Medium:Imagetopdf Load images and convert to gray scale

imagetopdf_rgbtogray.py

files_in_dir=os.listdir()
curr_path=os.getcwd()

#get image file names in current directory
image_names=[]
conventions=['jpeg','png','jpg']
for file in files_in_dir:
	ext=file.split('.')[-1]
	if ext in conventions:
		image_names.insert(0,file)

#Read images into opencv numpy arrays
images_read=[]
for name in image_names:
	img=cv2.imread(name)
	images_read.insert(0,img)

#Convert RGB images to Gray Scale
thsh_images=[]
for img in images_read:
	img_gray=cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)
	clahe=cv2.createCLAHE(clipLimit=4.0,tileGridSize=(16,16))
	img_gray=clahe.apply(img_gray)
	ret,th=cv2.threshold(img_gray,130,255,cv2.THRESH_BINARY)
	thsh_images.append(th)