如何在 Tkinter 界面中显示来自 OpenCV 的图像？

Question

我正在尝试在取自 OpenCV 的 VideoCapture 的 Tkinter 界面中连续显示和替换图像。 但是，我收到以下错误，我认为这是图像 numpy 数组格式不正确的结果：

类型错误：不可散列类型：'numpy.ndarray'

如何将其重新格式化为所有内容以正确显示？ 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PIL.Image.fromarray()支持的格式。

其次最好不要在主线程中使用 while 循环，因为它会阻塞 tkinter 主循环。 使用after()代替。

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()