diff --git a/floatimg/image.py b/floatimg/image.py
index 2c01099..9b0022f 100644
--- a/floatimg/image.py
+++ b/floatimg/image.py
@@ -176,6 +176,9 @@ c_fimg_load_from_png = LIB.fimg_load_from_png
 c_fimg_load_from_png.argtypes = (ct.c_char_p, ct.POINTER(C_FloatImg))
 c_fimg_load_from_png.restype = ct.c_int
 
+c_fimg_get_maxvalue = LIB.fimg_get_maxvalue
+c_fimg_get_maxvalue.argtypes = (ct.POINTER(C_FloatImg),)
+c_fimg_get_maxvalue.restype = ct.c_float
 
 ############################################################################################################
 class FloatImg:
@@ -337,6 +340,11 @@ class FloatImg:
             == 0
         )
 
+    #######################################################################################################
+    def maxvalue(self):
+        """return the maximum value for any channel in the image"""
+        return c_fimg_get_maxvalue(self.c_img_p)
+
 
 ###########################################################################################################
 def fileinfos(fname):
diff --git a/tests/maths.py b/tests/maths.py
new file mode 100644
index 0000000..c5b1c15
--- /dev/null
+++ b/tests/maths.py
@@ -0,0 +1,12 @@
+"""test of core functions """
+
+import floatimg
+
+def test_maxvaalue():
+    width = 5
+    height = 5
+
+    img = floatimg.create_rgb(width, height)
+    color = (255.0, 255.0, 255.0)
+    img.put(2,2, color)
+    assert img.maxvalue() == 255.0ls