NOISE REMOVAL DEVICE AND NOISE REMOVAL METHOD

• Main Author: KANEKO MASAYOSHI
• Format: Patent
• Language: English; Japanese
• Published: 09.05.2016
• Subjects: ACOUSTICS; MUSICAL INSTRUMENTS; PHYSICS; SPEECH ANALYSIS OR SYNTHESIS; SPEECH OR AUDIO CODING OR DECODING; SPEECH OR VOICE PROCESSING; SPEECH RECOGNITION

PROBLEM TO BE SOLVED: To improve the accuracy of removal when removing noise in a waveform using a probability model.SOLUTION: Adopted as a probability model in a noise removal device which, when estimating the waveform at each time of day in accordance with a probability model using time-series data comprising data representing the waveform at each time of day, removes a waveform component whose occurrence probability is low in the estimation from the time-series data as noise, is a model that includes a visible element corresponding to the waveform at each time of day and a hidden element that makes a pair with the visible element, and also includes recurrence elements in forward and reverse directions that realize a transition between visible elements that are in a row in the time-series direction, a transition between hidden elements that are in a row in the time-series direction, or a transition between visible and hidden elements at adjacent times of day. The data at each time of day is correlated to the visible elements at each time of day, and the waveform at each time of day is estimated from the past visible and hidden elements earlier than the time of day and the future visible and hidden elements ahead of the time of day in accordance with the transition indicated by the recurrence element.SELECTED DRAWING: Figure 1 【課題】確率モデルを用いて波形の雑音除去を行う際の除去精度を向上させる。【解決手段】各時刻の波形を表すデータよりなる時系列データを用いて確率モデルにしたがって各時刻の波形を推定した場合に生起確率が低い波形成分を雑音として前記時系列データから除去する雑音除去装置における確率モデルとして、各時刻の波形に対応する可視素子と当該可視素子と対になる隠れ素子とを含むとともに、時間軸方向に並んだ可視素子間の遷移、時間軸方向に並んだ隠れ素子間の遷移、または隣接する時刻における可視素子と隠れ素子との間の遷移を実現する順方向および逆方向の再帰素子を含むモデルを採用する。そして、各時刻のデータを各時刻の可視素子に対応付け、各時刻の波形を再帰素子の示す遷移にしたがって当該時刻よりも過去の可視素子および隠れ素子と当該時刻よりも未来の可視素子および隠れ素子とから推定する。【選択図】 図１