trimming.py

 # Python 3

import cv2
import sys
import os

args = sys.argv
argc = len(args)

cascade_path = "/usr/local/Cellar/opencv3/3.1.0_3/share/OpenCV/haarcascades/haarcascade_frontalface_alt.xml"
#cascade_path = "/usr/local/Cellar/opencv3/3.1.0_3/share/OpenCV/haarcascades/haarcascade_frontalface_alt2.xml"
#cascade_path = "/usr/local/Cellar/opencv3/3.1.0_3/share/OpenCV/haarcascades/haarcascade_frontalface_default.xml"
#cascade_path = "/usr/local/Cellar/opencv3/3.1.0_3/share/OpenCV/haarcascades/haarcascade_eye.xml"

# 元画像から顔検知し枠で囲んだ画像を保存.
def saveDetectedFacesImg(image_path, facerect):

	color = (255, 255, 255)
	image = cv2.imread(image_path)
	path = os.path.splitext(image_path)

	for rect in facerect:
		cv2.rectangle(image, tuple(rect[0:2]),tuple(rect[0:2]+rect[2:4]), color, thickness=2)

	base = os.path.basename(image_path)
	filename, ext = os.path.splitext(base)
	cv2.imwrite("%s_detected.jpg"%(path[0]), image)

# 顔画像部分のみトリミングし保存.
def trimmingFaces(image_path, facerect):

	path = os.path.splitext(image_path)
	image = cv2.imread(image_path)

	i = 0
	for rect in facerect:
		x = rect[0]
		y = rect[1]
		width = rect[2]
		height = rect[3]
		dst = image[y:y+height, x:x+width]
		trimming_image = '%s_%s_%s'%(path[0],i,path[1])
		cv2.imwrite(trimming_image, dst)
		i += 1

if __name__ == "__main__":

	if(argc != 2):
		print('You donnot set parameter, please again.')
		quit()

	image_path = args[1]


	# read image file.
	image = cv2.imread(image_path)
	if(image is None):
		print ('cannot open image : %s' %(image_path))
		quit()

	# transite to gray scale
	image_gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)

	# get feature values.
	cascade = cv2.CascadeClassifier(cascade_path)

	# detect face.
	facerect = cascade.detectMultiScale(image_gray, scaleFactor=1.02, minNeighbors=3, minSize=(7,7))

	if len(facerect) > 0:

		saveDetectedFacesImg(image_path, facerect)
		trimmingFaces(image_path, facerect)

		print('can detect faces ! (^o^)')

	else:
		print('cannot detect faces...(>_<)')