python - 如何在Tkinter界面中显示来自OpenCV的图像？

Question

我正在尝试从OpenCV的VideoCapture获取的Tkinter界面中连续显示和替换图像。但是，我收到以下错误，我认为是图像nu​​mpy数组格式不正确的结果:

TypeError: unhashable type: 'numpy.ndarray'

如何将其重新格式化为可以正常显示的所有内容？下面是我的代码:

import tkinter as tk
import cv2
import numpy as np
from PIL import ImageTk, Image

main = tk.Tk()
main.title("Hole Pattern Recognition")
main.geometry("300x300")

frame = tk.Frame(main)
frame.pack()

def startScan():
    global main, frame
    #begins utilizing webcam for scan
    cap = cv2.VideoCapture(0)
    while(True):
        ret,img = cap.read()
        img = ImageTk.PhotoImage(img)
        panel = tk.Label(main, image = img)
        panel.pack(side = "bottom", fill = "both", expand = "yes")
        ch = cv2.waitKey(1)
        if ch == ord('q'):
            break
        
    cap.release()
    cv2.destroyAllWindows()

    
    
startButton = tk.Button(frame, 
                   text="Start Scan", 
                   fg="blue",
                   command=startScan)

startButton.pack(side=tk.TOP)
main.mainloop()

Answer 1

首先，您需要使用PIL.Image.fromarray()将捕获的图像转换为tkinter支持的格式。
其次最好不要在主线程中使用while循环，因为它将阻塞tkinter mainloop。请改用after()。

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

cap = None

main = tk.Tk()
main.title('Hole Pattern Recognition')
#main.geometry('300x300')

frame = tk.Frame(main)
frame.pack()

def startScan():
    global cap

    def scan():
        ret, img = cap.read()
        if ret:
            img = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
            img = Image.fromarray(img)
            tkimg = ImageTk.PhotoImage(img)
            panel.config(image=tkimg)
            panel.tkimg = tkimg # save a reference to the image to avoid garbage collection
        panel.after(25, scan) # change 25 to other value to adjust FPS

    if cap is None:
        cap = cv2.VideoCapture(0)
        scan() # start the capture loop
    else:
        print('capture already started')

startButton = tk.Button(frame, text='Start Scan', fg='blue', command=startScan)
startButton.pack()

panel = tk.Label(main)
panel.pack()

main.mainloop()

if cap:
    cap.release()