计算多个图像直方图的欧几里德距离

时间:2016-04-29 15:37:24

标签: python python-3.x

好的,这是计算直方图的函数:

def image_histogram():
    from PIL import Image
    import numpy as np
    import glob
    im = Image.open('/Users/Adnan/Desktop/Archive/0.jpg')
    im_vals1 = np.zeros(256)
    im_vals2 = np.zeros(256)
    im_vals3 = np.zeros(256)

    r,g,b = im.split()

    pixels_r = list(r.getdata())
    pixels_g = list(g.getdata())
    pixels_b = list(b.getdata())
    pix_r = np.array(pixels_r)
    pix_g = np.array(pixels_g)
    pix_b = np.array(pixels_b)
    for idx in range (0, len(pix_r)):
        im_vals1[pix_r[idx]] += 1
        im_vals2[pix_g[idx]] += 1
        im_vals3[pix_b[idx]] += 1
    histogram = list(im_vals1) + list(im_vals2) + list(im_vals3)
    return histogram
print(image_histogram())
def euclidean_distance():
    from scipy.spatial import distance
    a = image_histogram()
    b = image_histogram()
    dist = distance.euclidean(a,b)
print(euclidean_distance())

好的,所以这个函数现在计算1个图像的直方图(0.jpg)。我想知道如何用diff图像多次运行这个相同的函数,并将每个图像直方图存储为列表,然后由欧几里德距离函数使用。我猜测某种递归应该做的伎俩,但不知道如何去做,因为我似乎无法在任何地方找到它。

1 个答案:

答案 0 :(得分:3)

从我的计算机视觉课程中,我记得计算两个直方图之间距离的最佳指标之一是卡方距离。

https://stats.stackexchange.com/questions/184101/comparing-two-histograms-using-chi-square-distance

在python中,它可以是sklearn最近邻函数的自定义指标:

def chiSquared(p,q):
    return 0.5*np.sum((p-q)**2/(p+q+1e-6))