小波变换和小波逆变换的C++实现，令附有测试数据和结果供参照。-Wavelet transform and wavelet inverse transform of the C++ implementation, so that with test data and results for reference.

这个是2D-DWT的函数，是haar小波 c是图像像素矩阵 steps是变换的阶数-This is a function of Haar, is 2D-DWT wavelet C is the image pixel matrix steps is the order of the transformation