离散余弦变换，尤其是它的第二种类型，经常被信号处理和图像处理使用，用于对信号和图像(包括静止图像和运动图像)进行有损数据压缩。有测试图片和源代码-Discrete cosine transform, in particular its second type are often used for signal processing and image processing for the signal images (including still images and moving image

快速傅里叶变换函数，对一维信号信息和二维图像信息进行快速傅里叶变换-Fast Fourier transform function, one-dimensional and two-dimensional image information signal information fast Fourier transform

对一个不对称的实序列进行傅里叶分析，将信号分解为奇部和偶部，求出对应的傅里叶变化-Implementation of an asymmetric sequence Fourier analysis, the signal is decomposed into odd and even the Department of the Ministry, find the corresponding Fourier transform