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[Author] Kazuaki NAKAMURA(4hit)

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  • Generation and Detection of Media Clones Open Access

    Isao ECHIZEN  Noboru BABAGUCHI  Junichi YAMAGISHI  Naoko NITTA  Yuta NAKASHIMA  Kazuaki NAKAMURA  Kazuhiro KONO  Fuming FANG  Seiko MYOJIN  Zhenzhong KUANG  Huy H. NGUYEN  Ngoc-Dung T. TIEU  

     
    INVITED PAPER

      Pubricized:
    2020/10/19
      Vol:
    E104-D No:1
      Page(s):
    12-23

    With the spread of high-performance sensors and social network services (SNS) and the remarkable advances in machine learning technologies, fake media such as fake videos, spoofed voices, and fake reviews that are generated using high-quality learning data and are very close to the real thing are causing serious social problems. We launched a research project, the Media Clone (MC) project, to protect receivers of replicas of real media called media clones (MCs) skillfully fabricated by means of media processing technologies. Our aim is to achieve a communication system that can defend against MC attacks and help ensure safe and reliable communication. This paper describes the results of research in two of the five themes in the MC project: 1) verification of the capability of generating various types of media clones such as audio, visual, and text derived from fake information and 2) realization of a protection shield for media clones' attacks by recognizing them.

  • Discrimination between Genuine and Cloned Gait Silhouette Videos via Autoencoder-Based Training Data Generation

    Yuki HIROSE  Kazuaki NAKAMURA  Naoko NITTA  Noboru BABAGUCHI  

     
    PAPER-Pattern Recognition

      Pubricized:
    2019/09/06
      Vol:
    E102-D No:12
      Page(s):
    2535-2546

    Spoofing attacks are one of the biggest concerns for most biometric recognition systems. This will be also the case with silhouette-based gait recognition in the near future. So far, gait recognition has been fortunately out of the scope of spoofing attacks. However, it is becoming a real threat with the rapid growth and spread of deep neural network-based multimedia generation techniques, which will allow attackers to generate a fake video of gait silhouettes resembling a target person's walking motion. We refer to such computer-generated fake silhouettes as gait silhouette clones (GSCs). To deal with the future threat caused by GSCs, in this paper, we propose a supervised method for discriminating GSCs from genuine gait silhouettes (GGSs) that are observed from actual walking people. For training a good discriminator, it is important to collect training datasets of both GGSs and GSCs which do not differ from each other in any aspect other than genuineness. To this end, we propose to generate a training set of GSCs from GGSs by transforming them using multiple autoencoders. The generated GSCs are used together with their original GGSs for training the discriminator. In our experiments, the proposed method achieved the recognition accuracy of up to 94% for several test datasets, which demonstrates the effectiveness and the generality of the proposed method.

  • Development and Evaluation of Near Real-Time Automated System for Measuring Consumption of Seasonings

    Kazuaki NAKAMURA  Takuya FUNATOMI  Atsushi HASHIMOTO  Mayumi UEDA  Michihiko MINOH  

     
    PAPER-Human-computer Interaction

      Pubricized:
    2015/09/07
      Vol:
    E98-D No:12
      Page(s):
    2229-2241

    The amount of seasonings used during food preparation is quite important information for modern people to enable them to cook delicious dishes as well as to take care for their health. In this paper, we propose a near real-time automated system for measuring and recording the amount of seasonings used during food preparation. Our proposed system is equipped with two devices: electronic scales and a camera. Seasoning bottles are basically placed on the electronic scales in the proposed system, and the scales continually measure the total weight of the bottles placed on them. When a chef uses a certain seasoning, he/she first picks up the bottle containing it from the scales, then adds the seasoning to a dish, and then returns the bottle to the scales. In this process, the chef's picking and returning actions are monitored by the camera. The consumed amount of each seasoning is calculated as the difference in weight between before and after it is used. We evaluated the performance of the proposed system with experiments in 301 trials in actual food preparation performed by seven participants. The results revealed that our system successfully measured the consumption of seasonings in 60.1% of all the trials.

  • Preventing Fake Information Generation Against Media Clone Attacks Open Access

    Noboru BABAGUCHI  Isao ECHIZEN  Junichi YAMAGISHI  Naoko NITTA  Yuta NAKASHIMA  Kazuaki NAKAMURA  Kazuhiro KONO  Fuming FANG  Seiko MYOJIN  Zhenzhong KUANG  Huy H. NGUYEN  Ngoc-Dung T. TIEU  

     
    INVITED PAPER

      Pubricized:
    2020/10/19
      Vol:
    E104-D No:1
      Page(s):
    2-11

    Fake media has been spreading due to remarkable advances in media processing and machine leaning technologies, causing serious problems in society. We are conducting a research project called Media Clone aimed at developing methods for protecting people from fake but skillfully fabricated replicas of real media called media clones. Such media can be created from fake information about a specific person. Our goal is to develop a trusted communication system that can defend against attacks of media clones. This paper describes some research results of the Media Clone project, in particular, various methods for protecting personal information against generating fake information. We focus on 1) fake information generation in the physical world, 2) anonymization and abstraction in the cyber world, and 3) modeling of media clone attacks.