With the growing popularity of mobile devices that have built-in cameras, capturing images has become a trivial job for ordinary people, who share the images with their friends or the public online. However, such digital images are often taken without the consent of some photographed persons, hence leading to privacy concerns. In this paper, we propose iRyP, a purely edge-based privacy-respecting system for mobile cameras. In order to meet the requirements of efficiency and usability, we propose to piggyback privacy policies in the advertising messages of Bluetooth Low Energy (BLE), which has been widely deployed in most mobile devices. As such, privacy policies of people in a photo view can be delivered timely and automatically. Moreover, we propose to use a perceptual hashing algorithm for fast face matching. To improve detection accuracy, we also design several new techniques for face-related image processing. We implement and evaluate a prototype system purely based on the Android platform. Our experiments show that iRyP can meet our design requirements and is practical and ready to use.