Check out example codes for "c# get pixel color from image". It will help you in understanding the concepts better.

Code Example 1

using System.Drawing;

Bitmap img = new Bitmap("*imagePath*");
for (int i = 0; i < img.Width; i++)
{
    for (int j = 0; j < img.Height; j++)
    {
        Color pixel = img.GetPixel(i,j);
    }
}

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