• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.237-240
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• 2000

We have proposed a simple method based on IIR filters for realizing sound image localization. How-ever the nonlinearity of phase characteristics of the IIR filters, which are used for sound image localization, cause decrease of the localization accuracy. In this paper we investigate the influence of phase characteristics on the sound localization. Head-related transfer functions (HRTFs) of a dummy-head are approximated by the IIR filter. We carried out sound image localization experiment with 2-loudspeaker reproduction using the approximated HRTFs. Then the errors which obtained from experiments were compared with the theoretical values which were estimated from the phase shifts of the IIR filters. As a result there was little influence of the nonlinear phase characteristics of the IIR fitters in the localization on the horizontal plane.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.702-705
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• 2002

This paper describes effects of visual information influencing sound localization in the peripheral visual Held under dynamic conditions. Presentation experiments of an audio-visual stimulus were carried out using a movie of a moving patrol car and its siren sound. The tallowing results were obtained: first, the sound image on the timing at the beginning of the presentation was more strongly captured by the visual image than that at the end, i.e., the "beginning effect" was occurred; second, in the peripheral regions, the "beginning effect" was strongly appeared in near the fixation point of eyes.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.5
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• pp.703-708
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• 2011

In this paper, most of the church except for a large church has accommodated many audience to install a balcony floor in a small space. therefore, dead zone and dislocated sound image localization is made due to this under-balcony seats. This paper propose that the problems of dead zone and dislocated sound image localization could be solved using computer simulation in the view of practical side. The economical computer simulation tool, Mapp online that can be found easily was used to the specified church. Installation a sub speaker for dead zone and -10 dB power control of the sub speaker to main speaker power for dislocated sound image localization was proposed. Computer simulation result shows that the value of definition for area was improved from "Normal" to "Very Good" which means about 52% improvement.

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.264-267
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• 2000

This paper describes a real-time 3D sound localization algorithm to be implemented with the use of a Bow power embedded DSP. This algorithm first divides the audible frequency band into three, on the basis of the analysis of the sound reflection and diffraction effects through different media from a certain sound source to human ears, and then in each subband a specific procedure is devised fur the 3D sound localization so as to operate real-time on a low power embedded DSP This algorithm aims at providing a listener with the 3D sound effects through a headphone at low cost and low power consumption.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.1231-1234
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• 1998

Many signal processing methods of widening the sound image for spatial impression have been studied. Most typical methods of widening the sound image are related to the phase shifting and precedence effect. However, these methods are not effective in center sound image. As listener's position moves from center to outside, the center sound image is shifted to the speaker. That is to say, the directional localization of center sound image is unstable. In this paper, we propose a television audio system including center speaker, and analyze the role of center speaker using theory of Makida and precedence effect. In experiments, we confirm the usefulness of the center speaker for the stability of center sound image.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.415-416
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• 2007

HRTF DB, including the information of the sounds which is arrived to our ears, is generally used to make a 3D sound. But it can decline some three-dimensional effects by the confusion between front and back directions due to the non-individual HRTF depending on each listener. In this paper, we propose a new method to use psychoacoustic theory that reduces the confusion of sound image localization. And we make use of an excitation energy by the sense of hearing. This method is brought HRTF spectrum characteristics into relief to draw out the energy ratio about the bark band and control low frequency band. Informal listening tests show that the proposed method improves the front-back sound localization characteristics much better than the conventional methods.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.8C
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• pp.1142-1148
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• 2004

A binaural filtering method using HRTF DB is generally used to make the headphone-based 3D sound. But it can make some confusion between front and back directions or between up and down directions due to the non-individual HRTF depending on each listener. To reduce the confusion of sound image localization, we propose a new method to boost the spectral cue by modifying HRTF spectra with spectrum difference between front and back directions. Informal listening tests show that the proposed method improves the front-back sound localization characteristics much better than the conventional methods

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.51.3-51
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• 2002

3D sound user often finds the results that the sound image appear to originate either inside, or close to, the head when he uses headphone-based binaural system. This phenomenon is called in-head localization(IHL). The main factors were chosen to evaluate externalization performance : individualized HRTFs, near-field HRTF characteristics and reverberation. Direct comparison was conducted among them, especially two factors\ulcorner reverberation and near-field HRTFs.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.5
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• pp.9-17
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• 2010

This paper presents a localization perception of a phantom sound image for ultrahigh-definition TV with respect to various loudspeaker configurations; two-horizontal, two-vertical and triplet loudspeakers. Vector base amplitude panning algorithm with modification for non-equidistant loudspeaker setup is applied to create the phantom sound image. In order to practically study the localization performance in real situation, the listening tests were conducted at the on-axis and off-axis positions of TV in normal listening room. A method of adjustment which can reduce the ambiguity of a perceived angle is exploited to evaluate the angles of octave-band signals. The subjects changed the panning angle until the real sound source and virtually panned source were coincident. A spatial blurring can be measured by examining the differences of the panning angles perceived with respect to each band. The listening tests show that the triplet panning method has better performance than vertical panning in view of perceptual localization and spatial blurring at both on-axis and off-axis positions.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.6
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• pp.671-676
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• 2006

A convolution with HRTF DB and the original sound is generally used to make the method of sound image localization for virtual speaker realization. But it can decline localization by the confusion between up and down or front and back directions due to the non-individual HRTF depending on each listener. In this paper, we study a virtual speaker using a new HRTF, which is grouping the HRTF around the virtual speaker to improve localization between up and down or front and back directions. To effective HRTF grouping, we decide the location and number of HRTF using informal listening test. A performance test result of virtual speaker using the grouped HRTF shows that the proposed method improves the front-back and up-down sound localization characteristics much better than the conventional methods.