public void ShouldCreateImageWithCorrectContent() { // Arrange const string baseName = "correctContent"; const string fileName = "correctContent.png"; using (var referenceImage = new Bitmap(32, 32)) { for (var x = 0; x < 32; ++x) { for (var y = 0; y < 32; ++y) { referenceImage.SetPixel(x, y, Color.CornflowerBlue); } } for (var i = 0; i < 32; ++i) { referenceImage.SetPixel(i, i, Color.IndianRed); } var sut = new ImageData(referenceImage); // Act sut.Save(baseName); // Assert using (var gdiBitmap = System.Drawing.Image.FromFile(fileName)) { IEqualityComparer comp = new ImageComparer(); Assert.True(comp.Equals(referenceImage, gdiBitmap)); } } }