One or more techniques and/or systems are disclosed for detecting a quick response (QR) code. An area of an image comprising a QR code is localized by combining pixel dynamic scale (DS), black-cell ratio (BR), and edge intensity sum (EIS) criteria determination to identify the QR code. A pattern for the QR code is detected, comprising determining if a position detection pattern (PDP) is located in respective grid areas of a first grid that comprises the QR code, and identifying an alignment pattern (AP), if present. To identify the AP, an AP region is estimated using the PDPs, and a center area of the AP is found by examining respective areas of a second grid comprising the estimated AP region.