The detection of small and medium-sized objects in three dimensions has always been a frontier exploration problem. This technology has a very wide application in sports analysis, games, virtual reality, human animation and other fields. The traditional three-dimensional small target detection technology has the disadvantages of high cost, low precision and inconvenience, so it is difficult to apply in practice. With the development of machine learning and deep learning, the technology of computer vision algorithms is becoming more mature. Creating an immersive media experience is considered to be a very important research work in sports. The main work is to explore and solve the problem of football detection under the multiple cameras, aiming at the research and implementation of the live broadcast system of football matches. Using multi cameras detects a target ball and determines its position in three dimension with the occlusion, motion, low illumination of the target object. This paper designed and implemented football detection system under multiple cameras for the detection and capture of targets in real-time matches. The main work mainly consists of three parts, football detector, single camera detection, and multi-cameras detection. The system used bundle adjustment to obtain the three-dimensional position of the target, and the GPU to accelerates data pre-processing and achieve accurate real-time capture of the target. By testing the system, it shows that the system can accurately detect and capture the moving targets in 3D. In addition, the solution in this paper is reusable for large-scale competitions, like basketball and soccer. The system framework can be well transplanted into other similar engineering project systems. It has been put into the market.

翻译：中小型目标的三维检测一直是前沿探索问题。该技术在运动分析、游戏、虚拟现实、人体动画等领域具有广泛应用。传统三维小目标检测技术存在成本高、精度低、不便携等缺点，难以在实际中应用。随着机器学习和深度学习的发展，计算机视觉算法技术日趋成熟。创建沉浸式媒体体验被认为是体育领域非常重要的一项研究工作。本文主要工作在于探索并解决多摄像头下的足球检测问题，旨在研究并实现足球比赛直播系统。通过使用多个摄像头检测目标球，并在存在遮挡、运动、低照度的情况下确定其三维位置。本文设计并实现了基于多摄像头的足球检测系统，用于实时比赛中的目标检测与捕捉。主要工作包括三个部分：足球检测器、单摄像头检测以及多摄像头检测。系统采用光束法平差获取目标的三维位置，并利用GPU加速数据预处理，实现目标的精确实时捕捉。经过系统测试，结果表明该系统能够精准检测并捕捉三维空间中的运动目标。此外，本文提出的解决方案可复用于篮球、足球等大规模比赛。该系统框架可良好移植至其他类似工程项目系统中，且已投入市场。