结合PCA的尺度不变特征变换(SIFT)算法，包括压缩比、运行时间和计算复原图像的峰值信噪比,这是第二能量熵的matlab代码。- Combined with PCA scale invariant feature transform (SIFT) algorithm, Including compression ratio, image restoration computing uptime and peak signal to noise ratio, This is the second