Automatically learning structural units in educational videos with the hierarchical hidden Markov models

In this paper we present a coherent approach using the hierarchical HMM with shared structures to extract the structural units that form the building blocks of an education/training video. Rather than using hand-crafted approaches to define the structural units, we use the data from nine training videos to learn the parameters of the HHMM, and thus naturally extract the hierarchy. We then study this hierarchy and examine the nature of the structure at different levels of abstraction. Since the observable is continuous, we also show how to extend the parameter learning in the HHMM to deal with continuous observations.

Neighborhood coherence and edge based approaches to film scene extraction

In order to enable high-level semantics-based video annotation and interpretation, we tackle the problem of automatic decomposition of motion pictures into meaningful story units, namely scenes. Since a scene is a complicated and subjective concept, we first propose guidelines from film production to determine when a scene change occurs in film. We examine different rules and conventions followed as part of Film Grammar to guide and shape our algorithmic solution for determining a scene boundary. Two different techniques are proposed as new solutions in this paper. Our experimental results on 10 full-length movies show that our technique based on shot sequence coherence performs well and reasonably better than the color edges-based approach.

Hierarchical representation for spatial knowledge

One of the fundamental issues in building autonomous agents is to be able to sense, represent and react to the world. Some of the earlier work [Mor83, Elf90, AyF89] has aimed towards a reconstructionist approach, where a number of sensors are used to obtain input that is used to construct a model of the world that mirrors the real world. Sensing and sensor fusion was thus an important aspect of such work. Such approaches have had limited success, and some of the main problems were the issues of uncertainty arising from sensor error and errors that accumulated in metric, quantitative models. Recent research has therefore looked at different ways of examining the problems. Instead of attempting to get the most accurate and correct model of the world, these approaches look at qualitative models to represent the world, which maintain relative and significant aspects of the environment rather than all aspects of the world. The relevant aspects of the world that are retained are determined by the task at hand which in turn determines how to sense. That is, task directed or purposive sensing is used to build a qualitative model of the world, which though inaccurate and incomplete is sufficient to solve the problem at hand. This paper examines the issues of building up a hierarchical knowledge representation of the environment with limited sensor input that can be actively acquired by an agent capable of interacting with the environment. Different tasks require different aspects of the environment to be abstracted out. For example, low level tasks such as navigation require aspects of the environment that are related to layout and obstacle placement. For the agent to be able to reposition itself in an environment, significant features of spatial situations and their relative placement need to be kept. For the agent to reason about objects in space, for example to determine the position of one object relative to another, the representation needs to retain information on relative locations of start and finish of the objects, that is endpoints of objects on a grid. For the agent to be able to do high level planning, the agent may need only the relative position of the starting point and destination, and not the low level details of endpoints, visual clues and so on. This indicates that a hierarchical approach would be suitable, such that each level in the hierarchy is at a different level of abstraction, and thus suitable for a different task. At the lowest level, the representation contains low level details of agent's motion and visual clues to allow the agent to navigate and reposition itself. At the next level of abstraction the aspects of the representation allow the agent to perform spatial reasoning, and finally the highest level of abstraction in the representation can be used by the agent for high level planning.

Horror film genre typing and scene labeling via audio analysis

We examine localised sound energy patterns, or events, that we associate with high level affect experienced with films. The study of sound energy events in conjunction with their intended affect enable the analysis of film at a higher conceptual level, such as genre. The various affect/emotional responses we investigate in this paper are brought about by well established patterns of sound energy dynamics employed in audio tracks of horror films. This allows the examination of the thematic content of the films in relation to horror elements. We analyse the frequency of sound energy and affect events at a film level as well as at a scene level, and propose measures indicative of the film genre and scene content. Using 4 horror, and 2 non-horror movies as experimental data we establish a correlation between the sound energy event types and horrific thematic content within film, thus enabling an automated mechanism for genre typing and scene content labeling in film.

Identifying film takes for cinematic analysis

In this paper, we focus on the ‘reverse editing’ problem in movie analysis, i.e., the extraction of film takes, original camera shots that a film editor extracts and arranges to produce a finished scene. The ability to disassemble final scenes and shots into takes is essential for nonlinear browsing, content annotation and the extraction of higher order cinematic constructs from film. In this work, we investigate agglomerative hierachical clustering methods along with different similarity metrics and group distances for this task, and demonstrate our findings with 10 movies.

The idea of Rome in Fascist art and architecture : the decorative program of the Palazzo dei Congressi in EUR, Rome

This paper engages with the notion of interspace by examining an understudied and unpublished cycle of mosaics and frescoes destined for the main hall of the Palazzo dei Congressi in Rome’s south-western suburb of EUR, a major building project by Roman architect Adalberto Libera. It first provides a socio-historical and aesthetic background to the building of EUR as Rome’s international exposition of 1942, which aimed to celebrate the achievements of Italian (and fascist) civilisation. It then focuses on the concept of Romanità (or Roman-ness) as a mythical and idealised past that was engaged on a number of levels as a teleological foundation for the advent (and eternity) of fascist rule. This past was adopted, interpreted and made manifest at the urban scale in the master plan of EUR, at the architectural scale in the buildings and at the interior scale in the decorative programs incorporated in each. It argues that the Palazzo dei Congressi allows us to gain further insight into the notion of interspace as it exemplifies this on a number of physical, symbolic and temporal levels. Physically, in the urban space, architectural form and interiors; symbolically, in the content and compositional layout of the mosaics; and temporally, in the use of historical elision and conflation between mythical pasts and idealised present.

Spatial reasoning by active observation

The problem of deriving spatial relationships between objects in general requires high lever' abstract representation, and it would pose difficulties even for human observer. Based on a formalism for spatial layouts proposed earlier, we present methods for deducing spatial relations between objects by an active, sighted agent in a large-scale environment. The deduction of spatial relations is based on simple visual clues, and thus this technique is more feasible than schemes that rely on complex object recognition.

Video indexing by spatial representation

Recent approaches to video indexing and retrieval are either pixel-oriented or object-oriented. While the former approaches focus on motion and changes thereto, the latter focus on spatial relations among objects in the scene. In this paper, a spatial knowledge representation technique combining both approaches is proposed. This representation supplements the spatial knowledge of visual objects with information about their pixel positions in the video frame. It provides a practical way to construct video indices, enabling searching for and retrieval of video sequences that contain motion as well as sparsely disjoint objects

Automated film rhythm extraction for scene analysis

This paper examines film rhythm, an important expressive element in motion pictures, based on our ongoing study to exploit film grammar as a broad computational framework for the task of automated film and video understanding. Of the many, more or less elusive, narrative devices contributing to film rhythm, this paper discusses motion characteristics that form the basis of our analysis, and presents novel computational models for extracting rhythmic patterns induced through a perception of motion. In our rhythm model, motion behaviour is classified as being either nonexistent, fluid or staccato for a given shot. Shot neighbourhoods in movies are then grouped by proportional makeup of these motion behavioural classes to yield seven high-level rhythmic arrangements that prove to be adept at indicating likely scene content (e.g. dialogue or chase sequence) in our experiments. Underlying causes for this level of codification in our approach are postulated from film grammar, and are accompanied by detailed demonstration from real movies for the purposes of clarification.

Deduction of high level spatial relations

The problem of deriving spatial relationships between objects in general requires high level abstract representation, and it would pose difficulties even for human observer. Based on a formalism for spatial layouts proposed earlier [KiV92, VeK921, we present methods for deducing high level spatial relations between objects by an active, sighted agent in a large-scale environment. The deduction of spatial relations is based on simple visual clues, and thus this technique is more feasible than schemes that rely on complex object recognition.

Detecting indexical signs in film audio for scene interpretation

In this paper, we study the sound tracks in films and their indexical semiotic usage by developing a classification system that detects complex sound scenes and their constituent sound events in cinema. We investigate two main issues in this paper: Determination of what constitutes the presence of a high level sound scene and inferences about the thematic content of the scene that can be drawn from this presence, and classification of environmental sounds in the audio track of the scene, to assist in the automatic detection of the high level scene. Experiments with our classification system on pure sounds resulted in a correct event classification rate of 88.9%. When the audio content of a number of film scenes was examined, though a lower accuracy resulted with sound event detection due to the presence of mixed sounds, the film audio samples were generally classified with the correct high-level sound scene label, enabling correct inferences about the story content of the scenes.

Determining dramatic intensification via flashing lights in movies

Movie directors and producers worldwide, in their quest to narrate a good story that warrants repeated audience viewing, use many cinematic elements to intensify and clarify the viewing experience. One such element that directors manipulate is lighting. In this paper we examine one aspect of lighting, namely flashing lights, and its role as an intensifier of dramatic effects in film. We present an algorithm for robust extraction of flashing lights and a simple mechanism to group detected flashing lights into flashing light scenes and analyze the role of these segments in story narration. In addition, we demonstrate how flashing lights detection can improve the performance of shot-based video segmentation. Experiments on a number of video sequences extracted from real movies yields good results. Our technique detects 90.4% of flashing lights. The detected flashing lights correctly eliminates 92.7% of false cuts in these sequences. In addition, data support is compiled to demonstrate the association between flashing light scenes and certain dramatic intensification events such as supernatural power, crisis or excitement.

Analysis of the current distribution in an aluminum electrolysis cell with copper collector-bar cathode assembly

Understanding the magneto-hydrodynamic forces generated due to the external magnetic field and current density distribution within the cell (current in cell linings) is important in the optimization of cell dynamics. It is well documented that these factors play a crucial role in establishing the metal-pad stability of the cell. Conventional cells use the cathode-collector-bar assembly to carry the current through molten aluminium, the cathode and the steel collector-bar to nearest external bus. The electrical conductivity of the steel is so poor relative to the molten aluminium that the outer third of the collector bar carries the maximum load, which in turn increases the horizontal components of the current within the cell. Previous studies have modelled improvement in the cell instability through external magnetic compensation by redistributing current in the cathode busbar. Very little to date has been published on work to improve the current distribution within the cell. In this work, the current distribution in an aluminium electrolysis cell with copper collector-bar was predicted using finite element modelling. A 2D cross-section of a commercial cell was used under steady conditions of electrical fields in anode, electrolyte, molten aluminium and copper cathode-assembly. Different shapes and sizes of the cathode assembly are also considered to optimise the distribution of current throughout the cathode lining. The findings indicated that the copper-bar of similar size to steel could save voltage up to 150 mV. There is a reduction of more than 70% in peak current density value due to the copper inserts. The predicted trends of current distribution show a good agreement with previously published data.

Costco and the Aussie shopper : a case study of the market entry of an international retailer

Retailing is a globalised industry, yet retailers must respond to local shopping habits if they are to be perceived as legitimate by the host country customers. However, some retailers may be unable or unwilling to respond to all customer requirements. Costco, the membership warehouse club retailer, has been successful in its international expansion efforts, establishing its first Australian store in Melbourne in 2009. In the first 12 months of operation, the store became one of Costco's top five stores in the world. We investigated this success by focussing on the customer and used institutional theory to analyse what concessions were made by the customer and the company. Data were collected from consumer interviews, site visits and secondary media and industry sources. Analysis revealed negotiations based on the rejection, acceptance or adaptation of the regulative, normative and cultural cognitive aspects of the Australian shopper and the Costco business model. Customers made concessions to accommodate the new business model, and Costco responded to entrenched Australian shopping habits. This case is the first to explore the outcome of retail internationalisation from the customers' perspective, revealing the concept of mutual concessions. The interaction and subsequent adaptation by both customer and retailer have resulted in the institutionalisation of new shopping norms in the host country and success for the international retailer.

Discrete event simulation enabled high level emulation of a distribution centre

Emulation facilitates the testing of control systems through the use of a simulation model. Typically emulation has focused on low level control, to ensure that resources within a system are commissioned correctly. Higher level control that deals with complex issues such as throughput, in-system time and stacking, has not received as much attention. In this paper, a higher level agent-based emulation framework was proposed. Then an emulation model for a distribution centre is described that can test distribution centre level algorithms directly. This methodology also allows playback of real world operations, making it an ideal tool to analyse problems with performance of commissioned systems.