东南大学学报(英文版)
東南大學學報(英文版)
동남대학학보(영문판)
JOURNAL OF SOUTHEAST UNIVERSITY
2014年
1期
27-31
,共5页
黄鹤鸣%达飞鹏%韩晓旭
黃鶴鳴%達飛鵬%韓曉旭
황학명%체비붕%한효욱
模式识别%小波变换%梯度方向%藏文%手写字符
模式識彆%小波變換%梯度方嚮%藏文%手寫字符
모식식별%소파변환%제도방향%장문%수사자부
pattern recognition%wavelet transform%gradient direction%Tibetan%handwritten character
为了提高脱机手写藏文字符的识别效果,提出了一种在小波变换基础上计算局部梯度方向直方图的特征提取方法。首先,对一个脱机手写藏文字符样本图像进行一次 Haar 小波变换,得到相应的一级近似分量;然后,将这个一级近似分量划分成几个等尺寸的子区域;最后,计算每个等尺寸子区域的局部梯度方向直方图,并将所有子区域的全部局部梯度方向直方图的值作为该字符图片的特征。在最近建立的脱机手写藏文字符样本数据库(THCDB)上的实验结果表明:提出的特征提取方法识别效率较高,且识别效果较好;和细节分量相比,近似分量对提高识别精度具有更大的贡献。
為瞭提高脫機手寫藏文字符的識彆效果,提齣瞭一種在小波變換基礎上計算跼部梯度方嚮直方圖的特徵提取方法。首先,對一箇脫機手寫藏文字符樣本圖像進行一次 Haar 小波變換,得到相應的一級近似分量;然後,將這箇一級近似分量劃分成幾箇等呎吋的子區域;最後,計算每箇等呎吋子區域的跼部梯度方嚮直方圖,併將所有子區域的全部跼部梯度方嚮直方圖的值作為該字符圖片的特徵。在最近建立的脫機手寫藏文字符樣本數據庫(THCDB)上的實驗結果錶明:提齣的特徵提取方法識彆效率較高,且識彆效果較好;和細節分量相比,近似分量對提高識彆精度具有更大的貢獻。
위료제고탈궤수사장문자부적식별효과,제출료일충재소파변환기출상계산국부제도방향직방도적특정제취방법。수선,대일개탈궤수사장문자부양본도상진행일차 Haar 소파변환,득도상응적일급근사분량;연후,장저개일급근사분량화분성궤개등척촌적자구역;최후,계산매개등척촌자구역적국부제도방향직방도,병장소유자구역적전부국부제도방향직방도적치작위해자부도편적특정。재최근건립적탈궤수사장문자부양본수거고(THCDB)상적실험결과표명:제출적특정제취방법식별효솔교고,차식별효과교호;화세절분량상비,근사분량대제고식별정도구유경대적공헌。
To improve the recognition accuracy of off-line handwritten Tibetan characters the local gradient direction histograms based on the wavelet transform are proposed as the recognition features.First for a Tibetan character sample image the first level approximation component of the Haar wavelet transform is calculated.Secondly the approximation component is partitioned into several equal-sized zones. Finally the gradient direction histograms of each zone are calculated and the local direction histograms of the approximation component are considered as the features of the character sample image.The proposed method is tested on the recently developed off-line Tibetan handwritten character sample database.The experimental results demonstrate the effectiveness and efficiency of the proposed feature extraction method.Furthermore compared with the detail components the approximation component contributes more to the recognition accuracy.