Overview

I wrote a python script that crops the specified coordinates from many images.

background

When I screen the web conference screen, I do a full screen screenshot so as not to be late for the discussion, but when I share it with people later, I want to erase unnecessary information on the screen such as the toolbar, so I made it. If it's about a few, you can do it with a Mac preview, but it's often on the order of about 100, so I thought it would be convenient if you could do it all at once with a program.

environment

macOS Catalina 10.15.7 python 3.8.0

Installation

pip install Pillow

This time I will use Pillow. You can also do it with OpenCV.

code

# -*- coding: utf-8 -*-
import sys
from PIL import Image
import os

#Image storage location before cropping
ORIGINAL_FILE_DIR = "./org_data/"
#Storage destination of cropped image
TRIMMED_FILE_DIR = "./cut_data/"

#Returns a cropped image object, specifying the image path, upper left and lower right coordinates.
def trim(path, left, top, right, bottom):
  im = Image.open(path)
  im_trimmed = im.crop((left,top,right,bottom))
  return im_trimmed
  
  
if __name__ == '__main__':
  #If there is no storage destination for the cropped image, create it
  if os.isdir(TRIMMED_FILE_DIR) == False:
    os.makedirs(TRIMMED_FILE_DIR)
    
  #Upper left coordinates to trim
  left, top = 0, 50
  #Top right coordinates to trim
  right, bottom = 2880, 1800
   
  #Get image file name
  files = os.listdir(ORIGINAL_FILE_DIR)
  #Only files with a specific extension are used. Match the extension of the file to be actually processed
  files = [name for name in files if name.split(".")[-1] in ["png","jpg"]]
  
  for val in files:
    #Path to the original image
    path = ORIGINAL_FILE_DIR + val
    #Get a cropped image object
    im_trimmed = trim(path, left, top, right, bottom)
    #Save to the trimmed directory. At the beginning of the file name"cut_"Is on
    im_trimmed.save(TRIMMED_FILE_DIR+"cut_"+val, quality=95) #quality is not recommended if it is greater than 95

When actually using it, prepare the storage destination of the image before and after trimming, and specify the directory with a relative path in the source code. Then run the program.

in conclusion

It is troublesome to select the area each time when taking a screenshot, so I think that there is a considerable demand for full-screen screenshots and cutting later. I screened the web conferencing screen, trimmed it this way, and then pasted it into PowerPoint with python. I hope it helps you.