videoDisplayWorker.py
The purpose of the videoDisplay module is to simply use OpenCV methods to open a new window and display a user’s webcam to that window. This module also uses the decklinksrc module to retrieve and display frames.
Video display in python uses OpenCV, which is a library of programming functions that allow various functionalities in real-time computer vision. This includes video and image processing, object detection, tracking, and many more. In the videoDisplayWorker.py file, the OpenCV library is imported and used to display the user’s default webcam.
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As mentioned before, main.py runs decklinkSrcWorker_taxi() and videoDisplay() functions at the same time. The frame acquired by decklinkSrcWorker_taxi() is instantly passed into videoDisplay() and output to the screen. This is done continuously to create a full video stream. The high-speed frames that are acquired and output is what creates a functional webcam display. 
The flowchart below demonstrates the path of the showVideo() function in main.py.
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