以立體視覺實作盲人輔具系統

A Stereo-Vision-Based Aid System for the Blind

謝易錚(Yi-Zeng Hsieh)

指導教授 ： 蘇木春

國立中央大學/資訊電機學院/資訊工程學系/碩士(2006年)

摘要

視障人士位於不熟悉的環境中，想要了解整各環境的概況，必須使用白手杖（White Cane），去觸碰地面或是物體以確認前方是否可以行走以及障礙物的位置，而手杖不能碰觸的地方則無從得知。使用者只有在面臨障礙物時才被輔具所引導閃避，並沒有自主選擇行走路徑的能力，因此希望開發出一套系統，能夠將環境中的資訊，先告知視障人士，並配合白手杖的使用，根據系統的提示，自己選擇需要移動的方向，增加盲人行走的安全與自主性。
本論文中提出以立體視覺的方式，先切割出環境的路面區域，利用影像量化，非路面區域根據量化的影像區塊去做影像比對，利用分群的方法去除影像雜訊，建立出陌生環境資訊，偵測出障礙物體，並指出障礙物離盲人多遠與障礙物方向，當盲人在行走時，可以先預知行走環境的整體資訊，利用此資訊並搭配白手杖的使用，達到盲人行走安全，以達到解決使用者-「障礙物位於哪裡？ 離障礙物體有多遠？障礙物大小？」的疑惑。藉由此初步的研究，即能令目前導盲的輔具化被動為主動，讓視障人士的行動更為自由。

關鍵字

立體視覺 ； 行動輔具

並列摘要

White Cane is the most pervasive travel-aid for the blind. We present an idea of using stereo matching to develop a travel aid for the blind. In this approach, first we use a segmentation algorithm to segment the floor region from the image captured by the web camera. Then images are segmented into several non-overlapping homogeneous regions using a color segmentation algorithm. For each homogeneous region, a rectangular window, which is large enough to cover the region, is found. A local match with the found rectangular window size is then executed to find the disparity for the considered region. A clustering algorithm is adopted to cluster the disparities into several major different values. Finally, a piece-wise disparity map is constructed. Based on the disparity map, information about the unfamiliar environments in front of the blind will be output to them. With the information about the environment the blind will have less fear in walking through unfamiliar environments via white canes.

並列關鍵字

stereo matching ； travel aid

參考文獻

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