实现了在matlab下音频信号的dct(离散余弦)和fft(傅里叶变换)相对matlab工具箱，有快速准确的效果。-Realized the dct (discrete cosine) of the audio signal in matlab fft (Fourier transform) relative matlab toolbox, fast and accurate results.

导入声音文件，进行快速傅里叶变换，得到声音的频谱。(Import audio files, fast Fourier transform, to get the spectrum of sound.)