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Face Detection Starter App Using Haar Cascades

Added Jun 2025 3 design docs

Face detection is the classic first step into computer vision, and Haar cascade classifiers remain the clearest way to learn it: they are fast, run anywhere without a GPU, and expose tunable parameters whose effects are immediately visible. For beginners, building a working detector demystifies how machines locate objects in images at all, which matters in security applications from door cameras to visitor screening. The intern creates a Streamlit web application where users upload photographs and OpenCV's pre-trained Haar cascade classifier locates every face in the image. Detected faces are marked with bounding boxes drawn on the output image, along with detection details for each hit. The intern exposes the classifier's key parameters, such as scale factor and minimum neighbors, as interactive controls so users can watch how tightening or loosening them trades missed faces against false positives, and handles practical cases like group photos, varied image sizes, and pictures containing no faces at all. Through this project the intern learns the sliding-window detection paradigm that underpins classical object detection, gains confidence working with OpenCV and Python image arrays, and completes a demonstrable application that anchors the fundamentals needed before progressing to modern deep learning detectors.

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