Analysis of images using PIL in Python

Question

I found this code:

import PIL
from PIL import Image
from matplotlib import pyplot as plt

im = Image.open('./color_gradient.png')  
w, h = im.size  
colors = im.getcolors(w*h)

def hexencode(rgb):
 r=rgb[0]
 g=rgb[1]
 b=rgb[2]
 return '#%02x%02x%02x' % (r,g,b)

for idx, c in enumerate(colors):
    plt.bar(idx, c[0], color=hexencode(c[1]),edgecolor=hexencode(c[1]))
plot.show()

For the exact link one can look here- Plot image color histogram using matplotlib

My questions are what are the meaning of the axes, and how can I generate a table out these values? I would like to run some statistics, like percent of green, or red in the picture...

Thanks

Answer 1

From the PIL Documentation :

getcolors

im.getcolors() => a list of (count, color) tuples or None

im.getcolors(maxcolors) => a list of (count, color) tuples or None

The Y axis in the referred graph is the pixel count of that colour and the X axis comprises the (unsorted?) list of colours in the graph.