diff --git a/colorm_test.go b/colorm_test.go
index 0470f5736..ac1612271 100644
--- a/colorm_test.go
+++ b/colorm_test.go
@@ -60,3 +60,83 @@ func TestColorAssign(t *testing.T) {
 		t.Errorf("m2.Element(%d, %d) = %f, want %f", 0, 0, got, want)
 	}
 }
+
+func TestColorTranslate(t *testing.T) {
+	expected := [4][5]float64{
+		{1, 0, 0, 0, 0.5},
+		{0, 1, 0, 0, 1.5},
+		{0, 0, 1, 0, 2.5},
+		{0, 0, 0, 1, 3.5},
+	}
+	m := ColorM{}
+	m.Translate(0.5, 1.5, 2.5, 3.5)
+	for i := 0; i < 4; i++ {
+		for j := 0; j < 5; j++ {
+			got := m.Element(i, j)
+			want := expected[i][j]
+			if want != got {
+				t.Errorf("m.Element(%d, %d) = %f, want %f", i, j, got, want)
+			}
+		}
+	}
+}
+
+func TestColorScale(t *testing.T) {
+	expected := [4][5]float64{
+		{0.5, 0, 0, 0, 0},
+		{0, 1.5, 0, 0, 0},
+		{0, 0, 2.5, 0, 0},
+		{0, 0, 0, 3.5, 0},
+	}
+	m := ColorM{}
+	m.Scale(0.5, 1.5, 2.5, 3.5)
+	for i := 0; i < 4; i++ {
+		for j := 0; j < 5; j++ {
+			got := m.Element(i, j)
+			want := expected[i][j]
+			if want != got {
+				t.Errorf("m.Element(%d, %d) = %f, want %f", i, j, got, want)
+			}
+		}
+	}
+}
+
+func TestColorTranslateAndScale(t *testing.T) {
+	expected := [4][5]float64{
+		{1, 0, 0, 0, 0},
+		{0, 1, 0, 0, 0},
+		{0, 0, 1, 0, 0},
+		{0, 0, 0, 0.5, 0.5},
+	}
+	m := ColorM{}
+	m.Translate(0, 0, 0, 1)
+	m.Scale(1, 1, 1, 0.5)
+	for i := 0; i < 4; i++ {
+		for j := 0; j < 5; j++ {
+			got := m.Element(i, j)
+			want := expected[i][j]
+			if want != got {
+				t.Errorf("m.Element(%d, %d) = %f, want %f", i, j, got, want)
+			}
+		}
+	}
+}
+
+func TestColorMonochrome(t *testing.T) {
+	expected := [4][5]float64{
+		{0.2990, 0.5870, 0.1140, 0, 0},
+		{0.2990, 0.5870, 0.1140, 0, 0},
+		{0.2990, 0.5870, 0.1140, 0, 0},
+		{0, 0, 0, 1, 0},
+	}
+	m := Monochrome()
+	for i := 0; i < 4; i++ {
+		for j := 0; j < 5; j++ {
+			got := m.Element(i, j)
+			want := expected[i][j]
+			if want != got {
+				t.Errorf("m.Element(%d, %d) = %f, want %f", i, j, got, want)
+			}
+		}
+	}
+}