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[Author] Motoi IWATA(12hit)

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  • Information Hiding and Its Criteria for Evaluation Open Access

    Keiichi IWAMURA  Masaki KAWAMURA  Minoru KURIBAYASHI  Motoi IWATA  Hyunho KANG  Seiichi GOHSHI  Akira NISHIMURA  

     
    INVITED PAPER

      Pubricized:
    2016/10/07
      Vol:
    E100-D No:1
      Page(s):
    2-12

    Within information hiding technology, digital watermarking is one of the most important technologies for copyright protection of digital content. Many digital watermarking schemes have been proposed in academia. However, these schemes are not used, because they are not practical; one reason for this is that the evaluation criteria are loosely defined. To make the evaluation more concrete and improve the practicality of digital watermarking, watermarking schemes must use common evaluation criteria. To realize such criteria, we organized the Information Hiding and its Criteria for Evaluation (IHC) Committee to create useful, globally accepted evaluation criteria for information hiding technology. The IHC Committee improves their evaluation criteria every year, and holds a competition for digital watermarking based on state-of-the-art evaluation criteria. In this paper, we describe the activities of the IHC Committee and its evaluation criteria for digital watermarking of still images, videos, and audio.

  • Correlation-Based Video Watermarking Method Using Inter-Frame Similarity

    Motoo YAMAMOTO  Akira SHIOZAKI  Motoi IWATA  Akio OGIHARA  

     
    PAPER-Information Hiding

      Vol:
    E89-A No:1
      Page(s):
    186-193

    This paper presents a correlation-based watermarking method for video using the similarity of adjacent frames. In general, the adjacent frames of a video sequence is very similar. In the proposed scheme, we use an adjoining frame in detection process instead of an original image in the watermarking scheme of Cox et al. So the proposed method does not need an original video sequence in detection process. When a watermarked video sequence is attacked by overwriting copy or frame dropping, the pair of the frames that is not adjoining in an original video sequence is used in detection process. However, since a watermark is embedded in a part of each frame and embedding positions are different for each frame in the proposed method, we can detect the watermark even from an overwriting-copied video sequence and a frame-dropped video sequence. Experimental results show that the proposed method is robust against overwriting copy and frame dropping. Moreover, it is shown from experimental results that the method has robustness to low bitrate MPEG compression and StirMark attack.

  • Watermarking Method for Embedding Index Data into Images Utilizing Features of Wavelet Transform

    Motoi IWATA  Akira SHIOZAKI  

     
    PAPER-Image

      Vol:
    E84-A No:7
      Page(s):
    1772-1778

    It is necessary for anyone to be able to extract embedded index data without specific keys or secret information when index data are embedded into digital contents. In this paper, we propose a new data hiding technique for embedding index data into color images using wavelet transform. In our method, we prevent image quality from degrading by utilizing not specific keys but features of wavelet transform. The method extracts index data without specific keys and is tolerant of edge-enhancement, gamma correction, brightness conversion and lossy image compression such as JPEG compression.

  • Digital Watermarking Method to Embed Index Data into JPEG Images

    Motoi IWATA  Kyosuke MIYAKE  Akira SHIOZAKI  

     
    LETTER-Information Security

      Vol:
    E85-A No:10
      Page(s):
    2267-2271

    This letter proposes a method which can embed index data such as memos into JPEG images. The method embeds digital watermarks using the quantitative relation between quantized DCT coefficients in JPEG images. In the method, we can embed extra data to represent index data and can extract the index data without parameters used in embedding process. Furthermore, the method is tolerant of JPEG recompression and prevents the degradation of image quality by rewriting index data.

  • Index Data Embedding Method Utilizing Quantitative Relation of Wavelet Coefficients

    Motoi IWATA  Akira SHIOZAKI  

     
    PAPER-Information Security

      Vol:
    E84-A No:10
      Page(s):
    2508-2513

    It is necessary condition for digital watermarking method for embedding memos or index data into digital photograph and so on that anyone can extract embedded data without specific keys or secret information. In this paper, we propose a data hiding technique for embedding index data into color images using wavelet transform. The proposed method keeps image quality and robustness against JPEG compression and general image processing using quantitative relation of wavelet coefficients.

  • Face Image Generation of Anime Characters Using an Advanced First Order Motion Model with Facial Landmarks

    Junki OSHIBA  Motoi IWATA  Koichi KISE  

     
    PAPER

      Pubricized:
    2022/10/12
      Vol:
    E106-D No:1
      Page(s):
    22-30

    Recently, deep learning for image generation with a guide for the generation has been progressing. Many methods have been proposed to generate the animation of facial expression change from a single face image by transferring some facial expression information to the face image. In particular, the method of using facial landmarks as facial expression information can generate a variety of facial expressions. However, most methods do not focus on anime characters but humans. Moreover, we attempted to apply several existing methods to anime characters by training the methods on an anime character face dataset; however, they generated images with noise, even in regions where there was no change. The first order motion model (FOMM) is an image generation method that takes two images as input and transfers one facial expression or pose to the other. By explicitly calculating the difference between the two images based on optical flow, FOMM can generate images with low noise in the unchanged regions. In the following, we focus on the aspect of the face image generation in FOMM. When we think about the employment of facial landmarks as targets, the performance of FOMM is not enough because FOMM cannot use a facial landmark as a facial expression target because the appearances of a face image and a facial landmark are quite different. Therefore, we propose an advanced FOMM method to use facial landmarks as a facial expression target. In the proposed method, we change the input data and data flow to use facial landmarks. Additionally, to generate face images with expressions that follow the target landmarks more closely, we introduce the landmark estimation loss, which is computed by comparing the landmark detected from the generated image with the target landmark. Our experiments on an anime character face image dataset demonstrated that our method is effective for landmark-guided face image generation for anime characters. Furthermore, our method outperformed other methods quantitatively and generated face images with less noise.

  • Reversible Watermarking Method for JPEG Images

    Akira SHIOZAKI  Motoi IWATA  Akio OGIHARA  

     
    LETTER-Application Information Security

      Vol:
    E91-D No:7
      Page(s):
    2068-2071

    In this letter, we propose a simple reversible watermarking method for JPEG images using the characteristics of JPEG compression. The method embeds a watermark into a JPEG image, and it extracts the watermark from the watermarked JPEG image and at the same time can recover the watermarked JPEG image to an original unwatermarked JPEG image. Moreover we investigate the number of embeddable blocks, the quality of watermarked images, and the increase of file-size by embedding a watermark.

  • Exploring Sensor Modalities to Capture User Behaviors for Reading Detection

    Md. Rabiul ISLAM  Andrew W. VARGO  Motoi IWATA  Masakazu IWAMURA  Koichi KISE  

     
    LETTER-Human-computer Interaction

      Pubricized:
    2022/06/20
      Vol:
    E105-D No:9
      Page(s):
    1629-1633

    Accurately describing user behaviors with appropriate sensors is always important when developing computing cost-effective systems. This paper employs datasets recorded for fine-grained reading detection using the J!NS MEME, an eye-wear device with electrooculography (EOG), accelerometer, and gyroscope sensors. We generate models for all possible combinations of the three sensors and employ self-supervised learning and supervised learning in order to gain an understanding of optimal sensor settings. The results show that only the EOG sensor performs roughly as well as the best performing combination of other sensors. This gives an insight into selecting the appropriate sensors for fine-grained reading detection, enabling cost-effective computation.

  • Digital Watermarking Method for Printed Matters Using Deep Learning for Detecting Watermarked Areas

    Hiroyuki IMAGAWA  Motoi IWATA  Koichi KISE  

     
    PAPER

      Pubricized:
    2020/10/07
      Vol:
    E104-D No:1
      Page(s):
    34-42

    There are some technologies like QR codes to obtain digital information from printed matters. Digital watermarking is one of such techniques. Compared with other techniques, digital watermarking is suitable for adding information to images without spoiling their design. For such purposes, digital watermarking methods for printed matters using detection markers or image registration techniques for detecting watermarked areas are proposed. However, the detection markers themselves can damage the appearance such that the advantages of digital watermarking, which do not lose design, are not fully utilized. On the other hand, methods using image registration techniques are not able to work for non-registered images. In this paper, we propose a novel digital watermarking method using deep learning for the detection of watermarked areas instead of using detection markers or image registration. The proposed method introduces a semantic segmentation based on deep learning model for detecting watermarked areas from printed matters. We prepare two datasets for training the deep learning model. One is constituted of geometrically transformed non-watermarked and watermarked images. The number of images in this dataset is relatively large because the images can be generated based on image processing. This dataset is used for pre-training. The other is obtained from actually taken photographs including non-watermarked or watermarked printed matters. The number of this dataset is relatively small because taking the photographs requires a lot of effort and time. However, the existence of pre-training allows a fewer training images. This dataset is used for fine-tuning to improve robustness for print-cam attacks. In the experiments, we investigated the performance of our method by implementing it on smartphones. The experimental results show that our method can carry 96 bits of information with watermarked printed matters.

  • Practical Watermarking Method Estimating Watermarked Region from Recaptured Videos on Smartphone

    Motoi IWATA  Naoyoshi MIZUSHIMA  Koichi KISE  

     
    PAPER

      Pubricized:
    2016/10/07
      Vol:
    E100-D No:1
      Page(s):
    24-32

    In these days, we can see digital signages in many places, for example, inside stations or trains with the distribution of attractive promotional video clips. Users can easily get additional information related to such video clips via mobile devices such as smartphone by using some websites for retrieval. However, such retrieval is time-consuming and sometimes leads users to incorrect information. Therefore, it is desirable that the additional information can be directly obtained from the video clips. We implement a suitable digital watermarking method on smartphone to extract watermarks from video clips on signages in real-time. The experimental results show that the proposed method correctly extracts watermarks in a second on smartphone.

  • Digital Steganography Utilizing Features of JPEG Images

    Motoi IWATA  Kyosuke MIYAKE  Akira SHIOZAKI  

     
    PAPER-Image

      Vol:
    E87-A No:4
      Page(s):
    929-936

    This paper proposes a new steganographic method utilizing features of JPEG compression. The method embeds secret information using the number of zeroes in a block of quantized DCT coefficients in minimum coding units (MCU) of JPEG images. In the method, we can embed secret information into JPEG images with degradation like that by JPEG compression. Furthermore, the method causes little change of the histogram of quantized DCT coefficients, so it is hard to perceive secret information embedded by the method. The method mainly modifies boundaries between zero and non-zero DCT coefficients, so we can use the low frequency side of DCT coefficients for another steganographic method.

  • A Digital Image Watermarking Scheme Withstanding Malicious Attacks

    Akira SHIOZAKI  Jiro TANIMOTO  Motoi IWATA  

     
    PAPER-Information Security

      Vol:
    E83-A No:10
      Page(s):
    2015-2022

    In this paper, we propose a new watermarking method which spreads an ID pattern with specific sequences and embeds it throughout the spatial domain of an image. A set of the sequences is a key for extracting the ID pattern. As an ID pattern is spread throughout an image, we can extract the ID pattern from a part of the image, that is a clipped image. We can also confirm authenticity by extracting the same ID pattern from several parts of an image. The proposed method is robust to StirMark, which is a benchmark tool to test robustness of watermarked images, as well as disturbance by noise addition and common image processing operations such as edge-enhancement, brightness-contrast conversion, posterization, Gauss filtering, median filtering, gamma correction, JPEG compression and clipping.