public void InsertNewFrame_FramesNotBeNull()
        {
            var collection = new ImageFrameCollection <Rgba32>(10, 10);

            ArgumentNullException ex = Assert.Throws <ArgumentNullException>(() =>
            {
                collection.Insert(1, null);
            });

            Assert.StartsWith("Value cannot be null.", ex.Message);
        }
        public void InsertNewFrame_FramesMustHaveSameSize()
        {
            var collection = new ImageFrameCollection <Rgba32>(10, 10);

            ArgumentException ex = Assert.Throws <ArgumentException>(() =>
            {
                collection.Insert(1, new ImageFrame <Rgba32>(1, 1));
            });

            Assert.StartsWith("Frame must have the same dimensions as the image.", ex.Message);
        }