利用調整光流法進行障礙物偵測基於逆透視轉換運用於行車安全

An Improved Obstacle Detection Using Optical Flow Adjusting Based on Inverse Perspective Mapping for the Vehicle Safety

洪肇澤(Chao-Tse Hong)

指導教授 ： 駱榮欽

國立臺北科技大學/電資學院/電腦與通訊研究所/碩士(2012年)

https://doi.org/10.6841/NTUT.2012.00219

摘要

本論文中，我們實現了一個基於逆透視轉換的光流法來檢測車輛周圍的障礙物。然而，類似的方法已被提出並且在車輛上使用。但這種方法只限於車輛是直線行駛時。如果車輛在轉彎的情況下，會使車輛左右兩側影像的光流值有所不一致，這將導致障礙物誤辨識。因此我們提出了一個方法來改善這個問題，這個方法是利用車輛的移動軌跡來計算轉彎的中心點。再利用轉彎的中心點來修正光流值的不一致。經過改善方法後可以讓光流值保持一致性，即使車輛在轉彎中。並且利用CUDA加速，使此系統可即時運行。

關鍵字

攝影機校正 ； 逆透視轉換 ； 鳥瞰圖 ； 光流法 ； 障礙物偵測 ； 影像處理

並列摘要

In this paper, we implement and improve a method to detect obstacles around the vehicle by optical flow computation based on inverse perspective mapping. However, similar methods had been proposed and used on the vehicle. But this approach is limited on a trajectory of the vehicle which moves along with a straight line. If the trajectory of the vehicle moves along with an arc line, the optical flow values will inconsistent in the left side and in the right side of this image which causes mistakes in obstacle detection. So we propose a method to improve this problem which uses the trajectory of vehicle to calculate the center of turning circle. And the center of turning circle can be used to adjust the inconsistent with optical flow values. After our improvement, the optical flow values can keep the consistence even if the trajectory is along with an arc line. Besides, we implement this system with CUDA in real-time.

並列關鍵字

Camera Calibration ； Inverse Perspective Mapping ； Optical Flow ； Obstacle Detection ； Image Processing

參考文獻

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