Image comparison

[Jacob Roman]

If you were to compare images of the same size, you would do something like this:

Option Explicit
 
Private Type Picture_Type
 
    Size As Long
    Width As Long
    Height As Long
 
End Type
 
Private Sub Command1_Click()
    
    Dim Pic(1) As Picture_Type
    
    Dim X As Long, Y As Long
    
    Dim Is_The_Same As Long
    
    Dim Comparison As Single
    
    With Picture1
        
        .BorderStyle = False
        .Picture = LoadPicture("C:\Jacob's Stuff\Pics\Alice.jpg")
        .AutoSize = True
        .AutoRedraw = True
        .ScaleMode = 3
            
    End With
    
    With Picture2
        
        .BorderStyle = False
        .Picture = LoadPicture("C:\Jacob's Stuff\Pics\whiterabbit.jpg")
        .AutoSize = True
        .AutoRedraw = True
        .ScaleMode = 3
        
    End With
    
    With Pic(0)
    
        .Size = Picture1.ScaleWidth * Picture1.ScaleHeight
        .Width = Picture1.ScaleWidth
        .Height = Picture1.ScaleHeight
            
    End With
    
    With Pic(1)
    
        .Size = Picture2.ScaleWidth * Picture1.ScaleHeight
        .Width = Picture2.ScaleWidth
        .Height = Picture2.ScaleHeight
            
    End With
    
    If Pic(0).Size = Pic(1).Size Then
    
        For Y = 0 To Pic(0).Height - 1
        
            For X = 0 To Pic(0).Width - 1
            
                If Picture1.Point(X, Y) = Picture2.Point(X, Y) Then
                
                    Is_The_Same = Is_The_Same + 1
                
                End If
            
            Next X
            
        Next Y
        
        Comparison = (Is_The_Same / Pic(0).Size) * 100
        
        MsgBox "Both images are " & Comparison & "% the same", vbInformation
    
    Else
    
        MsgBox "The pictures are not the same size, so no comparison will be made.", vbCritical
    
    End If