private void CompareTestImgs(TestImage t1, TestImage t2)
{
t1.Should().BeEquivalentTo(t2, opt => opt.Excluding(i => i.Img));
var mat = t1.Img;
mat.Rows.Should().Be(t2.Img.Rows);
mat.Cols.Should().Be(t2.Img.Cols);
}