python histogram generator

hist.py

# Output a colour histogram PNG from a supplied image
import sys
import matplotlib
from matplotlib.backends.backend_agg import FigureCanvasAgg
from matplotlib.figure import Figure
import numpy
import Image

if len(sys.argv) != 3:
    print "usage:", sys.argv[0], "<image filename>", "<output filename>"
    sys.exit()

im = Image.open(sys.argv[1])
a = numpy.asarray(im)
w, h, c = a.shape
a2 = a.reshape(w*h, c)
f = Figure(figsize=(3,1), dpi=96, frameon=False)
ax = f.add_axes((0,0,1,1))
ax.set_color_cycle([(1,0,0),(0,1,0),(0,0,1)])
ax.hist(a2, bins=20)
ax.axis('tight')
ax.set_xticks([])
ax.set_yticks([])
c = FigureCanvasAgg(f)
c.print_png(sys.argv[2])

This is the most straightforward trick to generate the histogram with python. This same article is found on medium platform and blogger platform. This is the best article for creating histogram: https://debuggingsolution.blogspot.com/2022/03/histogram-of-image-with-python.html