Fast Graphic Visualization of Frequency Response for Audio Equalizer

This paper proposes a new method for fast graphic visualization of accurate frequency response of audio equalizer (EQ). When a logarithmic frequency scale is used, a frequency response in high resolution is required for accurate low-band frequency response. However, the high-resolution frequency response requires a huge amount of computational load, which makes the real-time graphic visualization of frequency response impossible. In order to solve the problem of computational load, the proposed method utilizes a low-resolution virtual frequency response in the mid band. It first computes the virtual frequency response of each filter of EQ in the mid band, and then moves it to the target band so that the result corresponds to the desired filter response. Then, it determines the final frequency response of EQ by combining all filter responses. The experiments confirm that the proposed method provides the frequency response of EQ which has an equivalent shape to that computed in high frequency resolution with huge computational load.

[1]  Keiichi Tokuda,et al.  Minimum generation error training by using original spectrum as reference for log spectral distortion measure , 2009, 2009 IEEE International Conference on Acoustics, Speech and Signal Processing.

[2]  Matti Karjalainen,et al.  Modeling of reflections and air absorption in acoustical spaces a digital filter design approach , 1997, Proceedings of 1997 Workshop on Applications of Signal Processing to Audio and Acoustics.

[3]  Hirokazu Kameoka,et al.  A Real-time Equalizer of Harmonic and Percussive Components in Music Signals , 2008, ISMIR.

[4]  Julius O. Smith,et al.  Bark and ERB bilinear transforms , 1999, IEEE Trans. Speech Audio Process..

[5]  Shoji Makino,et al.  Multiple-point equalization of room transfer functions by using common acoustical poles , 1997, IEEE Trans. Speech Audio Process..

[6]  Sanjit K. Mitra,et al.  Tunable digital frequency response equalization filters , 1987, IEEE Trans. Acoust. Speech Signal Process..

[7]  김경석,et al.  복잡도를 개선한 Digital Down Converter 시스템 , 2010 .