Calibration of and stereo measurements from two synchronized event cameras

This repository contains files related to the <i>left</i> camera (Gen4.1 sensor in the Prophesee's Evaluation Kit 2) and <i>right</i> camera (IMX636 ES sensor in Prophesee's Evaluation Kit 4) of a stereo setup of two event cameras. The event cameras were synchronized electronically such that time stamps in both event streams were produced by synchronized clocks. The raw files can be viewed and analyzed using Prophesee's Metavision Studio or any of the other tools provided in the Metavision SDK. A projector produces two different levels of illumination with a sharp transition making up a scanning contrast edge. This contrast edge moves through the measurement volume in order to sample the surfaces of the scene and sequentially trigger corresponding events in both event cameras.Calibration dataCalibration data of the stereo setup of event cameras is contained in the files <i>left_recorded_patterns.json</i> and <i>right_recorded_patterns.json</i>, which were recorded based on the metavision mono calibration recording tool. These files contain a common description of the employed checkerboard pattern in the form of 3D points of the corners (JSON field "pattern_3d") which are all assumed to lie in the same plane. The grid distances along the edges of the pattern ("square_width" and "square_height") provide scaling to the calibration. Lists of 2D positions of identified corners are found in the field "pts_2d". Each list corresponds to the checkerboard pattern as observed by the stereo setup from a different pose. The order of poses is the same in both calibration files.Stereo measurementsRaw event streams of both event cameras of different scenes sampled by a projector are saved in the <i>contrast_series</i> and <i>object_series </i>subdirectories. For each measurement there is a '...<i>left.csv' and a '...</i>right.csv' file which are the temporally synchronized event streams of a single measurement. Furthermore, there is a '...<i>params.json'</i> file for each measurement. They contain the upper and lower levels of illuminance that the projector produces, measured at the center of the measurement volume. Additionaly, they contain the bias parameters for the cameras used in each measurement. There is also a ground truth point cloud of the stairs object<i> ('</i><i>object</i><i>series/stairs_ground_truth.asc</i>') reconstructed from measurements of a different 3D sensor. The contrast series contains measurements of a plane object measured with different contrasts of the scanning contrast edge. There are five repetitions for each contrast. The object series contains single measurements of multiple objects.本仓库包含与双目事件相机系统的左相机（Prophesee评估套件2搭载Gen4.1传感器）和右相机（Prophesee评估套件4搭载IMX636 ES传感器）相关的文件。两台事件相机通过电子方式实现同步，两路事件流的时间戳均由同步时钟生成。 原始文件可通过Prophesee的Metavision Studio或Metavision SDK提供的其他工具进行查看与分析。 一台投影仪可产生两种不同照度等级、带有锐利过渡边界的扫描对比度边缘。该对比度边缘在测量视场内移动，以对场景表面进行采样，并依次触发两台事件相机中的对应事件。 校准数据 双目事件相机系统的校准数据存储于`left_recorded_patterns.json`与`right_recorded_patterns.json`文件中，二者通过Metavision单目校准录制工具生成。文件中以棋盘格（Checkerboard）角点的三维坐标（JSON字段"pattern_3d"）形式包含了所用棋盘格图案的通用描述，所有角点均假定位于同一平面。图案边缘的网格间距（"square_width"与"square_height"）为校准提供缩放基准。已识别角点的二维位置列表存储于字段"pts_2d"中，每个列表对应双目系统从不同位姿观测到的棋盘格图案。两份校准文件中的位姿顺序完全一致。 立体测量 经投影仪采样的不同场景的两路事件相机原始事件流，分别存储于`contrast_series`与`object_series`子目录中。每次测量对应一对`*_left.csv`与`*_right.csv`文件，二者为单次测量的时序同步事件流。此外，每次测量还配有一个`*_params.json`文件，其中包含投影仪在测量视场中心产生的照度上下限。该文件还包含每次测量所用相机的偏置参数。本数据集还包含从另一台三维传感器的测量结果重建得到的楼梯对象真值点云文件（`object_series/stairs_ground_truth.asc`）。 对比度序列目录存储了使用不同扫描对比度边缘照度的平面对象测量数据，每种对比度均进行五次重复测量。对象序列目录则包含了多种对象的单次测量数据。