Presentation 2021-12-16
Neural Network-based Local Feature Descriptors for Matching Excavated Mokkan Fragments of Various Sizes
Trung Tan Ngo, Hung Tuan Nguyen, Masaki Nakagawa,
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Abstract(in Japanese) (See Japanese page)
Abstract(in English) This paper presents a method to predict whether two excavated Mokkan fragments of various sizes are from the same tablet or not using an end-to-end attention-based neural network, namely A-VLAD. The method does not require any preprocessing stages such as binarization and segmentation. It has three main parts: a local feature extractor using Convolutional Neural Network from an input image, an attention filter for key-points selection, and a generalized deep neural network-based VLAD model to aggregate the extracted key-points and form a representative vector. The whole network is trained end-to-end using the stochastic gradient descent algorithm to optimize both cross-entropy and triplet losses. In the experiments, we evaluate the proposed model on 13,205 fragments broken from 556 complete wooden tablets excavated from the Heijo-Kyo Palace ruins in the Japanese Nara period. The proposed A-VLAD model achieved mean average precision of 75.5% and top-1 accuracy of 87.9% better than the state-of-the-art methods on this Mokkan dataset. Thus, it is expected to be used to support archaeologists to assemble Mokkan fragments to recover an original Mokkan tablet.
Keyword(in Japanese) (See Japanese page)
Keyword(in English) MokkanHistorical documentsImage retrievalConvolution neural network
Paper # PRMU2021-33
Date of Issue 2021-12-09 (PRMU)

Conference Information
Committee PRMU
Conference Date 2021/12/16(2days)
Place (in Japanese) (See Japanese page)
Place (in English) Online
Topics (in Japanese) (See Japanese page)
Topics (in English)
Chair Seiichi Uchida(Kyushu Univ.)
Vice Chair Masakazu Iwamura(Osaka Pref. Univ.) / Mitsuru Anpai(Denso IT Lab.)
Secretary Masakazu Iwamura(NTT) / Mitsuru Anpai(Tottori Univ.)
Assistant Kouta Yamaguchi(CyberAgent) / Yusuke Matsui(Univ. of Tokyo)

Paper Information
Registration To Technical Committee on Pattern Recognition and Media Understanding
Language ENG
Title (in Japanese) (See Japanese page)
Sub Title (in Japanese) (See Japanese page)
Title (in English) Neural Network-based Local Feature Descriptors for Matching Excavated Mokkan Fragments of Various Sizes
Sub Title (in English)
Keyword(1) MokkanHistorical documentsImage retrievalConvolution neural network
1st Author's Name Trung Tan Ngo
1st Author's Affiliation Tokyo University of Agriculture and Technology(TUAT)
2nd Author's Name Hung Tuan Nguyen
2nd Author's Affiliation Tokyo University of Agriculture and Technology(TUAT)
3rd Author's Name Masaki Nakagawa
3rd Author's Affiliation Tokyo University of Agriculture and Technology(TUAT)
Date 2021-12-16
Paper # PRMU2021-33
Volume (vol) vol.121
Number (no) PRMU-304
Page pp.pp.51-56(PRMU),
#Pages 6
Date of Issue 2021-12-09 (PRMU)