43 research outputs found
TRECVID 2008 - goals, tasks, data, evaluation mechanisms and metrics
The TREC Video Retrieval Evaluation (TRECVID) 2008 is a TREC-style video analysis and retrieval evaluation, the goal of which remains to promote progress in content-based exploitation of digital video via open, metrics-based evaluation. Over the last 7 years this effort has yielded a
better understanding of how systems can effectively accomplish such processing and how one can reliably benchmark their performance. In 2008, 77 teams (see Table 1) from various research organizations --- 24 from
Asia, 39 from Europe, 13 from North America, and 1 from Australia --- participated in one or more of five tasks: high-level feature extraction, search (fully automatic, manually assisted, or interactive), pre-production video (rushes) summarization, copy detection, or surveillance event detection. The copy detection and surveillance event detection tasks are being run for the first time in TRECVID.
This paper presents an overview of TRECVid in 2008
On-line video abstraction
Tesis doctoral inédita. Universidad Autónoma de Madrid, Escuela Politécnica Superior, abril de 201
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Divide-and-conquer based summarization framework for extracting affective video content
YesRecent advances in multimedia technology have led to tremendous increases in the available volume of video data, thereby creating a major requirement for efficient systems to manage such huge data volumes. Video summarization is one of the key techniques for accessing and managing large video libraries. Video summarization can be used to extract the affective contents of a video sequence to generate a concise representation of its content. Human attention models are an efficient means of affective content extraction. Existing visual attention driven summarization frameworks have high computational cost and memory requirements, as well as a lack of efficiency in accurately perceiving human attention. To cope with these issues, we propose a divide-and-conquer based framework for an efficient summarization of big video data. We divide the original video data into shots, where an attention model is computed from each shot in parallel. Viewer's attention is based on multiple sensory perceptions, i.e., aural and visual, as well as the viewer's neuronal signals. The aural attention model is based on the Teager energy, instant amplitude, and instant frequency, whereas the visual attention model employs multi-scale contrast and motion intensity. Moreover, the neuronal attention is computed using the beta-band frequencies of neuronal signals. Next, an aggregated attention curve is generated using an intra- and inter-modality fusion mechanism. Finally, the affective content in each video shot is extracted. The fusion of multimedia and neuronal signals provides a bridge that links the digital representation of multimedia with the viewerâs perceptions. Our experimental results indicate that the proposed shot-detection based divide-and-conquer strategy mitigates the time and computational complexity. Moreover, the proposed attention model provides an accurate reflection of the user preferences and facilitates the extraction of highly affective and personalized summaries.Supported by the ICT R&D program of MSIP/IITP. [2014(R0112-14-1014), The Development of Open Platform for Service of Convergence Contents]
Automatic summarization of narrative video
The amount of digital video content available to users is rapidly increasing. Developments in computer, digital network, and storage technologies all contribute to broaden the offer of digital video. Only usersâ attention and time remain scarce resources. Users face the problem of choosing the right content to watch among hundreds of potentially interesting offers. Video and audio have a dynamic nature: they cannot be properly perceived without considering their temporal dimension. This property makes it difficult to get a good idea of what a video item is about without watching it. Video previews aim at solving this issue by providing compact representations of video items that can help users making choices in massive content collections. This thesis is concerned with solving the problem of automatic creation of video previews. To allow fast and convenient content selection, a video preview should take into consideration more than thirty requirements that we have collected by analyzing related literature on video summarization and film production. The list has been completed with additional requirements elicited by interviewing end-users, experts and practitioners in the field of video editing and multimedia. This list represents our collection of user needs with respect to video previews. The requirements, presented from the point of view of the end-users, can be divided into seven categories: duration, continuity, priority, uniqueness, exclusion, structural, and temporal order. Duration requirements deal with the durations of the preview and its subparts. Continuity requirements request video previews to be as continuous as possible. Priority requirements indicate which content should be included in the preview to convey as much information as possible in the shortest time. Uniqueness requirements aim at maximizing the efficiency of the preview by minimizing redundancy. Exclusion requirements indicate which content should not be included in the preview. Structural requirements are concerned with the structural properties of video, while temporal order requirements set the order of the sequences included in the preview. Based on these requirements, we have introduced a formal model of video summarization specialized for the generation of video previews. The basic idea is to translate the requirements into score functions. Each score function is defined to have a non-positive value if a requirement is not met, and to increase depending on the degree of fulfillment of the requirement. A global objective function is then defined that combines all the score functions and the problem of generating a preview is translated into the problem of finding the parts of the initial content that maximize the objective function. Our solution approach is based on two main steps: preparation and selection. In the preparation step, the raw audiovisual data is analyzed and segmented into basic elements that are suitable for being included in a preview. The segmentation of the raw data is based on a shot-cut detection algorithm. In the selection step various content analysis algorithms are used to perform scene segmentation, advertisements detection and to extract numerical descriptors of the content that, introduced in the objective function, allow to estimate the quality of a video preview. The core part of the selection step is the optimization step that consists in searching the set of segments that maximizes the objective function in the space of all possible previews. Instead of solving the optimization problem exactly, an approximate solution is found by means of a local search algorithm using simulated annealing. We have performed a numerical evaluation of the quality of the solutions generated by our algorithm with respect to previews generated randomly or by selecting segments uniformly in time. The results on thirty content items have shown that the local search approach outperforms the other methods. However, based on this evaluation, we cannot conclude that the degree of fulfillment of the requirements achieved by our method satisfies the end-user needs completely. To validate our approach and assess end-user satisfaction, we conducted a user evaluation study in which we compared six aspects of previews generated using our algorithm to human-made previews and to previews generated by subsampling. The results have shown that previews generated using our optimization-based approach are not as good as manually made previews, but have higher quality than previews created using subsample. The differences between the previews are statistically significant
Video Summarization Using Deep Neural Networks: A Survey
Video summarization technologies aim to create a concise and complete
synopsis by selecting the most informative parts of the video content. Several
approaches have been developed over the last couple of decades and the current
state of the art is represented by methods that rely on modern deep neural
network architectures. This work focuses on the recent advances in the area and
provides a comprehensive survey of the existing deep-learning-based methods for
generic video summarization. After presenting the motivation behind the
development of technologies for video summarization, we formulate the video
summarization task and discuss the main characteristics of a typical
deep-learning-based analysis pipeline. Then, we suggest a taxonomy of the
existing algorithms and provide a systematic review of the relevant literature
that shows the evolution of the deep-learning-based video summarization
technologies and leads to suggestions for future developments. We then report
on protocols for the objective evaluation of video summarization algorithms and
we compare the performance of several deep-learning-based approaches. Based on
the outcomes of these comparisons, as well as some documented considerations
about the suitability of evaluation protocols, we indicate potential future
research directions.Comment: Journal paper; Under revie
CHORUS Deliverable 2.2: Second report - identification of multi-disciplinary key issues for gap analysis toward EU multimedia search engines roadmap
After addressing the state-of-the-art during the first year of Chorus and establishing the existing landscape in
multimedia search engines, we have identified and analyzed gaps within European research effort during our second year.
In this period we focused on three directions, notably technological issues, user-centred issues and use-cases and socio-
economic and legal aspects. These were assessed by two central studies: firstly, a concerted vision of functional breakdown
of generic multimedia search engine, and secondly, a representative use-cases descriptions with the related discussion on
requirement for technological challenges. Both studies have been carried out in cooperation and consultation with the
community at large through EC concertation meetings (multimedia search engines cluster), several meetings with our
Think-Tank, presentations in international conferences, and surveys addressed to EU projects coordinators as well as
National initiatives coordinators. Based on the obtained feedback we identified two types of gaps, namely core
technological gaps that involve research challenges, and âenablersâ, which are not necessarily technical research
challenges, but have impact on innovation progress. New socio-economic trends are presented as well as emerging legal
challenges
Automatic movie analysis and summarisation
Automatic movie analysis is the task of employing Machine Learning methods to the
field of screenplays, movie scripts, and motion pictures to facilitate or enable various
tasks throughout the entirety of a movieâs life-cycle. From helping with making
informed decisions about a new movie script with respect to aspects such as its originality,
similarity to other movies, or even commercial viability, all the way to offering
consumers new and interesting ways of viewing the final movie, many stages in the
life-cycle of a movie stand to benefit from Machine Learning techniques that promise
to reduce human effort, time, or both. Within this field of automatic movie analysis,
this thesis addresses the task of summarising the content of screenplays, enabling users
at any stage to gain a broad understanding of a movie from greatly reduced data. The
contributions of this thesis are four-fold: (i)We introduce ScriptBase, a new large-scale
data set of original movie scripts, annotated with additional meta-information such as
genre and plot tags, cast information, and log- and tag-lines. To our knowledge, Script-
Base is the largest data set of its kind, containing scripts and information for almost
1,000 Hollywood movies. (ii) We present a dynamic summarisation model for the
screenplay domain, which allows for extraction of highly informative and important
scenes from movie scripts. The extracted summaries allow for the content of the original
script to stay largely intact and provide the user with its important parts, while
greatly reducing the script-reading time. (iii) We extend our summarisation model
to capture additional modalities beyond the screenplay text. The model is rendered
multi-modal by introducing visual information obtained from the actual movie and by
extracting scenes from the movie, allowing users to generate visual summaries of motion
pictures. (iv) We devise a novel end-to-end neural network model for generating
natural language screenplay overviews. This model enables the user to generate short
descriptive and informative texts that capture certain aspects of a movie script, such as
its genres, approximate content, or style, allowing them to gain a fast, high-level understanding
of the screenplay. Multiple automatic and human evaluations were carried
out to assess the performance of our models, demonstrating that they are well-suited
for the tasks set out in this thesis, outperforming strong baselines. Furthermore, the
ScriptBase data set has started to gain traction, and is currently used by a number of
other researchers in the field to tackle various tasks relating to screenplays and their
analysis