import numpy as np
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
import sys

orig = mpimg.imread(sys.argv[1])

def rgb2gray(rgb):
    return np.dot(rgb[...,:3], [0.299, 0.587, 0.114])

gray = rgb2gray(orig) 

def plot_image(im):
    plt.imshow(im, cmap = plt.get_cmap('gray'))
    plt.show()

def get_PCA(M, r):
    u, s, vh = np.linalg.svd(M)
    U=np.transpose(np.transpose(u)[0:r])
    Vh=vh[0:r]
    S=np.diag(s[0:r])
    projection = np.matrix(U)*np.matrix(S)*np.matrix(Vh)
    return projection

if sys.argv[2]=='p':
    print(str(len(gray))+'x'+str(len(gray[1])))
    plot_image(gray)
else:
   	plot_image(get_PCA(gray, int(sys.argv[2])))