It is an interesting project using OpenCV
This code can apply glasses and mustache stickers to both images and live video-stream. Eyes and nose in an image or a captured frame from webcam are detected by corresponding haarcascade files. Using the positions and size of detected eyes and nose, the sticker images are resized and put on the original image at their respective locations.
This code is just a prototype having two stickers for now and it can be extended to more stickers also