A study on sound source segregation of frequency domain binaural model with reflection

반사음이 존재하는 양귀 모델의 음원분리에 관한 연구

  • Received : 2014.06.17
  • Accepted : 2014.08.02
  • Published : 2014.07.30

Abstract

For Sound source direction and separation method, Frequency Domain Binaural Model(FDBM) shows low computational cost and high performance for sound source separation. This method performs sound source orientation and separation by obtaining the Interaural Phase Difference(IPD) and Interaural Level Difference(ILD) in frequency domain. But the problem of reflection occurs in practical environment. To reduce this reflection, a method to simulate the sound localization of a direct sound, to detect the initial arriving sound, to check the direction of the sound, and to separate the sound is presented. Simulation results show that the direction is estimated to lie close within 10% from the sound source and, in the presence of the reflection, the level of the separation of the sound source is improved by higher Coherence and PESQ(Perceptual Evaluation of Speech Quality) and by lower directional damping than those of the existing FDBM. In case of no reflection, the degree of separation was low.

두 개의 입력소자에 의한 음원방향 및 분리방법으로서는 연산량이 적고, 음원분리 성능이 높은 주파수 양귀 모델(Frequency Domain Binaural Model : FDBM)이 있다. FDBM은 주파수 영역에서 양귀간 위상차(Interaural Phase Difference : IPD) 및 양귀간 레벨차(Interaural Level Difference : ILD)를 구하여 음향신호가 오는 방향과 음원의 분리처리를 한다. 그러나 실제 환경에서는 반사음의 문제가 되고 있다. 이러한 반사음에 의한 영향을 줄이기 위하여 선행음 효과에 의한 직접음의 음상정위를 모의하여 초기 도착음을 검출하고 직접음이 오는 방향과 음원분리 방법을 제시하였다. 제시한 방법을 이용하여 음원방향 추정 및 분리에 대한 성능을 시뮬레이션으로 검토하였다. 그 결과, 방향추정은 음원이 오는 방향에서 ${\pm}10%$의 범위로 집중되어 음원의 방향과 가까운 값으로 추정되었다, 반사음이 존재하는 경우의 음원분리는 기존의 FDBM에 비하여 코히런스(Coherence), 음성품질 지각평가 PESQ(Perceptual Evaluation of Speech Quality : PESQ)가 높고, 정면에서의 지향특성 감쇠량이 작아 분리의 정도가 개선됨을 나타내었다. 그러나 반사음이 존재하지 않는 경우는 분리 정도가 낮았다.

Keywords

References

  1. Markus Bodden, "Modeling human sound-source localization and the cocktail-party-effect," Acta Acoustica, 1, pp. 43-55, 1993.
  2. W. Lindemann, "Extension of a binaural cross-correlation model by contralateral inhibitation. I. Simulation of lateralization for stationary signals," J. Acoust. Soc. Am., 80(6), pp. 1608-1622, 1986. https://doi.org/10.1121/1.394325
  3. W. Lindemann, "Extension of a binaural cross-correlation model by contralateral inhibitation. II. The low of the first wave front," J. Acoust. Soc. Am., 80(6), pp. 1623-1630, 1986. https://doi.org/10.1121/1.394326
  4. Shoji Makino, Hirosh Sawada, Ryo Mukai and Sho Araki, "Blind Source Separation of Convolutive Mixtures of Speech in Frequency Domain," IEICE Trans. Fundamentals, E88-A, pp. 1640-1655, 2005. https://doi.org/10.1093/ietfec/e88-a.7.1640
  5. C.H. Knapp and G.C. Carter, "The generalized correlation method for estimation of time delay," IEEE Trans. Acoust. Speech Signal Process," ASSP-24, pp. 320-327, 1976.
  6. H. Nakashima, N. Sato, T. Nakanishi, T. Usagawa and M. Ebata, "Speech Signal Enhancement Based on the Frequency Domain Binaural Model," Proc. Internoise 2003, N562, pp. 1486-1492, 2003.
  7. H. Nakashima, T. Usagawa, "Frequency domain binaural model based on interaural phase and levrl difference," Acoustical Science & Technology Vol. 24, No. 4, pp. 172-178, 2003.
  8. Y. Chisaki, S. Kawano, K. Nagata, K.Mastuo,"Azimuthal and elevation location of two sound sources using interaural phase and level difference," Acoustical Science & Technology, Vol. 29, No. 2, pp. 139-148, 2008. https://doi.org/10.1250/ast.29.139
  9. 이채봉, "FDBM의 음원분리 성능평가," 한국전자통신학회, Vol. 8, No. 12, pp. 1793-1801, 2013.
  10. 채종덕, 이채봉, "반사음이 음상정위에 미치는 영향," 2013하계학술대회 논문집, 한국신호처리시스템학회, pp. 8-10, 2013.
  11. Suzuki, Kaneta, "The estimated method of sound source direction with sub-band peak hold process," JASA, Vol. 65, No. 10, pp. 513-522, 2009.
  12. ITU-T Recommendation, "Perceptual Evaluation of Speech Quality(PESQ) : An objective method for end-to-end speech quality assessment of narrow-band telephone networks and speech codes," pp, 862, 2001.
  13. Lado Kakuhari, Hiroyuki Hashimoto, Kenichi Teral, "Development of a loudspeaker system with a unidirectional radiation pattern in a speech frequency range," Proc. 106th Convention of Audio Engineering Society, #4867, 1999.