LectureSync: Slide-Grounded Lecture Q&A Without an Aligner Service

LectureSync is presented as a Pixeltable-based application for turning lecture videos and slide PDFs into searchable, citeable learning materials without separately managing PDF extraction, video frame sampling, transcription, and multiple vector databases. A central Lectures table stores each lecture’s metadata, video, and slides, while derived Slides and Frames views split PDFs into page-level text and images and sample video at one frame per second; embeddings support semantic slide-text retrieval and visual search across slide images and frames. Audio is extracted and transcribed with Whisper, and a retrieval query returns relevant slide content alongside the lecture transcript, after which a generative model can produce an answer grounded in those sources. The approach emphasizes retrieving relevant pages and nearby speech rather than building a dedicated slide-to-timestamp alignment system, preserving slides as page-based units and retaining citations. It also describes deployment through the same application file on Pixeltable Cloud and distinguishes LectureSync from an LMS, videoconferencing platform, or grade-management system.

Use this post, company, and trend context to find content marketing opportunities, perform competitive analysis, or address product feature gaps via the Plushcap MCP server or the Plushcap API.