detectface_2.py

pythondetectface_2.py

#-*- coding: utf-8 -*-
#!/usr/bin/env python

'''
face detection using haar cascades

USAGE:
    facedetect.py [--cascade <cascade_fn>] [--nested-cascade <cascade_fn>] [<video_source>]
'''

# Python 2/3 compatibility
from __future__ import print_function

import numpy as np
import cv2 as cv
from pprint import pprint

# local modules
from video import create_capture
from common import clock, draw_str

mosaic_rate = 30


def detect(img, cascade):
    rects = cascade.detectMultiScale(img, scaleFactor=1.3, minNeighbors=4, minSize=(30, 30),
                                     flags=cv.CASCADE_SCALE_IMAGE)
    if len(rects) == 0:
        return []

    # rects[:,2:] += rects[:,:2]
    return rects

def draw_rects(img, rects, color):
    for x1, y1, x2, y2 in rects:
        cv.rectangle(img, (x1, y1), (x2, y2), color, 2)

if __name__ == '__main__':
    import sys, getopt
    print(__doc__)

    args, video_src = getopt.getopt(sys.argv[1:], '', ['cascade=', 'nested-cascade='])
    try:
        video_src = video_src[1]
    except:
        video_src = 0
    args = dict(args)
    cascade_fn = args.get('--cascade', "../../data/haarcascades/haarcascade_frontalface_alt.xml")
    nested_fn  = args.get('--nested-cascade', "../../data/haarcascades/haarcascade_eye.xml")

    cascade = cv.CascadeClassifier(cascade_fn)
    nested = cv.CascadeClassifier(nested_fn)

    cam = create_capture(video_src, fallback='synth:bg=../data/lena.jpg:noise=0.05')

    while True:
        ret, img = cam.read()
        gray = cv.cvtColor(img, cv.COLOR_BGR2GRAY)
        gray = cv.equalizeHist(gray)

        t = clock()
        rects = detect(gray, cascade)
        vis = img.copy()

        for (x, y, w, h) in rects:
            # print ("detect face rects : {:d}, {:d}, {:d}, {:d}".format(x,y,w,h))
            face_img = img[y:y+h, x:x+w]
            face_img = cv.resize(face_img, (w//mosaic_rate, h//mosaic_rate))
            face_img = cv.resize(face_img, (w, h), interpolation=cv.INTER_AREA)
            vis[y:y+h, x:x+w] = face_img


        dt = clock() - t
        draw_str(vis, (20, 20), 'time: %.1f ms' % (dt*1000))
        cv.imshow('facedetect', vis)

        if cv.waitKey(5) == 27:
            break
    cv.destroyAllWindows()