使用特徵影像的移動物追蹤

Development of feature-based visual tracking for moving objects

李威漢(Wei-hen Lee)

指導教授 ： 陳傳生

元智大學/工程學院/機械工程學系/碩士(2006年)

https://doi.org/10.6838/YZU.2006.00224

摘要

視覺追蹤是根據一具以上的攝影機隨著畫面所出現的目標物移動，計算適當的攝影機轉動/移動位移，使目標物能保持在畫面內的伺服控制方法。視覺追蹤可以應用在保全監視、機械臂裝配工作、無人駕駛車輛、飛機的導航與目標追蹤。

在固定式攝影機的環境下，追蹤影像中的移動物體是很簡單的，因為在攝影機的連績畫面中背景是不會變化的，所以當影像中有運動物體時，只要將相鄰的兩張影像相減，計算出其中的灰階值差異處，即可辨認出影像中該物體的位置。而移動式攝影機的視覺追蹤就比較複雜，因為背景會變化的關係，上述的方法並不適用，所以如何在這種環境下，找出真正運動的物體（對地面而言），是件非常困難且重要的工作。

在本論文中，提供了一種移動式攝影機追蹤影像中運動物體的方法。利用feature tracking做為研究的基礎，找出影像中多個特徵處，以特徵處的移動做為分類條件，並對其所有的移動做高斯機率分佈，分離背景和移動物體，最後納入權重值的方法，強建移動物體，濾除光流量的計算錯誤，達到追蹤移動物體的目的。

關鍵字

機械視覺,影像追蹤

並列摘要

Visual tracking means a camera can track a moving target while the spatial relationship between the camera and the target is changing. Visual tracking has found many applications in security surveillance, robot assembly, autonomous vehicles navigations and moving objects tracking.

It is easy to track moving objects in a fixed camera because of the static background. But it is a challenging and hard task for tracking moving objects in a moving camera. In this paper, we describe how image sequence taken by a moving camera may be processed to detect and track moving objects against a moving background in real-time. Motion is found by tracking image features, segmentation is based on feature’s velocity, and to filter background features using Gaussian normal distribution. Finally, we use weighting approach for filtering the error of optical flow computation and enhancing moving objects tracking.

並列關鍵字

Computer Vision, Image Tracking, Feature-Based, Motion Segmentation

參考文獻

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