our tools offer a one click method for seamlessly removing 'ums' and repeated words as well as inserting natural-looking pauses to emphasize semantic content. We apply our tools to edit a variety of interviews and also show how they can be used to quickly compose multiple takes of an actor narrating a story. This paper introduces a bundle adjustment (BA) method that obtains accurate structure and motion from rolling shutter (RS) video sequences: RSBA. When a classical BA algorithm processes a rolling shutter video, the resultant camera trajectory is brittle, and complete failures are not uncommon. We exploit the temporal continuity of the camera motion to define residuals of image point trajectories with respect to the camera trajectory. We compare the camera trajectories from RSBA to those from classical BA, and from classical BA on rectified videos. The comparisons are done on real video sequences from an iPhone 4, with ground truth obtained from a global shutter camera, rigidly mounted to the iPhone 4. Compared to classical BA, the rolling shutter model requires just six extra parameters. It also degrades the sparsity of the system Jacobian slightly, but as we demonstrate, the increase in computation time is moderate. Decisive advantages are that RSBA succeeds in cases where competing methods diverge, and consistently produces more accurate results. Rushes footages are considered as cheap gold mine with the potential for reuse in broadcasting and filmmaking industries. However, mining “gold” from unedited videos such as rushes is challenging as the reusable segments are buried in a large set of redundant information. In this paper, we propose a unified framework for stock footage classification and summarization to support video editors in navigating and organizing rushes videos. Our approach is composed of two steps. First, we employ motion features to filter the undesired camera motion and locate the stock footage. A hierarchical hidden Markov model (HHMM) is proposed to model the motion feature distribution and classify video segments into different categories to decide their potential for reuse. Second, we generate a short video summary to facilitate quick browsing of the stock footages by including the objects and events that are important for storytelling. For objects, we detect the presence of persons and moving objects. For events, we extract a set of features to detect and describe visual (motion activities and scene changes) and audio events (speech clips). A representability measure is then proposed to select the most representative video clips for video summarization. Our experiments show that the proposed HHMM significantly outperforms other methods based on SVM, FSM, and HMM. The automatically generated rushes summaries are also demonstrated to be easy-to-understand, containing little redundancy, and capable of including ground-truth objects and events with shorter durations and relatively pleasant rhythm based on the TRECVID 2007, 2008, and our subjective evaluations. This paper presents a technique to automatically stitch multiple images at varying orientations and exposures to create a composite panorama that preserves the angular extent and dynamic range of the inputs. The main contribution of our method is that it allows for large exposure differences, large scene motion or other misregistrations between frames and requires no extra camera hardware. To do this, we introduce a two-step graph cut approach. The purpose of the first step is to fix the positions of moving objects in the scene. In the second step, we fill in the entire available dynamic range. We introduce data costs that encourage consistency and higher signal-to-noise ratios, and seam costs that encourage smooth transitions. Our method is simple to implement and effective. We demonstrate the effectiveness of our approach on several input sets with varying exposures and camera orientations.