CV2

CV2 refers to the Python bindings for the OpenCV library, a widely used open-source toolkit for computer vision and image processing. The module name cv2 is what Python code imports when using OpenCV, for example with import cv2. OpenCV itself is a cross-platform library that provides a C++ core with language bindings, and cv2 exposes many of its capabilities to Python.

CV2 covers a broad range of tasks, including image input and output, color space conversions, geometric transformations, filtering and image enhancement, edge and corner detection, contour analysis, feature detection and matching, object detection with classifiers or deep learning models, camera calibration, and basic 3D reconstruction. It also provides access to machine learning utilities and a variety of algorithms implemented in OpenCV. The library is designed to work with NumPy arrays, so images and video frames are manipulated as multi-dimensional arrays.

Typical workflows in cv2 include reading an image with cv2.imread, converting color spaces with cv2.cvtColor, applying filters such as cv2.GaussianBlur, detecting edges with cv2.Canny, and saving results with cv2.imwrite. For video, it can capture frames from cameras or video files and process them in real time.

Implementation and installation details: cv2 is a Python interface to the OpenCV C++ core, and most users access it via prebuilt binaries. It is commonly installed through pip with packages such as opencv-python or opencv-python-headless; for access to extra contributed modules, opencv-contrib-python is used. OpenCV is distributed under a permissive BSD license, and cv2 is the primary means by which Python developers leverage OpenCV’s capabilities.