基于FPGA的语音信号波形VGA显示方法

在基于FPGA的语谱分析研究与设计中,需要将语音时域波形和语谱分析结果同时显示在VGA屏幕上,而采用一般方法只能在有限的VGA显示区域内显示局部波形,无法将完整的一段语音信号波形显示出来。针对这一问题,提出了一种适合FPGA实现的语音信号波形VGA显示方法。该方法通过分析语音信号的波形特点,以及显示中存在的波形放大、波形缩小两个问题,提出线性插值和保留极值的解决方法,并详细探讨了这两种方法的FPGA硬件实现结构。实验结果表明,该方法能够有效地对语音信号进行正确显示。

FPGA-based speech signal waves displayed on VGA screen

The speech time-domain waveform and spectrogram analysis results displayed simultaneously on the VGA screen are required in the research and design of spectrogram based on FPGA, by general method, only parts of the waveforms can be displayed in the limited VGA display area, and failed to display complete speech signal waveform. To solve this problem, a method suitable to display VGA speech signal waveform based on FPGA implementation is presented in this paper. By analyzing the speech signal wave characteristic and the problems of waveform zooming in/out in the waveform display, we proposed the solution of linear interpolation and keep-extremum method, and discussed the FPGA implementation structure of the two methods in detail. Experiments show that speech signal can be displayed properly by the method.