Applications of Quick Response (QR) codes enable rich context interaction through creation of links between physical objects and internet resources. In spite of the widespread use of this kind of barcode, applications for visually impaired people and robots are not common because existing decoders assume that the symbol is properly framed during image acquisition. This project implements a two-stage component-based approach to perform accurate detection of QR code symbols in arbitrarily acquired images. In the first stage a cascade classifier to detect parts of the symbol is trained using the rapid object detection framework proposed by Viola-Jones. In the second stage, detected patterns are aggregated in order to evaluate if they are spatially arranged in a way that is geometrically consistent with the components of a QR code symbol. OpenCV 2.2+ is required.
