How to make buttons in OpenCV 3.1 using cv2.createButton?

Question

I'm trying to add a button to my image processing script to save the high and low HSV values for my binary threshold.

According to the OpenCV 3.0 documentation here, OpenCV evidently has a function which does that.

I am writing the function like this
cv2.createButton('Button',f)
Where Button is the name of the button and f is the callback function (just an empty function)

However I keep on getting:-

AttributeError: 'module' object has no attribute 'createButton'

Apparently the same function works fine with C/C++ but it isn't working with python. Most probably because it isn't there for python (maybe) ?

How do I get around this problem?

Solution 1

The documentation says

Another important application of trackbar is to use it as a button or switch. OpenCV, by default, doesn’t have button functionality. So you can use trackbar to get such functionality (found at Trackbar as the Color Palette).

There is a small example how to use it as button.

Solution 2

cv2.namedWindow("Frame")
cv2.createButton("Back",back,None,cv2.QT_PUSH_BUTTON,1)

def back(*args):
    pass

The above code shows how to implement the cv2.createButton() method.

Notes:

• "Back" = text displayed on the button
• back = function called when the button is pressed
• the cv2 window must be created before the button
• if your button is not appearing: click inside the frame, press ctrl+p or command+p (for mac) and the button menu should appear

Comments

[ppasler]

@DuncanWhyte indeed, but as I see it, it is the closest thing to OP's question.

[edison]

It works to create a button in a pop-up named "Python settings" that is launched from an invisible button set (10) on top of the frame.

[edison]

BTW I'm using opencv-python v4.4.0

[Ramtin Nouri]

It is possible. You have to compile OpenCV yourself and make sure to enable QT support

[mins]

So what is the reason AttributeError: 'module' object has no attribute 'createButton' does appear? cv2 has indeed a function createButton, even if as of today the documentation doesn't show the correct parameter names.

[ArduinoBen]

hmm why do we need ctrl+p>