- Research Article
- 10.1063/1.2405544
Focus on software
- Aug 01, 2006
- Physics Today
- Lawrence G Rubin
Focus on software
Large-scale audiovisual data that measure group learning are time consuming to collect and analyze. As an initial step towards scaling qualitative classroom observation, we qualitatively coded classroom video using an established coding scheme with and without its audio cues. We find that interrater reliability is as high when using visual data only—without audio—as when using both visual and audio data to code. Also, interrater reliability is high when comparing use of visual and audio data to visual-only data. We see a small bias to code interactions as group discussion when visual and audio data are used compared with video-only data. This work establishes that meaningful educational observation can be made through visual information alone. Further, it suggests that after initial work to create a coding scheme and validate it in each environment, computer-automated visual coding could drastically increase the breadth of qualitative studies and allow for meaningful educational analysis on a far greater scale.
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Focus on software
Focus on software
What are Visual Data and What Utility do they have in Science Education?
Visual data differs from visual information since it must be recorded, analyzed, and manipulated in some manner, whereas visual information is primarily sensory input. Our environment is constantly infused with visual inputs, and it is sometimes difficult to make sense of them or to determine how best to deal with them for instructional purposes and capitalize on their power as visual data. This article briefly examines how visual data can be used in a variety of disciplines including art, language arts/reading, mathematics, social studies, and science. The utility and use of visual data in science education is a particular focus of the paper, along with discussion about its relevance in today’s educational environment.
Read moreVisual and corresponding tactile dataset of flexible material for robots and cross modal perception
Humans primarily understand the world around them through visual perception and touch. As a result, visual and tactile information play crucial roles in the interaction between humans and their environment. In order to establish a correlation between what is seen and what is felt on the same object, particularly on flexible objects (such as textile, leather, skin etc.) which humans often access by touch to cooperatively determine their quality, the need for a new dataset that includes both visual and tactile information arises. This has motivated us to create a dataset that combines visual images and corresponding tactile data to explore the potential of cross-modal data fusion. We have chosen leather as our object of focus due to its widespread usage in everyday life. The dataset we propose consists of visual images depicting leather in various colours and displaying defects, alongside corresponding tactile data collected from the same region of the leather. Notably, the tactile data comprises components along the X, Y, and Z axes. To effectively demonstrate the relationship between visual and tactile data on the same object region, the tactile data is aligned with the visual data and visualized through interpolation. Considering the potential applications in computer vision, we have manually labelled the defect regions in each visual-tactile sample. Ultimately, the dataset comprises a total of 687 records. Each sample includes visual images, image representations of the tactile data (referred to as tactile images for simplicity), and segmentation images highlighting the defect regions, all with the same resolution.
Read moreAudio-Visual Speech Recognition Using MPEG-4 Compliant Visual Features
We describe an audio-visual automatic continuous speech recognition system, which significantly improves speech recognition performance over a wide range of acoustic noise levels, as well as under clean audio conditions. The system utilizes facial animation parameters (FAPs) supported by the MPEG-4 standard for the visual representation of speech. We also describe a robust and automatic algorithm we have developed to extract FAPs from visual data, which does not require hand labeling or extensive training procedures. The principal component analysis (PCA) was performed on the FAPs in order to decrease the dimensionality of the visual feature vectors, and the derived projection weights were used as visual features in the audio-visual automatic speech recognition (ASR) experiments. Both single-stream and multistream hidden Markov models (HMMs) were used to model the ASR system, integrate audio and visual information, and perform a relatively large vocabulary (approximately 1000 words) speech recognition experiments. The experiments performed use clean audio data and audio data corrupted by stationary white Gaussian noise at various SNRs. The proposed system reduces the word error rate (WER) by 20% to 23% relatively to audio-only speech recognition WERs, at various SNRs (0–30 dB) with additive white Gaussian noise, and by 19% relatively to audio-only speech recognition WER under clean audio conditions.
Read moreThe Audio-Visual Arabic Dataset for Natural Emotions
Emotions are a crucial aspect of human life and the researchers have tried to build an automatic emotion recognition system that helps to provide important real-world applications. The psychologists have shown that emotions differ across culture, considering this fact, we provide and describe the first audio-visual Arabic emotional dataset which called (AVANEmo). In this work we aim to fill the gap between studies of emotion recognition for Arabic content and other languages by provided an Arabic dataset which is a major and fundamental part of build emotion recognition application. Our dataset contains 3000 clips for video and audio data, and it covers six basic emotional labels (Happy, Sad, Angry, Surprise, Disgust, Neutral). Also, we provide some baseline experiments to measure the primitive performance for automated audio and visual emotion recognition application using the AVANEmo dataset. The best accuracy that we achieved was 54.5% and 57.9% using the audio and visual data respectively. The data will be available for distribution to researchers.
Read moreBecoming Racially Literate About Data and Data-Literate About Race: Data Visualizations in the Classroom as a Site of Racial-Ideological Micro-Contestations
ABSTRACTData visualizations are now commonplace in the public media. The ability to interpret and create such visualizations, as a form of data literacy, is increasingly important for democratic participation. Yet, the cross-disciplinary knowledge and skills needed to produce and use data visualizations and to develop data literacy are not fluidly integrated into traditional K–12 subject areas. In this article, we nuance and complicate the push for data literacy in STEM reform efforts targeting youth of color. We explore a curricular reform project that integrated explicit attention to issues pertaining to the collection, analysis, interpretation, representation, visualization, and communication of data in an introductory computer science class. While the study of data in this unit emphasized viewing and approaching data in context, neither the teacher nor the students were supported in negotiating the racialized context of data that emerged in classroom discussions. To better understand these dynamics, we detail the construct of racial literacy and develop an interpretative framework of racial-ideological micro-contestations. Through an in-depth analysis of a classroom interaction using this framework, we explore how contestations about race can emerge when data visualizations from the public media are incorporated into STEM learning precisely because the contexts of data are often racialized. We argue that access to learning about data visualization, without a deep interrogation of race and power, can be counterproductive and that efforts to develop authentic data literacy require the concomitant development of racial literacy.
Read moreRETRACTED ARTICLE: Content based video retrieval system based on multimodal feature grouping by KFCM clustering algorithm to promote human–computer interaction
Content Based Video Retrieval (CBVR) is so popular these days, because of the increased utilization of video based analytical systems. Video based analytics is quite effective than image analysis, as a series of actions are captured by the video. This ends up with better decision making ability. The CBVR systems play an important role in boosting the human–computer interaction. This paper presents a multimodal CBVR that takes both the visual and audio information into account for retrieving relevant videos to the user. Two modules are employed by this work to deal with video and audio data. The video data is processed to detect the significant frame from shots and is achieved by Lion Optimization Algorithm (LOA). The features are extracted from the visual data and with respect to the audio data, MHEC and LPCC features are extracted. The extracted features are clustered by Kernelized Fuzzy C Mean (KFCM) algorithm. Finally, the feature database is formed and is utilized in the query matching process during the testing phase. The performance of the proposed work is tested in terms of precision, recall, F-measure and time consumption rates. The proposed CBVR system proves better performance than the existing approaches and is evident through attained results.
Read moreCross-Domain Deep Feature Combination for Bird Species Classification with Audio-Visual Data
In recent decade, many state-of-the-art algorithms on image classification as well as audio classification have achieved noticeable successes with the development of deep convolutional neural network (CNN). However, most of the works only exploit single type of training data. In this paper, we present a study on classifying bird species by exploiting the combination of both visual (images) and audio (sounds) data using CNN, which has been sparsely treated so far. Specifically, we propose CNN-based multimodal learning models in three types of fusion strategies (early, middle, late) to settle the issues of combining training data cross domains. The advantage of our proposed method lies on the fact that We can utilize CNN not only to extract features from image and audio data (spectrogram) but also to combine the features across modalities. In the experiment, we train and evaluate the network structure on a comprehensive CUB-200-2011 standard data set combing our originally collected audio data set with respect to the data species. We observe that a model which utilizes the combination of both data outperforms models trained with only an either type of data. We also show that transfer learning can significantly increase the classification performance.
Read moreEnhancing Emotion Recognition through Multimodal Systems and Advanced Deep Learning Techniques
Emotion detection, hence, is an important step toward making human-computer interaction a more enhanced process, where systems are made capable of identifying and responding to the emotional state of users. In fact, multimodal emotion detection systems in which both auditory and visual information are fused are emerging, and these approaches toward expressive emotional states are complementary and robust. Multimodal systems enhance the quality of interacting and, through many applications, can diagnose emotional disorders, monitor automotive safety, and improve human-robot interactions. In nature, the high-dimensional space and dynamic threats have resulted in obtaining low accuracy and high computational cost in applying the traditional models based on single-modality data. On the other hand, multimodal systems explore the synergy between audio and visual data, giving better performance and higher accuracy in inferring subtle emotional expressions. The latest improvement was done on these systems using recent advancements in transfer learning and deep learning techniques.That being said, this research Proposal devises a multimodal emotion recognition system integrating speech and face information through transfer learning for improved accuracy and robustness. Serving this purpose, the objectives of this research entail the effective comparison among different transfer-learning strategies, including the impact of pre-trained models in speech-based emotion recognition, and to introduce the role of voice activity detection in the process. Advanced neural network architectures like Spatial Transformer Networks and bidirectional LSTM in facial emotion recognition will also be tested. Early and late fusion strategies will also be used to find the best strategy for combining speech and facial data.This research will target several challenges that involve the complexity of data, balancing of the model performance-robustness balance, computational limitations, and standardization of evaluations in developing a working and robust emotion recognition system to enhance digital interaction and apply in practical areas. The goal is to create a system that oversteps the limitation of single-modality models through state-of-the-art advances in deep learning, as well as front-line improvements in transfer learning, in the manner of emotion detection performance.
Read moreSpeaker selection and tracking in a cluttered environment with audio and visual information
Presented in this paper is a data association method using audio and visual data which localizes targets in a cluttered environment and detects who is speaking to a robot. A particle filter is applied to efficiently select the optimal association between the target and the measurements. State variables are composed of target positions and speaking states. To update the speaking state, we first evaluate the incoming sound signal based on cross-correlation and then calculate a likelihood from the audio information. The visual measurement is used to find an optimal association between the target and the observed objects. The number of targets that the robot should interact with is updated from the existence probabilities and associations. Experimental data were collected beforehand and simulated on a computer to verify the performance of the proposed method applied to the speaker selection problem in a cluttered environment. The algorithm was also implemented in a robotic system to demonstrate reliable interactions between the robot and speaking targets.
Read moreAudio-video fusion strategies for active speaker detection in meetings
Meetings are a common activity in professional contexts, and it remains challenging to endow vocal assistants with advanced functionalities to facilitate meeting management. In this context, a task like active speaker detection can provide useful insights to model interaction between meeting participants. Detection of the active speaker can be performed using only video based on the movements of the participants of a meeting. Depending on the assistant design and each participant position regarding the device, active speaker detection can benefit from information coming from visual and audio modalities. Motivated by our application context related to advanced meeting assistant, we want to combine audio and visual information to achieve the best possible performance. In this paper, we propose two different types of fusion (naive fusion and attention-based fusion) for the detection of the active speaker, combining two visual modalities and an audio modality through neural networks. In addition, the audio modality is mainly processed using neural networks. For comparison purpose, classical unsupervised approaches for audio feature extraction are also used. We expect visual data centered on the face of each participant to be very appropriate for detecting voice activity, based on the detection of lip and facial gestures. Thus, our baseline system uses visual data (video) and we chose a 3D Convolutional Neural Network (CNN) architecture, which is effective for simultaneously encoding appearance and movement. To improve this system, we supplemented the visual information by processing the audio stream with a CNN or an unsupervised speaker diarization system. We have further improved this system by adding visual modality information using motion through optical flow. We evaluated our proposal with a public and state-of-the-art benchmark: the AMI corpus. We analysed the contribution of each system to the merger carried out in order to determine if a given participant is currently speaking. We also discussed the results we obtained. Besides, we have shown that, for our application context, adding motion information greatly improves performance. Finally, we have shown that attention-based fusion improves performance while reducing the standard deviation.
Read moreA method of multirate sensor fusion for target tracking and localization using extended Kalman Filter
This paper presents a method of target tracking and localization for surveillance vehicle with visual-inertia sensor-fusion using extended Kalman Filter (EKF). In this application, the visual information is obtained using rotating camera and laser range finder. The visual data are used to incorporate inertial measuring unit (IMU) in the determination of position and velocity of the surveillance vehicle and also used to determine the position and velocity of the target which is moving with respect to the moving surveillance vehicle. As the camera is rotating, the visual data is available in aperiodic intervals (i.e., the target/landmark is presented in the field of view). Here, an EKF is used as state estimator to describe the position and velocity of the surveillance vehicle from the noisy, multi-rate measurements given by the sensing system. The prediction and measurement models are developed for the movement of vehicle and sensing system. The numerical simulation is used to investigate the performance of the proposed method. The simulation results show that proposed method can be used for target tracking and is able to improve the localization performance.
Read moreSpecial Issue on Machine Learning Approaches in Big Data Visualization
The articles in this special section focus on analytic rendering and hardware-accelerated simulation for scientific applications. Data visualization is now one of the cornerstones of data science, turning the abundance of big data being produced through modern systems into actionable knowledge. Data visualization in the big data era raises the need to co-design and more closely align the underlying data management systems with the user-oriented techniques that state-of-the-art visualization systems now offer. In addition, the tight integration of suitable machine learning approaches with data visualization and their control by users-in-theloop promises to enhance scalability, effectiveness, and adaptivity of the interactive visual data analysis process. This special issue attracted and publishes research work on multidisciplinary research areas from the human–computer interaction, computer graphics, and data management communities.
Read moreVAD-CLVA: Integrating CLIP with LLaVA for Voice Activity Detection
Voice activity detection (VAD) is the process of automatically determining whether a person is speaking and identifying the timing of their speech in an audiovisual data. Traditionally, this task has been tackled by processing either audio signals or visual data, or by combining both modalities through fusion or joint learning. In our study, drawing inspiration from recent advancements in visual-language models, we introduce a novel approach leveraging Contrastive Language-Image Pretraining (CLIP) models. The CLIP visual encoder analyzes video segments focusing on the upper body of an individual, while the text encoder processes textual descriptions generated by a Generative Large Multimodal Model, i.e., the Large Language and Vision Assistant (LLaVA). Subsequently, embeddings from these encoders are fused through a deep neural network to perform VAD. Our experimental analysis across three VAD benchmarks showcases the superior performance of our method compared to existing visual VAD approaches. Notably, our approach outperforms several audio-visual methods despite its simplicity and without requiring pretraining on extensive audio-visual datasets.
Read moreInteractive visualization and topology-based analysis of large-scale time-varying remote-sensing data: challenges and opportunities
<p>Over the last few years, the amount of large and complex data in the public domain has increased enormously and new challenges arose in the representation, analysis and visualization of such data. Considering the number of space missions that provided and will provide remote sensing data, there is still the need of a system that can be dispatched in several remote repositories and being accessible from a single client of commodity hardware.</p><p>To tackle this challenge, at the DLR Institute for Software Technology we have defined a dual backend frontend system, enabling the interactive analysis and visualization of large-scale remote sensing data. The basis for all visualization and interaction approaches is CosmoScout VR, a visualization tool developed internally at DLR, and publicly available on Github, that allows the visualization of complex planetary data and large simulation data in real-time. The dual component of this system is based on an MPI framework, called Viracocha, that enables the analysis of large data remotely, and allows the efficient network usage about sending compact and partial results for interactive visualization in CosmoScout as soon as they are computed.</p><p>A node-based interface is defined within the visualization tool, and this lets a domain expert to easily define customized pipelines for processing and visualizing the remote data. Each “node” of this interface is either linked with a feature extraction module, defined in Viracocha, or to a rendering module defined directly in CosmoScout. Being this interface completely customizable by a user, multiple pipelines can be defined over the same dataset to enhance even more the visualization feedback for analysis purposes.</p><p>Being an ongoing project, on top of these tools, as a novel strategy in EO data processing and visualization, we plan to define and implement strategies based on Topological Data Analysis (TDA). TDA is an emerging set of technique for processing the data considering its topological features. These include both the geometric information associated to a point, as well all the non-geometric scalar values, like temperature and pressure, to name a few, that can be captured during a monitoring mission. One of the major theories behind TDA is Discrete Morse Theory, that, given a scalar value, is used to define a gradient on such function, extract the critical points, identify the region-of-influence of each critical point, and so on. This strategy is parameter free and enables a domain scientist to process large datasets without a prior knowledge of it.</p><p>An interesting research question, that it will be investigated during this project is the correlation of changes of critical points at different time steps, and the identification of deformation (or changes) across time in the original dataset.</p>
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