VB and Pointers: Having problems

Public Function Displayimage(image As Integer(,)) As Bitmap
    Dim i As Integer, j As Integer
    Dim output As New Bitmap(image.GetLength(0), image.GetLength(1))
    Dim bitmapData1 As BitmapData = output.LockBits(New Rectangle(0, 0, image.GetLength(0), image.GetLength(1)), ImageLockMode.[ReadOnly], PixelFormat.Format32bppArgb)
    Dim imagePointer1 As Pointer(Of Byte) = CType(bitmapData1.Scan0, Pointer(Of Byte))
    For i = 0 To bitmapData1.Height - 1
        For j = 0 To bitmapData1.Width - 1
            imagePointer1(0) = CByte(image(j, i))
            imagePointer1(1) = CByte(image(j, i))
            imagePointer1(2) = CByte(image(j, i))
            imagePointer1(3) = 255
            '4 bytes per pixel
            imagePointer1 += 4
        Next
        'end for j
        '4 bytes per pixel
        imagePointer1 += (bitmapData1.Stride - (bitmapData1.Width * 4))
        'end for i
    Next
    'end unsafe
    output.UnlockBits(bitmapData1)
    Return output
    ' col;
End Function