OpenCV 4 with Python Blueprints - Second Edition

Handling video streams

The video stream of the webcam is handled by a series of steps that begin with the __init__ method. These steps might appear overly complicated at first, but they are necessary in order to allow the video to run smoothly, even at higher frame rates (that is, to counteract flickering).

The wxPython module works with events and callback methods. When a certain event is triggered, it can cause a certain class method to be executed (in other words, a method can bind to an event). We will use this mechanism to our advantage and display a new frame every so often using the following steps:

1. We create a timer that will generate a wx.EVT_TIMER event whenever 1000./self.fps milliseconds have passed:

 self.timer = wx.Timer(self) ...