由于海底管道背景复杂,简单的检测算法不能给出理想的检测结果;复杂的检测算法又不能满足实时作业要求。为了克服上述问题,实时而又准确地检测水下管道,通过分析水下图像的特点以及传统Hough变换对于管道直线信息提取的局限性,有针对性地提出了对Hough变换方法的2步改进,包括前期处理改善像素点的分布以减少参与Hough变换的无效像素点的数目,和Hough变换过程中的峰值点逆向清零以保证管道边界检测的唯一性。在仿真环境和水池环境下分别对改进的方法和未改进的方法进行了对比实验,结果表明前者可以有效地提高管道检测的实时性和精确性。
Simple detection methods couldn't carry out perfect pipeline extraction and complicated detection methods couldn't satisfy the real-time requirement since the sea background is really uncertain. Through analyzing the under-water image features and the limitation of pipeline extraction existing in traditional Hough transform, two steps of improvement are proposed to overcome such problems and carry out pipeline detection task as fast and correctly as possible. The new method includes improving pixel distribution to decrease the unnecessary pixels participating in sequent Hough transform and discarding the disturbance near the peak line conversely during Hough transform in order to guarantee the boundary uniqueness of the pipeline. Experiments in tank and simulation environment prove that the improved method is more accurate and less time-consuming compared with the un-improved method.