Masakazu Iwamura

Dr. Masakazu Iwamura

orcid

Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 August 2015
Verified
Conference Paper
Closed access
DKDimosthenis Karatzas
Dimosthenis Karatzas
LGLluis Gomez
Lluis Gomez
ANAnguelos Nicolaou
Anguelos Nicolaou
SGSuman Ghosh
Suman Ghosh
ABAndrew Bagdanov
Andrew Bagdanov
EVErnest Valveny
Ernest Valveny
Results of the ICDAR 2015 Robust Reading Competition are presented. A new Challenge 4 on Incidental Scene Text has been added to the Challenges on Born-Digital Images, Focused Scene Images and Video Text. Challenge 4 is run on a newly acquired dataset of 1,670 images evaluating Text Localisation, Word Recognition and End-to-End pipelines. In addition, the dataset for Challenge 3 on Video Text has been substantially updated with more video sequences and more accurate ground truth data. Finally, tasks assessing End-to-End system performance have been introduced to all Challenges. The competition took place in the first quarter of 2015, and received a total of 44 submissions. Only the tasks newly introduced in 2015 are reported on. The datasets, the ground truth specification and the evaluation protocols are presented together with the results and a brief summary of the participating methods.

1 August 2013
Verified
Conference Paper
Closed access
DKDimosthenis Karatzas
Dimosthenis Karatzas
FSFaisal Shafait
Faisal Shafait
SUSeiichi Uchida
Seiichi Uchida
MIMasakazu Iwamura
Masakazu Iwamura
LGLluis Gomez
Lluis Gomez
LHLluis Pere de Las Heras
Lluis Pere de Las Heras
This report presents the final results of the ICDAR 2013 Robust Reading Competition. The competition is structured in three Challenges addressing text extraction in different application domains, namely born-digital images, real scene images and real-scene videos. The Challenges are organised around specific tasks covering text localisation, text segmentation and word recognition. The competition took place in the first quarter of 2013, and received a total of 42 submissions over the different tasks offered. This report describes the datasets and ground truth specification, details the performance evaluation protocols used and presents the final results along with a brief summary of the participating methods.

18 December 2019 in IEEE Access
Verified
Journal Article
Open access
YYYoshihiro Yamada
Yoshihiro Yamada
MIMasakazu Iwamura
Masakazu Iwamura
TATakuya Akiba
Takuya Akiba
Koichi KiseKoichi Kise
Koichi Kise
Overfitting is a crucial problem in deep neural networks, even in the latest network architectures. In this paper, to relieve the overfitting effect of ResNet and its improvements (i.e., Wide ResNet, PyramidNet, and ResNeXt), we propose a new regularization method called ShakeDrop regularization. ShakeDrop is inspired by Shake-Shake, which is an effective regularization method, but can be applied to ResNeXt only. ShakeDrop is more effective than Shake-Shake and can be applied not only to ResNeXt but also ResNet, Wide ResNet, and PyramidNet. An important key is to achieve stability of training. Because effective regularization often causes unstable training, we introduce a training stabilizer, which is an unusual use of an existing regularizer. Through experiments under various conditions, we demonstrate the conditions under which ShakeDrop works well.

1 January 2006
Verified
Book Chapter
Closed access
PDF file
TNTomohiro Nakai
Tomohiro Nakai
KKKoichi Kise
Koichi Kise
MIMasakazu Iwamura
Masakazu Iwamura

12 April 2021 in Applied Sciences
Verified
Journal Article
Open access
PDF file
Debashis Das ChakladarDebashis Das Chakladar
Debashis Das Chakladar
PKPradeep Kumar
Pradeep Kumar
SMShubham Mandal
Shubham Mandal
PRPartha Roy
Partha Roy
MIMasakazu Iwamura
Masakazu Iwamura
Byung-Gyu  KimByung-Gyu Kim
Byung-Gyu Kim
Sign language is a visual language for communication used by hearing-impaired people with the help of hand and finger movements. Indian Sign Language (ISL) is a well-developed and standard way of communication for hearing-impaired people living in India. However, other people who use spoken language always face difficulty while communicating with a hearing-impaired person due to lack of sign language knowledge. In this study, we have developed a 3D avatar-based sign language learning system that converts the input speech/text into corresponding sign movements for ISL. The system consists of three modules. Initially, the input speech is converted into an English sentence. Then, that English sentence is converted into the corresponding ISL sentence using the Natural Language Processing (NLP) technique. Finally, the motion of the 3D avatar is defined based on the ISL sentence. The translation module achieves a 10.50 SER (Sign Error Rate) score.

1 September 2011
Verified
Conference Paper
Closed access
KTKazutaka Takeda
Kazutaka Takeda
KKKoichi Kise
Koichi Kise
MIMasakazu Iwamura
Masakazu Iwamura
This paper presents a real-time document image retrieval method for a large-scale database with Locally Likely Arrangement Hashing (LLAH). In general, when a database is scaled up, a large amount of memory is required and retrieval accuracy drops due to insufficient discrimination power of features. To solve these problems, we propose three improvements: memory reduction by sampling feature points, improvement of discrimination power by increasing the number of feature dimensions and stabilizing features by reducing redundancy. From the experimental results, we have confirmed that the proposed method realizes 50% memory reduction, and achieves 99.4% accuracy and 38ms processing time for a database of 10 million pages.