近年來，自動駕駛汽車為全球發展的重要目標，不論白天或晚上自動駕駛系統都需要準確地偵測行人與車輛。這意味著我們不能依靠普通的RGB相機來偵測周圍環境，因為它對於光線敏感度很高，在晚上或是下雨天時拍出來的影像會不清晰，所以我們選擇使用光學雷達（LiDAR），該感測器可以生成三維點雲，其中每個點表示與物體的距離。在本論文中，我們提出了一種方法，僅使用由LiDAR生成的三維點雲來檢測行人與車輛。我們方法首先是項目將三維點雲包刮點雲資訊映射到二維平面。然後我們提取三維點雲和映射後的二維圖片特徵和來自卷積神經網絡的特徵以訓練支持向量機（SVM）來偵測行人與車輛。我們提出的方法在F1-度量法比現有技術方法取得了顯著的改進。

In recent years, self-driving cars are an important goal for global development. Autopilot systems need to be able to detect pedestrians or vehicles with high precision and recall regardless of whether it is during the day or night. This means that we cannot rely on normal cameras to sense the surroundings due to its sensitivity to lighting conditions. An alternative for images is to use light detection and ranging sensors (LiDAR) that produce three-dimensional point clouds where each point represents the distance to an object. However, most pedestrian or vehicle detection systems are designed for image inputs and not on distance point clouds. In his paper, we propose a method for detecting pedestrians and vehicles using only the three-dimensional point clouds generated by the LiDAR. Our approach first projects the three-dimensional point cloud include point cloud information into a two-dimensional plane. We then extract both hand-crafted features and learned features from a convolutional neural network in order to train a support vector machine (SVM) to detect pedestrians and vehicles. Our proposed method achieved significant improvements in terms of F1-measurement over prior state-of-the-art methods.

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