from PIL import Image
import numpy as np
import matplotlib.pyplot as plt

#Load an image
fname = 'picture1.jpg'
image_grey = Image.open(fname).convert("L")
image_rgb = Image.open(fname).convert("RGB")

arrey_grey = np.asarray(image_grey)
arrey_rgb = np.asarray(image_rgb)

#Get image size
with Image.open('picture1.jpg') as img:
    width, height = img.size

size = width * height

#Plot the uploaded image both grey and rgb
plt.imshow(arrey_grey, cmap='gray')
plt.show()

plt.imshow(arrey_rgb)
plt.show()

#Define numpy arrey for each color channel
matrix_red = np.zeros((256, 4),dtype = object)
matrix_red[:,1] = int(0)
matrix_red[:,2:] = float(0)

matrix_green = np.zeros((256, 4),dtype = object)
matrix_green[:,1] = int(0)
matrix_green[:,2:] = float(0)

matrix_blue = np.zeros((256, 4),dtype = object)
matrix_blue[:,1] = int(0)
matrix_blue[:,2:] = float(0)

# Completing first column with 0-255
for i in range(256):
    matrix_red[i][0] = i
    matrix_green[i][0] = i
    matrix_blue[i][0] = i

# Counting intensity for each color channel
for i in range(width):
    Matrix_Width = arrey_rgb[i]
    for i in range(height):
        Matrix_Height = Matrix_Width[i]
        Red_Value = Matrix_Height[0]
        Green_Value = Matrix_Height[1]
        Blue_Value = Matrix_Height[2]
        for i in range(256):
            if (matrix_red[i][0] == Red_Value):
                matrix_red[i][1] = matrix_red[i][1] + 1
            if (matrix_green[i][0] == Green_Value):
                matrix_green[i][1] = matrix_green[i][1] + 1
            if (matrix_blue[i][0] == Blue_Value):
                matrix_blue[i][1] = matrix_blue[i][1] + 1

# Data for task ahead
Hx = 0
for i in range(256):
    matrix_red[i][2] = matrix_red[i][1] / size
    Hx = (matrix_red[i][2] + matrix_red[i][3]) + Hx
    matrix_red[i][3] = Hx

#Plotting results
Frequencie_Red = np.zeros((256, 1),dtype = object)
Frequencie_Red[:,0] = int(0)

Frequencie_Green = np.zeros((256, 1),dtype = object)
Frequencie_Green[:,0] = int(0)

Frequencie_Blue = np.zeros((256, 1),dtype = object)
Frequencie_Blue[:,0] = int(0)

Intensity = np.zeros((256, 1),dtype = object)
Intensity[:,0] = int(0)

for i in range(256):
    Frequencie_Red[i] = matrix_red[i][1]
    Frequencie_Green[i] = matrix_green[i][1]
    Frequencie_Blue[i] = matrix_blue[i][1]

for i in range(256):
    Intensity[i] = i

pos = Intensity
width = 1.0

ax = plt.axes()
ax.set_xticks(pos + (width / 2))
ax.set_xticklabels(Intensity)

plt.bar(pos, Frequencie_Red, width, color='r')
plt.show()

plt.bar(pos, Frequencie_Green, width, color='g')
plt.show()

plt.bar(pos, Frequencie_Blue, width, color='b')
plt.show()