arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0909.3911cs.CV
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一种孤立车牌字符的提取与识别方法

A Method for Extraction and Recognition of Isolated License Plate Characters

National Chiao-Tung University(国立交通大学)

Yon Ping Chen, Tien Der Yeh

摘要:

提出了一种车牌中孤立字符的提取与识别方法。在提取阶段,该方法利用高斯差分(DOG)函数来检测孤立字符,与一系列其他可能的图像函数相比,DOG函数类似于高斯拉普拉斯函数,能够产生最稳定的图像特征。对不同尺度的DOG图像进行连通元分析,提取候选特征。在识别阶段,采用一种新的特征向量--累积梯度投影向量(AGPV)来比较候选字符和标准字符。通过首先将相似梯度方向的像素投影到特定轴上,然后按每个轴累积投影的梯度幅度来计算AGPV。实验证明,该方法具有图像缩放和旋转不变性,对噪声和光照变化具有鲁棒性。

英文摘要:

A method to extract and recognize isolated characters in license plates is proposed. In extraction stage, the proposed method detects isolated characters by using Difference-of-Gaussian (DOG) function, The DOG function, similar to Laplacian of Gaussian function, was proven to produce the most stable image features compared to a range of other possible image functions. The candidate characters are extracted by doing connected component analysis on different scale DOG images. In recognition stage, a novel feature vector named accumulated gradient projection vector (AGPV) is used to compare the candidate character with the standard ones. The AGPV is calculated by first projecting pixels of similar gradient orientations onto specific axes, and then accumulates the projected gradient magnitudes by each axis. In the experiments, the AGPVs are proven to be invariant from image scaling and rotation, and robust to noise and illumination change.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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