應用頻譜分析與支援向量機於車牌定位之研究

A Study on License Plate Localization with Spectrum Analysis and Support Vector Machines.

劉瀚升(Han-Sheng Liu)

指導教授 ： 林穎宏

共同指導教授 ： 黃詰琳(Chieh-Ling Huang)

長榮大學/資訊暨工程學院/資訊管理研究所/碩士(2009年)

https://doi.org/10.6833/CJCU.2009.00035

摘要

車牌辨識系統中的車牌定位至關重要，在車輛圖像中往往存在許多類似車牌的區域，準確地定位出車牌所在的區域，才能正確的攫取出所需的資訊，以利後續車牌辨識。本研究提出一車牌定位方法，首先對拍攝之影像進行頻譜分析以取得特徵，再使用小波轉換與支援向量機定位正確的車輛牌照位置，所提出之方法經300組實測例子驗證，其定位準確率達96.6%，所提出方法整合至車牌辨識系統中可提高車牌辨識的正確率。

關鍵字

車牌辨識 ； 車牌定位 ； 頻譜分析 ； 小波轉換 ； 支援向量機

並列摘要

Vehicle license plate localization plays an important role in vehicle license plate recognition system. Actually, there are many possible areas similar to license plate within an image. In order to facilitate the accuracy of vehicle license plate recognition, it is important to localize accurately the area of vehicle license plate for obtaining useful information from an image. In this study, a two-step approach for vehicle license plate localization is proposed. The first step is to perform spectrum analysis on the image for extracting features. Then, wavelet transform and support vector machines is used to localize the area of vehicle license plate. The proposed method have been evaluated through 300 test cases, and the correctness of license plate localization is 96.6 %. Thus, integrating the proposed method into license plate recognition system will advance its correctness.

並列關鍵字

Vehicle license plate recognition ； Vehicle license plate localization ； Spectrum analysis ； Wavelet transform ； Support Vector Machines

參考文獻

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