arXiv subjects

Jaspal Subhlok

Publications and source records attributed to Jaspal Subhlok.

5 recordsLinked to original sources

arXiv2026

Cite or Decline: A Strict Course-Grounded Chatbot for STEM Lecture Videos

Recorded lecture videos, often enhanced with search and summarization features, are a standard study resource. However, students cannot easily ask course specific questions or verify answers against an instructor's lecture. We report a semester-long deployment of VideoPoints platform with a retrieval-augmented chatbot that answers from course lecture materials and returns timestamped citations. The chatbot retrieves only from the active course, uses chapter summaries to guide transcript ranking, and returns clickable timestamped citations. Students used it for quick lookups and exam review. Across 833 messages, 70.5% included citations, none crossed a course boundary, and when no lecture evidence matched, the chatbot usually declined rather than answering. Among the users, citations were the most consistently useful feature, while practice-question generation was the strongest unmet request. We also evaluated the design on the real-world test split of EduVidQA, a public multimodal benchmark for lecture-video question answering. Our design improved correct-lecture retrieval by 6.3 percentage points over dense-only retrieval. Together, the results show that effective deployment depends on course isolation, supported citations, and alignment with students' study practices.

cs.CL↗

arXiv2025

Visual Content Detection in Educational Videos with Transfer Learning and Dataset Enrichment

Video is transforming education with online courses and recorded lectures supplementing and replacing classroom teaching. Recent research has focused on enhancing information retrieval for video lectures with advanced navigation, searchability, summarization, as well as question answering chatbots. Visual elements like tables, charts, and illustrations are central to comprehension, retention, and data presentation in lecture videos, yet their full potential for improving access to video content remains underutilized. A major factor is that accurate automatic detection of visual elements in a lecture video is challenging; reasons include i) most visual elements, such as charts, graphs, tables, and illustrations, are artificially created and lack any standard structure, and ii) coherent visual objects may lack clear boundaries and may be composed of connected text and visual components. Despite advancements in deep learning based object detection, current models do not yield satisfactory performance due to the unique nature of visual content in lectures and scarcity of annotated datasets. This paper reports on a transfer learning approach for detecting visual elements in lecture video frames. A suite of state of the art object detection models were evaluated for their performance on lecture video datasets. YOLO emerged as the most promising model for this task. Subsequently YOLO was optimized for lecture video object detection with training on multiple benchmark datasets and deploying a semi-supervised auto labeling strategy. Results evaluate the success of this approach, also in developing a general solution to the problem of object detection in lecture videos. Paper contributions include a publicly released benchmark of annotated lecture video frames, along with the source code to facilitate future research.

cs.CV↗

arXiv2025

Lecture Video Visual Objects (LVVO) Dataset: A Benchmark for Visual Object Detection in Educational Videos

We introduce the Lecture Video Visual Objects (LVVO) dataset, a new benchmark for visual object detection in educational video content. The dataset consists of 4,000 frames extracted from 245 lecture videos spanning biology, computer science, and geosciences. A subset of 1,000 frames, referred to as LVVO_1k, has been manually annotated with bounding boxes for four visual categories: Table, Chart-Graph, Photographic-image, and Visual-illustration. Each frame was labeled independently by two annotators, resulting in an inter-annotator F1 score of 83.41%, indicating strong agreement. To ensure high-quality consensus annotations, a third expert reviewed and resolved all cases of disagreement through a conflict resolution process. To expand the dataset, a semi-supervised approach was employed to automatically annotate the remaining 3,000 frames, forming LVVO_3k. The complete dataset offers a valuable resource for developing and evaluating both supervised and semi-supervised methods for visual content detection in educational videos. The LVVO dataset is publicly available to support further research in this domain.

cs.CV↗

arXiv2020

Visual Summarization of Lecture Video Segments for Enhanced Navigation

Lecture videos are an increasingly important learning resource for higher education. However, the challenge of quickly finding the content of interest in a lecture video is an important limitation of this format. This paper introduces visual summarization of lecture video segments to enhance navigation. A lecture video is divided into segments based on the frame-to-frame similarity of content. The user navigates the lecture video content by viewing a single frame visual and textual summary of each segment. The paper presents a novel methodology to generate the visual summary of a lecture video segment by computing similarities between images extracted from the segment and employing a graph-based algorithm to identify the subset of most representative images. The results from this research are integrated into a real-world lecture video management portal called Videopoints. To collect ground truth for evaluation, a survey was conducted where multiple users manually provided visual summaries for 40 lecture video segments. The users also stated whether any images were not selected for the summary because they were similar to other selected images. The graph based algorithm for identifying summary images achieves 78% precision and 72% F1-measure with frequently selected images as the ground truth, and 94% precision and 72% F1-measure with the union of all user selected images as the ground truth. For 98% of algorithm selected visual summary images, at least one user also selected that image for their summary or considered it similar to another image they selected. Over 65% of automatically generated summaries were rated as good or very good by the users on a 4-point scale from poor to very good. Overall, the results establish that the methodology introduced in this paper produces good quality visual summaries that are practically useful for lecture video navigation.

cs.CV↗

arXiv2016

Checkpointing to minimize completion time for Inter-dependent Parallel Processes on Volunteer Grids

Volunteer computing is being used successfully for large scale scientific computations. This research is in the context of Volpex, a programming framework that supports communicating parallel processes in a volunteer environment. Redundancy and checkpointing are combined to ensure consistent forward progress with Volpex in this unique execution environment characterized by heterogeneous failure prone nodes and interdependent replicated processes. An important parameter for optimizing performance with Volpex is the frequency of checkpointing. The paper presents a mathematical model to minimize the completion time for inter-dependent parallel processes running in a volunteer environment by finding a suitable checkpoint interval. Validation is performed with a sample real world application running on a pool of distributed volunteer nodes. The results indicate that the performance with our predicted checkpoint interval is fairly close to the best performance obtained empirically by varying the checkpoint interval.

cs.DC↗