Show webcam sequence TkInter

Question

I did a program with python, importing the OpenCV's libraries. Now, I'm doing the GUI in Tkinter. I'm trying to show the webcam in the GUI but I couldn't. I put the code in the Function because I would like with a push button see my webcam.

My code is:

def webcam():
   img= cv.QueryFrame(cap)
   cam= PhotoImage(img)
   label1 = Label(root, image=cam)
   label1.image = cam
   label1.pack()
   label1.place(x=0, y=400)

Also, I don't know how update constantly without a while cycle, because I have another push button to quit the program.

Answer 1

A simple version of camera capture using OpenCv and Tkinter:

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

width, height = 800, 600
cap = cv2.VideoCapture(0)
cap.set(cv2.CAP_PROP_FRAME_WIDTH, width)
cap.set(cv2.CAP_PROP_FRAME_HEIGHT, height)

root = tk.Tk()
root.bind('<Escape>', lambda e: root.quit())
lmain = tk.Label(root)
lmain.pack()

def show_frame():
    _, frame = cap.read()
    frame = cv2.flip(frame, 1)
    cv2image = cv2.cvtColor(frame, cv2.COLOR_BGR2RGBA)
    img = Image.fromarray(cv2image)
    imgtk = ImageTk.PhotoImage(image=img)
    lmain.imgtk = imgtk
    lmain.configure(image=imgtk)
    lmain.after(10, show_frame)

show_frame()
root.mainloop()

You will need to download and install PIL...

UPDATE:

... and OpenCV for this to work.

To Install PIL, run the following command in your Terminal/Command Prompt:

pip install Pillow or python -m pip install Pillow

To Install OpenCV, run the following command in your Terminal/Command Prompt:

pip install opencv-python or python -m pip install opencv-python

Answer 2

Kieleth's updated code for py3.7

import PIL
from PIL import Image,ImageTk
import pytesseract
import cv2
from tkinter import *
width, height = 800, 600
cap = cv2.VideoCapture(0)
cap.set(cv2.CAP_PROP_FRAME_WIDTH, width)
cap.set(cv2.CAP_PROP_FRAME_HEIGHT, height)

root = Tk()
root.bind('<Escape>', lambda e: root.quit())
lmain = Label(root)
lmain.pack()

def show_frame():
    _, frame = cap.read()
    frame = cv2.flip(frame, 1)
    cv2image = cv2.cvtColor(frame, cv2.COLOR_BGR2RGBA)
    img = PIL.Image.fromarray(cv2image)
    imgtk = ImageTk.PhotoImage(image=img)
    lmain.imgtk = imgtk
    lmain.configure(image=imgtk)
    lmain.after(10, show_frame)

show_frame()
root.mainloop()

Answer 3

Try this code:

from collections import deque
import cv2
from PIL import Image, ImageTk
import time
import Tkinter as tk

def quit_(root):
    root.destroy()

def update_image(image_label, cam):
    (readsuccessful, f) = cam.read()
    gray_im = cv2.cvtColor(f, cv2.COLOR_BGR2GRAY)
    a = Image.fromarray(gray_im)
    b = ImageTk.PhotoImage(image=a)
    image_label.configure(image=b)
    image_label._image_cache = b  # avoid garbage collection
    root.update()


def update_fps(fps_label):
    frame_times = fps_label._frame_times
    frame_times.rotate()
    frame_times[0] = time.time()
    sum_of_deltas = frame_times[0] - frame_times[-1]
    count_of_deltas = len(frame_times) - 1
    try:
        fps = int(float(count_of_deltas) / sum_of_deltas)
    except ZeroDivisionError:
        fps = 0
    fps_label.configure(text='FPS: {}'.format(fps))


def update_all(root, image_label, cam, fps_label):
    update_image(image_label, cam)
    update_fps(fps_label)
    root.after(20, func=lambda: update_all(root, image_label, cam, fps_label))


if __name__ == '__main__':
    root = tk.Tk() 
    image_label = tk.Label(master=root)# label for the video frame
    image_label.pack()
    cam = cv2.VideoCapture(1) 
    fps_label = tk.Label(master=root)# label for fps
    fps_label._frame_times = deque([0]*5)  # arbitrary 5 frame average FPS
    fps_label.pack()
    # quit button
    quit_button = tk.Button(master=root, text='Quit',command=lambda: quit_(root))
    quit_button.pack()
    # setup the update callback
    root.after(0, func=lambda: update_all(root, image_label, cam, fps_label))
    root.mainloop()

Answer 4

I have done it and working successfully. Here is the Link

I havent assigned button to show the frame but you can assign a button and run to get your answer. I know the use of global variable is a bad practice but still i am using it. Hope it helps.

Answer 5

The solution proposed by Kieleth worked well for me in a Jupyter notebook. However, I would suggest you destroy root and release cap after the mainloop. Without doing that, the kernel will have to be reset every time.