[Tkinter] Load image and show in label

[deanhystad]

A program that reads and writes image files using opencv and displays them in tkinter.

import tkinter as tk
from tkinter import filedialog
from PIL import Image, ImageTk
import cv2

class Application(tk.Tk):
    def __init__(self, image_path=None):
        super().__init__()
        self.title("Image Processing")
        self.geometry("400x300")
    
        self.image = None   # Image used for image processing
        self.tkimage = None # Image used to display in tkinter label
    
        self.display = tk.Label(self)
        self.display.pack(expand=True, fill=tk.BOTH)

        # Make a frame to pack the buttons horizontally
        buttons = tk.Frame(self)
        buttons.pack(side=tk.BOTTOM, fill=tk.X, padx=5, pady=5)

        # Make buttons to load image, save image and quit
        button = tk.Button(buttons, text="LOAD IMAGE", command=self.load_image)
        button.pack(side=tk.LEFT, expand=True, fill=tk.X)
        button = tk.Button(buttons, text="SAVE FILE", command=self.save_image)
        button.pack(side=tk.LEFT, expand=True, fill=tk.X, padx=5)
        button = tk.Button(buttons, text="CLOSE", command=self.destroy)
        button.pack(side=tk.LEFT, expand=True, fill=tk.X)

    def load_image(self):
        """Select an image to display"""
        filename = filedialog.askopenfilename()
        if filename:
            # Read image and convert to RGB
            self.image = cv2.imread(filename)
            self.image = cv2.cvtColor(self.image, cv2.COLOR_BGR2RGB)

            # Convert image to tkinter image format and display
            self.tkimage = ImageTk.PhotoImage(Image.fromarray(self.image))
            self.display["image"] = self.tkimage

    def save_image(self):
        """Save image to a file"""
        filename = filedialog.asksaveasfilename(defaultextension='.jpg')
        if filename:
            # Convert image to BGR and write to file.
            cv2.imwrite(filename, cv2.cvtColor(self.image, cv2.COLOR_RGB2BGR))

Application().mainloop()