Embedment with Area Ratio for Camera - Based Character
نویسندگان
چکیده
あらまし ディジタルカメラを入力デバイスとして実環境中の文字を高精度に認識するために,文字画像と同 時に認識補助のための付加情報を提示する方法が検討されている.付加情報は,人間にとって自然な形で提示さ れること,及び,幾何学的変形に対してロバストに抽出できることが要求される.本論文では,これらの要求を 満たす手法として,面積比を利用した付加情報提示手法を提案する.すなわち,文字パターンを 2 色で印字する ことを前提とし,それぞれの色の領域の面積比を特定の値とするようにデザインする.具体的には,文字に影を 付加したり輪郭線を別の色とする.これらは文字パターンのデザインとして既に行われており,提案手法はその 線幅や面積を変えるにすぎない.したがって,提案手法は様々な用途に広く応用することが可能である.面積比 はアフィン変換に不変であり,アフィン変換を受けた環境においても誤りなく抽出されることが期待される.実 際に付加情報を埋め込んだ文字パターンを作成し,ディジタルカメラで撮影された画像中の文字パターンから付 加情報を抽出する実験を行い,提案手法の有効性を確認する.また,付加情報を用いて文字を認識する実験を行 い,認識精度が向上することを確認する. キーワード 実環境文字認識,情報埋込,付加情報,アフィン不変量,面積比
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†Graduate School of Engineering, Tohoku University Aoba 6-6-05, Aramaki, Aoba-ku, Sendai-shi, 980-8579 Japan E-mail: [email protected] ††Graduate School of Engineering, Osaka Prefecture University 1-1 Gakuen-cho, Naka-ku, Sakai-shi, Osaka, 599-8531 Japan E-mail: {masa, kise}@cs.osakafu-u.ac.jp †††Faculty of Information Science and Electrical Engineering, Kyushu University 744 Motooka, Nis...
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