【python】webカメラの映像に目の周囲だけ自動でモザイク

# -*- coding: utf-8 -*-
from face import Face
import cv2
from PIL import Image, ImageDraw
import numpy as np

def mosaic(img, ratio=0.1):
    small = cv2.resize(img, None, fx=ratio, fy=ratio, interpolation=cv2.INTER_NEAREST)
    return cv2.resize(small, img.shape[:2][::-1], interpolation=cv2.INTER_NEAREST)


# 左上の座標, 右下の座標
def mosaic_area(img, x1, y1, x2, y2, ratio=0.1):
    cp = img.copy()
    cp[y1:y2, x1:x2] = mosaic(cp[y1:y2, x1:x2], ratio)
    return cp


def main():
  face_detecter = Face()
  capture = cv2.VideoCapture(0)

  while(capture.isOpened()):
    ret, frame = capture.read()
    shape = face_detecter.get_face_point(frame)

    if not shape is None:
      frame = mosaic_area(frame, shape[17][0], shape[19][1], shape[26][0], shape[30][1], ratio=0.05)

    cv2.imshow('frame', frame)

    if cv2.waitKey(1) & 0xFF == ord('q'):
      break

  capture.release()
  cv2.destroyAllWindows()

if __name__ == "__main__":
  main()

# -*- coding: utf-8 -*-
import cv2
import dlib
from imutils import face_utils


class Face():
  def __init__(self):
    self.detector = dlib.get_frontal_face_detector() #顔検出器の呼び出し.ただ顔だけを検出する
    self.load_model()
  
  def load_model(self, path="./model/shape_predictor_68_face_landmarks.dat"):
    try:
      self.predictor = dlib.shape_predictor(path) #顔から目鼻などランドマークを出力する
    except Exception as e:
      raise ValueError('can not load predict model.')

  def get_face_point(self, frame):
    gray = cv2.cvtColor(frame, cv2.COLOR_RGB2GRAY) #gray scaleに変換する
    rects = self.detector(gray, 0) #grayから顔を検出

    if not rects:
      return 

    else:
      #顔が認識できればポイントを特定
      shape = self.predictor(gray, rects[0])
      shape = face_utils.shape_to_np(shape)
      return shape