python build a snapchat filter

1import argparse
2
3import cv2
4from imutils.video import VideoStream
5from imutils import face_utils, translate, resize
6
7import time
8import dlib
9
10import numpy as np
11
12parser = argparse.ArgumentParser()
13parser.add_argument("-predictor", required=True, help="path to predictor")
14args = parser.parse_args()
15
16print("starting program.")
17print("'s' starts drawing eyes.")
18print("'r' to toggle recording image, and 'q' to quit")
19
20vs = VideoStream().start()
21time.sleep(1.5)
22
23# this detects our face
24detector = dlib.get_frontal_face_detector()
25# and this predicts our face's orientation
26predictor = dlib.shape_predictor(args.predictor)
27
28recording = False
29counter = 0
30
31class EyeList(object):
32    def __init__(self, length):
33        self.length = length
34        self.eyes = []
35
36    def push(self, newcoords):
37        if len(self.eyes) < self.length:
38            self.eyes.append(newcoords)
39        else:
40            self.eyes.pop(0)
41            self.eyes.append(newcoords)
42    
43    def clear(self):
44        self.eyes = []
45
46# start with 10 previous eye positions
47eyelist = EyeList(10)
48eyeSnake = False
49
50# get our first frame outside of loop, so we can see how our
51# webcame resized itself, and it's resolution w/ np.shape
52frame = vs.read()
53frame = resize(frame, width=800)
54
55eyelayer = np.zeros(frame.shape, dtype='uint8')
56eyemask = eyelayer.copy()
57eyemask = cv2.cvtColor(eyemask, cv2.COLOR_BGR2GRAY)
58translated = np.zeros(frame.shape, dtype='uint8')
59translated_mask = eyemask.copy()
60
61while True:
62    # read a frame from webcam, resize to be smaller
63    frame = vs.read()
64    frame = resize(frame, width=800)
65
66    # fill our masks and frames with 0 (black) on every draw loop
67    eyelayer.fill(0)
68    eyemask.fill(0)
69    translated.fill(0)
70    translated_mask.fill(0)
71
72    # the detector and predictor expect a grayscale image
73    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
74    rects = detector(gray, 0)
75
76    # if we're running the eyesnake loop (press 's' while running to enable)
77    if eyeSnake:
78        for rect in rects:
79            # the predictor is our 68 point model we loaded
80            shape = predictor(gray, rect)
81            shape = face_utils.shape_to_np(shape)
82
83            # our dlib model returns 68 points that make up a face.
84            # the left eye is the 36th point through the 42nd. the right
85            # eye is the 42nd point through the 48th.
86            leftEye = shape[36:42]
87            rightEye = shape[42:48]
88
89            # fill our mask in the shape of our eyes
90            cv2.fillPoly(eyemask, [leftEye], 255)
91            cv2.fillPoly(eyemask, [rightEye], 255)
92
93            # copy the image from the frame onto the eyelayer using that mask
94            eyelayer = cv2.bitwise_and(frame, frame, mask=eyemask)
95
96            # we use this to get an x and y coordinate for the pasting of eyes
97            x, y, w, h = cv2.boundingRect(eyemask)
98
99            # push this onto our list
100            eyelist.push([x, y])
101
102            # finally, draw our eyes, in reverse order
103            for i in reversed(eyelist.eyes):
104                # first, translate the eyelayer with just the eyes
105                translated1 = translate(eyelayer, i[0] - x, i[1] - y)
106                # next, translate its mask
107                translated1_mask = translate(eyemask, i[0] - x, i[1] - y)
108                # add it to the existing translated eyes mask (not actual add because of
109                # risk of overflow)
110                translated_mask = np.maximum(translated_mask, translated1_mask)
111                # cut out the new translated mask
112                translated = cv2.bitwise_and(translated, translated, mask=255 - translated1_mask)
113                # paste in the newly translated eye position
114                translated += translated1
115        # again, cut out the translated mask
116        frame = cv2.bitwise_and(frame, frame, mask=255 - translated_mask)
117        # and paste in the translated eye image
118        frame += translated
119
120    # display the current frame, and check to see if user pressed a key
121    cv2.imshow("eye glitch", frame)
122    key = cv2.waitKey(1) & 0xFF
123
124    if recording:
125        # create a directory called "image_seq", and we'll be able to create gifs in ffmpeg
126        # from image sequences
127        cv2.imwrite("image_seq/%05d.png" % counter, frame)
128        counter += 1
129
130    if key == ord("q"):
131        break
132
133    if key == ord("s"):
134        eyeSnake = not eyeSnake
135        eyelist.clear()
136
137    if key == ord("r"):
138        recording = not recording
139
140cv2.destroyAllWindows()
141vs.stop()
142