Python图片压缩：使用奇异值分解

img_compress.py

from scipy.misc import imread
from scipy.linalg import svd
import matplotlib.pyplot as plt
import numpy as np


if __name__ == '__main__':
    img = imread('mm.jpg')
    h, w, c = img.shape

    U0, S0, V0 = svd(img[:, :, 0])
    U1, S1, V1 = svd(img[:, :, 1])
    U2, S2, V2 = svd(img[:, :, 2])
    S0 = np.diag(S0)
    S1 = np.diag(S1)
    S2 = np.diag(S2)

    c0 = (U0[:, :20] @ S0[:20, :20] @ V0[:20, :]).reshape(h, w, 1)
    c1 = (U1[:, :20] @ S1[:20, :20] @ V1[:20, :]).reshape(h, w, 1)
    c2 = (U2[:, :20] @ S2[:20, :20] @ V2[:20, :]).reshape(h, w, 1)
    new_img = np.concatenate((c0, c1, c2), axis=2)

    plt.imshow(np.uint8(new_img))
    plt.show()