DFT Filter Bank-Based Realization of Low Delay Speech Processing on FPGA
XUE Yi-ming1, CHEN Yao1, HE Ning-ning2, HU Cai-e3, WANG Jian-ping1
1. College of Information and Electrical Engineering, China Agricultural University, Beijing 100083, China;
2. CEC Huada Electronic Design Co., Ltd, Beijing 102209, China;
3. State Grid Beijing Electric Power Company, Beijing 100031, China
Abstract：A low-latency parallel WOLA (Weighted Overlap-add) DFT filter bank design method and its implementation on FPGA are presented.System objective function combined with group delay,asymmetric synthesis window design and iterative algorithm are adopted to reduce the overall system delay during the optimization of DFT filter banks.Calculation delay of FPGA implementation is controlled through multichannel parallel multiplication,multistage pipeline addition chain in key modules of DFT filter banks.The whole design is implemented on a Xilinx FPGA chip of Zynq7020.PESQ test shows that the design can achieve good speech quality.Compared with the serial WOLA structure,the delay of parallel WOLA can be reduced by 1.192 ms at 16 kHz speech sampling rate,with the group delay reduced by 12% and the calculation delay reduced by 29.2%.
[1] SUGIURA R,KAMAMOTO Y,HARADA N,et al.Resolution warped spectral representation for low-delay and low-bit-rate audio coder[J].IEEE/ACM Transactions on Audio,Speech,and Language Processing,2015,23(2):288-299.
[2] SEBASTIAN J,KUMAR M,MURTHY H A.An analysis of the high resolution property of group delay function with applications to audio signal processing[J].Speech Communication,2016,81:42-53.
[3] AGNEW J,THORNTON J M.Just noticeable and objectionable group delays in digital hearing aids[J].Journal of the American Academy of Audiology,2000,11(6):330-336.
[4] ANDERSEN K T,MOONEN M.Adaptive time-frequency analysis for noise reduction in an audio filter bank with low delay[J].IEEE/ACM Transactions on Audio,Speech,and Language Processing,2016,24(4):784-795.
[5] DENG Y,MATHEWS V J,FARHANG-BOROUJENY B.Low-delay nonuniform pseudo-QMF banks with application to speech enhancement[J].IEEE Transactions on Signal Processing,2007,55(5):2110-2121.
[6] SCHNELL M,GEIGER R,SCHMIDT M,et al.Low delay filterbanks for enhanced low delay audio coding[A].Proceedings of IEEE Workshop on Applications of Signal Processing to Audio and Acoustics[C].New Paltz:IEEE,2007.235-238.
[7] SHEIKHZADEH H,BRENNAN R L,WHYTE K R L.Near-end distortion in over-sampled subband adaptive implementation of affine projection algorithm[A].Proceedings of the 12th European Signal Processing Conference[C].Vienna:IEEE,2004.413-416.
[8] 石光明,焦李成.两通道完全重构滤波器组的设计方法:因式分解法[J].电子学报,2001,29(10):1412-1414. SHI Guang-ming,JIAO Li-cheng.Design of PR two-channel filter bank based on factorization[J].Acta Electronica Sinica,2001,29(10):1412-1414.(in Chinese)
[9] 石光明,焦李成.无约束法设计完全重构M带滤波器组[J].电子学报,2002,30(7):970-973. SHI Guang-ming,JIAO Li-cheng.Design for PR M-channel filter banks without constraint[J].Acta Electronica Sinica,2002,30(7):970-973.(in Chinese)
[10] YIU K F C,GRBIC N,NORDHOLM S,et al.Multicriteria design of oversampled uniform DFT filter banks[J].Signal Processing Letters IEEE,2004,11(6):541-544.
[11] HERMANN D,CHAU E,DONY R D,et al.Window based prototype filter design for highly oversampled filter banks in audio applications[A].Proceedings of IEEE International Conference on Acoustics,Speech and Signal Processing[C].Honolulu:IEEE,2007.Ⅱ-405-Ⅱ-408.
[12] MAKUR A,VIJAYAKUMAR A.Theory,design and application of arbitrary order arbitrary delay filterbanks[J].IEEE Transactions on Signal Processing,2014,62(18):4811-4823.
[13] STOCKER C,KURBIEL T,ALFSMANN D,et al.A novel approach to the design of oversampling complex-modulated digital filter banks[A].Proceedings of the 17th European Signal Processing Conference[C].Glasgow:IEEE,2009.2648-2652.
[14] GRBIC N,HAAN J M D,CLAESSON I,et al.Design of oversampled uniform DFT filter banks with reduced inband aliasing and delay constraints[A].Proceedings of the Sixth International,Symposium on Signal Processing and ITS Applications[C].Kuala Lumpur:IEEE,2001.104-107.
[15] DAM H H,NORDHOLM S,CANTONI A,et al.Iterative method for the design of DFT filter bank[J].IEEE Transactions on Circuits and Systems Ⅱ:Express Briefs,2004,5(11):581-586.
[16] 蔡宇,侯朝焕,原建平,等.适用于助听器语音信号处理的DFT调制滤波器组设计[J].声学技术,2012,31(5):517-521. CAI Yu,HOU Chao-huan,YUAN Jian-ping,et al.Design of DFT modulated filter bank for speech processing in hearing aids[J].Technical Acoustics,2012,31(5):517-521.(in Chinese)
[17] CHEN J,LEI Y,PENG Y,et al.Configurable floating-point FFT accelerator on FPGA based multiple-rotation CORDIC[J].Chinese Journal of Electronics,2016,25(6):1063-1070.
[18] IUT-T P.862.3.Application Guide for Objective Quality Measurement Based on Recommendations P.862,P.862.1 and P.862.2[S].
[19] ITU-T P.501.Test Signals for Use in Telephonometry Amendment 3:New Annex D-Speech Files with Male/Female Sentences Prepared for Use with Perceptual Based Objective Speech Quality Prediction[S].
2018, Vol. 46 
