Implement KNN Background Subtraction

[Blindspot22]

Description:

• Implement the KNN (K-Nearest Neighbors) algorithm as an alternative method for background subtraction.

Implementation Steps:

• Import the BackgroundSubtractorKNN module from OpenCV.
• Initialize the KNN background subtractor using BackgroundSubtractorKNN::default.
• Modify the video processing loop to apply the KNN background subtractor to each frame, similar to the MOG2 implementation.
• Retrieve and display the foreground mask generated by the KNN algorithm, comparing it with the MOG2 output.
• Experiment with and adjust KNN-specific parameters such as the history, distance threshold, and detect shadows to optimize performance.