Take the XnaFan ImageComparison library to inspectionate the sourcecode as an example for your needs
It reveals the difference between pixels and can compare images with a Similarity coefficient, Here is a basic example of both:
Imports XnaFan.ImageComparison
' ===================================================
' Get percentage difference value between two images:
' ===================================================
Dim img1 As Image = Image.FromFile("C:\Image1.jpg")
Dim img2 As Image = Image.FromFile("C:\Image2.jpg")
Dim PercentageDifference As Single =
ImageTool.PercentageDifference(img1:=img1, img2:=img2, threshold:=3)
MessageBox.Show(String.Format("Percentage Difference: {0}%",
CSng(PercentageDifference * 100I).ToString("n1")))
' ========================================
' Get difference image between two images:
' ========================================
Dim img1 As Image = Image.FromFile("C:\Image1.jpg")
Dim img2 As Image = Image.FromFile("C:\Image2.jpg")
Dim DifferenceBitmap As Bitmap =
ImageTool.GetDifferenceImage(img1:=img1,
img2:=img2,
adjustColorSchemeToMaxDifferenceFound:=True,
absoluteText:=False)
PictureBox1.Image = DifferenceBitmap
If you want something more complex you could use AForge (Imaging) library to do the similarity comparison
This solution is obtained from :
http://stackoverflow.com/users/1248295/elektrostudios[
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