diff --git a/PIL/_binary.py b/PIL/_binary.py
index 51ce45a79..2f5e8ffd4 100644
--- a/PIL/_binary.py
+++ b/PIL/_binary.py
@@ -11,6 +11,8 @@
 # See the README file for information on usage and redistribution.
 #
 
+from struct import unpack, pack
+
 if bytes is str:
     def i8(c):
         return ord(c)
@@ -34,7 +36,7 @@ def i16le(c, o=0):
     c: string containing bytes to convert
     o: offset of bytes to convert in string
     """
-    return i8(c[o]) | (i8(c[o+1]) << 8)
+    return unpack("<H", c[o:o+2])[0]
 
 
 def i32le(c, o=0):
@@ -44,33 +46,31 @@ def i32le(c, o=0):
     c: string containing bytes to convert
     o: offset of bytes to convert in string
     """
-    return (i8(c[o]) | (i8(c[o+1]) << 8) | (i8(c[o+2]) << 16) |
-            (i8(c[o+3]) << 24))
+    return unpack("<I", c[o:o+4])[0]
 
 
 def i16be(c, o=0):
-    return (i8(c[o]) << 8) | i8(c[o+1])
+    return unpack(">H", c[o:o+2])[0]
 
 
 def i32be(c, o=0):
-    return ((i8(c[o]) << 24) | (i8(c[o+1]) << 16) |
-            (i8(c[o+2]) << 8) | i8(c[o+3]))
+    return unpack(">I", c[o:o+4])[0]
 
 
 # Output, le = little endian, be = big endian
 def o16le(i):
-    return o8(i) + o8(i >> 8)
+    return pack("<H", i)
 
 
 def o32le(i):
-    return o8(i) + o8(i >> 8) + o8(i >> 16) + o8(i >> 24)
+    return pack("<I", i)
 
 
 def o16be(i):
-    return o8(i >> 8) + o8(i)
+    return pack(">H", i)
 
 
 def o32be(i):
-    return o8(i >> 24) + o8(i >> 16) + o8(i >> 8) + o8(i)
+    return pack(">I", i)
 
 # End of file
diff --git a/Tests/test_binary.py b/Tests/test_binary.py
new file mode 100644
index 000000000..4d3fb5914
--- /dev/null
+++ b/Tests/test_binary.py
@@ -0,0 +1,28 @@
+from helper import unittest, PillowTestCase
+
+from PIL import _binary
+
+class TestBinary(PillowTestCase):
+
+    def test_standard(self):
+        self.assertEqual(_binary.i8(b'*'), 42)
+        self.assertEqual(_binary.o8(42), b'*')
+
+    def test_little_endian(self):
+        self.assertEqual(_binary.i16le(b'\xff\xff\x00\x00'), 65535)
+        self.assertEqual(_binary.i32le(b'\xff\xff\x00\x00'), 65535)
+        
+        self.assertEqual(_binary.o16le(65535), b'\xff\xff')
+        self.assertEqual(_binary.o32le(65535), b'\xff\xff\x00\x00')
+
+    def test_big_endian(self):
+        self.assertEqual(_binary.i16be(b'\x00\x00\xff\xff'), 0)
+        self.assertEqual(_binary.i32be(b'\x00\x00\xff\xff'), 65535)
+        
+        self.assertEqual(_binary.o16be(65535), b'\xff\xff')
+        self.assertEqual(_binary.o32be(65535), b'\x00\x00\xff\xff')
+
+if __name__ == '__main__':
+    unittest.main()
+
+# End of file
\ No newline at end of file