光フロー

光フロー

光フロー is a concept in コンピュータビジョン and 画像処理 that refers to the pattern of motion of objects as perceived through a sequence of images. It is derived from the movement of objects between two or more frames captured by a camera. By analyzing these changes, algorithms can estimate the velocity of objects, their direction, and even depth perception.

光フローは、物体の見かけの動きが観測者（カメラ）の動きとシーン内の物体の動きの両方の結果であるという原理に基づいています。この動きは通常、ベクトル場として表され、各ベクトルは1つのフレームから次のフレームへの物体ピクセルの動きを示します。

光フローの計算には、2つの主なアプローチがあります： 密な光フロー and 疎な光フロー. Dense optical flow calculates motion vectors for every pixel in the image, providing a comprehensive view of all object movements. In contrast, sparse optical flow focuses on specific feature points, tracking their motion across frames. Both methods have their unique applications and advantages.

Optical flow is widely used in various applications including video surveillance, autonomous driving, motion analysis, and 拡張現実. It helps systems understand dynamic environments by interpreting how objects move relative to each other and the observer. Furthermore, it plays a crucial role in the development of algorithms for object tracking, scene reconstruction, and motion-based segmentation.