Institute of Photogrammetry & Remote Sensing, TU Dresden, 01069 Dresden, Germany.
Sensors (Basel). 2020 Jan 23;20(3):643. doi: 10.3390/s20030643.
Knowledge about the interior and exterior camera orientation parameters is required to establish the relationship between 2D image content and 3D object data. Camera calibration is used to determine the interior orientation parameters, which are valid as long as the camera remains stable. However, information about the temporal stability of low-cost cameras due to the physical impact of temperature changes, such as those in smartphones, is still missing. This study investigates on the one hand the influence of heat dissipating smartphone components at the geometric integrity of implemented cameras and on the other hand the impact of ambient temperature changes at the geometry of uncoupled low-cost cameras considering a Raspberry Pi camera module that is exposed to controlled thermal radiation changes. If these impacts are neglected, transferring image measurements into object space will lead to wrong measurements due to high correlations between temperature and camera's geometric stability. Monte-Carlo simulation is used to simulate temperature-related variations of the interior orientation parameters to assess the extent of potential errors in the 3D data ranging from a few millimetres up to five centimetres on a target in X- and Y- direction. The target is positioned at a distance of 10 m to the camera and the Z-axis is aligned with camera's depth direction.
需要了解内部和外部摄像机方向参数，以建立 2D 图像内容与 3D 对象数据之间的关系。摄像机校准用于确定内部方位参数，只要摄像机保持稳定，这些参数就是有效的。然而，由于智能手机等设备的温度变化等物理影响，有关低成本摄像机的时间稳定性的信息仍然缺失。本研究一方面调查了散热智能手机组件对摄像机几何完整性的影响，另一方面调查了环境温度变化对未耦合低成本摄像机的几何形状的影响，考虑了暴露于受控热辐射变化的 Raspberry Pi 相机模块。如果忽略这些影响，将图像测量值转换为物体空间将导致错误的测量，因为温度与相机几何稳定性之间存在高度相关性。蒙特卡罗模拟用于模拟与温度相关的内部方位参数变化，以评估在 X 和 Y 方向上从几毫米到五厘米的目标上的 3D 数据中的潜在误差程度。目标距离相机 10 米，Z 轴与相机的深度方向对齐。
