if err != nil {
		t.Fatal(err)
	}
	if !reflect.DeepEqual(a, b) {
		t.Fatalf("decodings differ:\nnon-interlaced:\n%#v\ninterlaced:\n%#v", a, b)
	}
}

func TestIncompleteIDATOnRowBoundary(t *testing.T) {
	// The following is an invalid 1x2 grayscale PNG image. The header is OK,
	// but the zlib-compressed IDAT payload contains two bytes "\x02\x00",