auto_crop.py

import os
import cv2
import sys
import dlib
from imutils import face_utils

def crop_boundary(top, bottom, left, right, faces):
    if faces:
        top = max(0, top - 200)
        left = max(0, left - 100)
        right += 100
        bottom += 100
    else:
        top = max(0, top - 50)
        left = max(0, left - 50)
        right += 50
        bottom += 50

    return (top, bottom, left, right)

def crop_face(imgpath, dirName, extName):
    frame = cv2.imread(imgpath)
    basename = os.path.basename(imgpath)
    basename_without_ext = os.path.splitext(basename)[0]
    if frame is None:
        return print(f"Invalid file path: [{imgpath}]")
    frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
    face_detect = dlib.get_frontal_face_detector()
    rects = face_detect(gray, 1)
    if not len(rects):
        return print(f"Sorry. HOG could not detect any faces from your image.\n[{imgpath}]")
    for (i, rect) in enumerate(rects):
        (x, y, w, h) = face_utils.rect_to_bb(rect)
        
        top, bottom, left, right = crop_boundary(y, y + h, x, x + w, len(rects) <= 2)
        crop_img_path = os.path.join(dirName, f"{basename_without_ext}_crop_{i}{extName}")
        crop_img = frame[top: bottom, left: right]
        cv2.imwrite(crop_img_path, cv2.cvtColor(crop_img, cv2.COLOR_RGB2BGR))

    return print(f"SUCCESS: [{basename}]")
        
def main(argv):
    extName = ".png"
    dirName = "result"
    os.makedirs(dirName, exist_ok=True)

    if len(argv) == 1:
        sys.exit("Usage: python crop_face.py <image path> ...")
    
    for i in range(1, 81): 
        imgpath = "2/img"+str(i)+".jpg"
        print(imgpath)
        crop_face(imgpath, dirName, extName)


        
if __name__ == "__main__":
    main(sys.argv)