How to give Start, stop, capture and close buttons in Opencv Cam window in Python

Question

How to give start, stop, capture, and close buttons in video capture window to start, to stop, to take snapshot, to close the window?

I am using the below code to to open camera for video streaming:

import cv2.cv as cv
    cv.NamedWindow("camera", 1)
    capture = cv.CaptureFromCAM(0)
    while True:
        img = cv.QueryFrame(capture)
        cv.ShowImage("camera", img)
        if cv.WaitKey(10) == 27:
            break

btw, stick to the cv2 api, the old cv one won't be around for long — berak, Feb 03 '14 at 09:49
see https://www.pyimagesearch.com/2016/05/23/opencv-with-tkinter/ — Wolfgang Fahl, Nov 10 '19 at 16:55

score 3 · Accepted Answer · answered Feb 14 '17 at 13:01

Buttons aren't possible but you can use mouse clicks and key strokes to control your video. For example, use left click to toggle play/pause and implement record via key stroke:

import cv2

run=False
frame=0
path=#some video path

def foo(event, x, y, flags, param):
    global run
    global frame
    #check which mouse button was pressed
    #e.g. play video on left mouse click
    if event == cv2.EVENT_LBUTTONDOWN:
        run= not run
        while run:

            frame+=1
            frame=cap.read()[1]
            cv2.imshow(window_name, frame)
            key = cv2.waitKey(5) & 0xFF
            if key == ord("v"):
                pass
                #do some stuff on key press

    elif event == cv2.EVENT_RBUTTONDOWN:
        pass
        #do some other stuff on right click


window_name='videoPlayer'
cv2.namedWindow(window_name)
cv2.setMouseCallback(window_name, foo)

cap=cv2.VideoCapture(path)

SimonPJ · Answer 2 · 2014-02-03T11:07:30.610

0

I had this problem before with OpenCV. As far as I am aware there is no functionality for buttons in OpenCV.

However, I used Tkinter and created a canvas along with some buttons (in your case these will be start, stop, capture, close). Each frame that was captured using OpenCV I drew onto the Tkinter canvas.

I was using this for a frame by frame program, so I am not sure how well this method will perform in real time.

A very quick example code:

from Tkinter import *
import cv2.cv as cv

root = Tk()

w = Canvas(root, width=500, height=300, bd = 10, bg = 'white')
w.grid(row = 0, column = 0, columnspan = 2)

b = Button(width = 10, height = 2, text = 'Button1')
b.grid(row = 1, column = 0)
b2 = Button(width = 10, height = 2, text = 'Button2')
b2.grid(row = 1,column = 1)

cv.NamedWindow("camera",1)
capture = cv.CaptureFromCAM(0)

while True:
    img = cv.QueryFrame(capture)
    canvas.create_image(0,0, image=img)
    if cv.WaitKey(10) == 27:
        break

root.mainloop()

This may or may not work right off the bat as I am not in a position to test this right now. One potential change I can see would be the image format OpenCV uses. You may need to use one of the conversion functions to change the format.

edited Feb 03 '14 at 11:07

answered Feb 03 '14 at 09:28

SimonPJ

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9
21

hi SimonPJ, can you please share your sample code to create (start, stop, capture, close) buttons and functionality of it in python . – PSSR Feb 03 '14 at 09:33
If I can find the code I would be happy to share it. I did this a while back and was more of a play around, so I cant promise anything – SimonPJ Feb 03 '14 at 09:35
Hi SimonPJ can you please share sample code if you found it, i am not able to get any solution for this – PSSR Feb 03 '14 at 10:37
I am not at the computer it is saved on, but I can do some quick example code – SimonPJ Feb 03 '14 at 10:49
1

Hi it's not working for me please give me tested one if possible,Thanks – PSSR Feb 03 '14 at 13:34

How to give Start, stop, capture and close buttons in Opencv Cam window in Python

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