Merge pull request #2419 from hugovk/numpy-zero-size

Fix division by zero when creating 0x0 image from numpy array

PIL/Image.py

@@ -2036,7 +2036,7 @@ def _check_size(size):
     if len(size) != 2:
         raise ValueError("Size must be a tuple of length 2")
     if size[0] < 0 or size[1] < 0:
-        raise ValueError("Width and Height must be => 0")
+        raise ValueError("Width and height must be >= 0")
 
     return True
 

Tests/test_numpy.py

@@ -204,6 +204,14 @@ class TestNumpy(PillowTestCase):
 
         self.assertEqual(len(im.getdata()), len(arr))
 
+    def test_zero_size(self):
+        # Shouldn't cause floating point exception
+        # See https://github.com/python-pillow/Pillow/issues/2259
+
+        im = Image.fromarray(numpy.empty((0, 0), dtype=numpy.uint8))
+
+        self.assertEqual(im.size, (0, 0))
+
 
 if __name__ == '__main__':
     unittest.main()

map.c

@@ -342,7 +342,7 @@ PyImaging_MapBuffer(PyObject* self, PyObject* args)
             stride = xsize * 4;
     }
 
-    if (ysize > INT_MAX / stride) {
+    if (stride > 0 && ysize > INT_MAX / stride) {
         PyErr_SetString(PyExc_MemoryError, "Integer overflow in ysize");
         return NULL;
     }