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研究生: 卓訓發
Cho, Hsun-Fa
論文名稱: 以長短期記憶模型進行筆寫單字辨識
On-Pen Handwritten Word Recognition Using Long Short-Term Memory Model
指導教授: 周百祥
Chou, Pai H.
口試委員: 蔡明哲
Tsai, Ming-Jer
周志遠
Chou, Jerry
學位類別: 碩士
Master
系所名稱:
論文出版年: 2018
畢業學年度: 106
語文別: 英文
論文頁數: 32
中文關鍵詞: 嵌入式系統筆寫辨識手勢辨識深度學習連續資料分段長短期記憶模型
外文關鍵詞: embedded system, op-pen handwritten recognition, gesture recognition, deep learning, segmentation of continuous data, long short-term memory model
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  • 近年來,因穿戴式裝置的流行,基於動作感測的手寫辨識研究越來越多,例如空中手寫、智慧筆等等,但是能達到實用水平的應用卻很少。受限於感測器的限制、連續動作的分割難度這些問題,手寫動作辨識很難做有效率的文字輸入。在這篇論文中,我們提出了一種安裝在筆上的新型硬體裝置,搭配以長短期記憶模型(LSTM)為核心的辨識系統,讓使用者能夠用任何他們想拿來寫字的筆,作為一個有效率的文字輸入介面。


    This thesis describes a system for text input from handwriting using a
    conventional pen with a clip-on sensing unit. The clip-on unit is a
    wireless sensor node that collects data from a triaxial accelerometer and a triaxial gyroscope and transmits it to a conventional personal computer. The host computer then performs segmentation to handle continuous handwriting, followed by LSTM-based classification. Moreover, we use a lexicon-based corrector to increase the accuracy. Experimental results show our proposed system to achieve good accuracy and reasonable latency for interactive use.

    Contents i Acknowledgments iv 1 Introduction 1 1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Contributions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.3 Thesis Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2 Related Work 3 2.1 Isolated Handwriting Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.2 Continuous Handwriting Recognition . . . . . . . . . . . . . . . . . . . . . . . . . 4 3 System Overview 6 3.1 Pen Subsystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.2 Host Subsystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4 Data Preprocessing and Segmentation 8 4.1 Gravity Elimination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.2 Signal Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 4.3 Data segmentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4.3.1 Related Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4.3.2 Our Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5 Recognition Method 15 5.1 Background: RNN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 5.2 Long Short-Term Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 i 5.3 Lexicon Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 5.3.1 Bayes’ Corrector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 5.3.2 Weighted Levenshtein distance . . . . . . . . . . . . . . . . . . . . . . . . . 19 6 Evaluation 21 6.1 Experimental Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 6.1.1 Data Acquisition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 6.1.2 System environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 6.2 Experimental Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 6.2.1 Segmentation Robustness . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 6.2.2 Accuarcy of Using Different Features . . . . . . . . . . . . . . . . . . . . . 24 6.2.3 Improvement After Lexicon Support . . . . . . . . . . . . . . . . . . . . . . 24 6.3 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 7 Conclusions and Future Work 28 7.1 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 7.2 Future Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

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