diff --git a/tests/python_tests/webp_encoding_test.py b/tests/python_tests/webp_encoding_test.py
index 933bb238c..ed6e57745 100644
--- a/tests/python_tests/webp_encoding_test.py
+++ b/tests/python_tests/webp_encoding_test.py
@@ -64,91 +64,97 @@ if mapnik.has_webp():
 
     def test_expected_encodings():
         fails = []
-        for opt in opts:
-            im = mapnik.Image(256,256)
-            expected = gen_filepath('blank',opt)
-            actual = os.path.join(tmp_dir,os.path.basename(expected))
-            if generate or not os.path.exists(expected):
-                print 'generating expected image %s' % expected
-                im.save(expected,opt)
-            im.save(actual,opt)
-            try:
-                expected_bytes = mapnik.Image.open(expected).tostring()
-            except RuntimeError:
-                # this will happen if libweb is old, since it cannot open images created by more recent webp
-                print 'warning, cannot open webp expected image (your libwebp is likely too old)'
-                continue
-            if mapnik.Image.open(actual).tostring() != expected_bytes:
-                fails.append('%s (actual) not == to %s (expected)' % (actual,expected))
+        try:
+            for opt in opts:
+                im = mapnik.Image(256,256)
+                expected = gen_filepath('blank',opt)
+                actual = os.path.join(tmp_dir,os.path.basename(expected))
+                if generate or not os.path.exists(expected):
+                    print 'generating expected image %s' % expected
+                    im.save(expected,opt)
+                im.save(actual,opt)
+                try:
+                    expected_bytes = mapnik.Image.open(expected).tostring()
+                except RuntimeError:
+                    # this will happen if libweb is old, since it cannot open images created by more recent webp
+                    print 'warning, cannot open webp expected image (your libwebp is likely too old)'
+                    continue
+                if mapnik.Image.open(actual).tostring() != expected_bytes:
+                    fails.append('%s (actual) not == to %s (expected)' % (actual,expected))
 
-        for opt in opts:
-            im = mapnik.Image(256,256)
-            im.background = mapnik.Color('green')
-            expected = gen_filepath('solid',opt)
-            actual = os.path.join(tmp_dir,os.path.basename(expected))
-            if generate or not os.path.exists(expected):
-                print 'generating expected image %s' % expected
-                im.save(expected,opt)
-            im.save(actual,opt)
-            try:
-                expected_bytes = mapnik.Image.open(expected).tostring()
-            except RuntimeError:
-                # this will happen if libweb is old, since it cannot open images created by more recent webp
-                print 'warning, cannot open webp expected image (your libwebp is likely too old)'
-                continue
-            if mapnik.Image.open(actual).tostring() != expected_bytes:
-                fails.append('%s (actual) not == to %s (expected)' % (actual,expected))
+            for opt in opts:
+                im = mapnik.Image(256,256)
+                im.background = mapnik.Color('green')
+                expected = gen_filepath('solid',opt)
+                actual = os.path.join(tmp_dir,os.path.basename(expected))
+                if generate or not os.path.exists(expected):
+                    print 'generating expected image %s' % expected
+                    im.save(expected,opt)
+                im.save(actual,opt)
+                try:
+                    expected_bytes = mapnik.Image.open(expected).tostring()
+                except RuntimeError:
+                    # this will happen if libweb is old, since it cannot open images created by more recent webp
+                    print 'warning, cannot open webp expected image (your libwebp is likely too old)'
+                    continue
+                if mapnik.Image.open(actual).tostring() != expected_bytes:
+                    fails.append('%s (actual) not == to %s (expected)' % (actual,expected))
 
-        for opt in opts:
-            im = mapnik.Image.open('images/support/transparency/aerial_rgba.png')
-            expected = gen_filepath('aerial_rgba',opt)
-            actual = os.path.join(tmp_dir,os.path.basename(expected))
-            if generate or not os.path.exists(expected):
-                print 'generating expected image %s' % expected
-                im.save(expected,opt)
-            im.save(actual,opt)
-            try:
-                expected_bytes = mapnik.Image.open(expected).tostring()
-            except RuntimeError:
-                # this will happen if libweb is old, since it cannot open images created by more recent webp
-                print 'warning, cannot open webp expected image (your libwebp is likely too old)'
-                continue
-            if mapnik.Image.open(actual).tostring() != expected_bytes:
-                fails.append('%s (actual) not == to %s (expected)' % (actual,expected))
-        # disabled to avoid failures on ubuntu when using old webp packages
-        #eq_(fails,[],'\n'+'\n'.join(fails))
+            for opt in opts:
+                im = mapnik.Image.open('images/support/transparency/aerial_rgba.png')
+                expected = gen_filepath('aerial_rgba',opt)
+                actual = os.path.join(tmp_dir,os.path.basename(expected))
+                if generate or not os.path.exists(expected):
+                    print 'generating expected image %s' % expected
+                    im.save(expected,opt)
+                im.save(actual,opt)
+                try:
+                    expected_bytes = mapnik.Image.open(expected).tostring()
+                except RuntimeError:
+                    # this will happen if libweb is old, since it cannot open images created by more recent webp
+                    print 'warning, cannot open webp expected image (your libwebp is likely too old)'
+                    continue
+                if mapnik.Image.open(actual).tostring() != expected_bytes:
+                    fails.append('%s (actual) not == to %s (expected)' % (actual,expected))
+            # disabled to avoid failures on ubuntu when using old webp packages
+            #eq_(fails,[],'\n'+'\n'.join(fails))
+        except RuntimeError, e:
+            print e
 
     def test_transparency_levels():
-        # create partial transparency image
-        im = mapnik.Image(256,256)
-        im.background = mapnik.Color('rgba(255,255,255,.5)')
-        c2 = mapnik.Color('rgba(255,255,0,.2)')
-        c3 = mapnik.Color('rgb(0,255,255)')
-        for y in range(0,im.height()/2):
-            for x in range(0,im.width()/2):
-                im.set_pixel(x,y,c2)
-        for y in range(im.height()/2,im.height()):
-            for x in range(im.width()/2,im.width()):
-                im.set_pixel(x,y,c3)
-
-        t0 = tmp_dir + 'white0-actual.webp'
-
-        # octree
-        format = 'webp'
-        expected = 'images/support/transparency/white0.webp'
-        if generate or not os.path.exists(expected):
-            im.save('images/support/transparency/white0.webp')
-        im.save(t0,format)
-        im_in = mapnik.Image.open(t0)
-        t0_len = len(im_in.tostring(format))
         try:
-            expected_bytes = mapnik.Image.open(expected).tostring(format)
-        except RuntimeError:
-            # this will happen if libweb is old, since it cannot open images created by more recent webp
-            print 'warning, cannot open webp expected image (your libwebp is likely too old)'
-            return
-        # disabled to avoid failures on ubuntu when using old webp packages
-        #eq_(t0_len,len(expected_bytes))
+            # create partial transparency image
+            im = mapnik.Image(256,256)
+            im.background = mapnik.Color('rgba(255,255,255,.5)')
+            c2 = mapnik.Color('rgba(255,255,0,.2)')
+            c3 = mapnik.Color('rgb(0,255,255)')
+            for y in range(0,im.height()/2):
+                for x in range(0,im.width()/2):
+                    im.set_pixel(x,y,c2)
+            for y in range(im.height()/2,im.height()):
+                for x in range(im.width()/2,im.width()):
+                    im.set_pixel(x,y,c3)
+
+            t0 = tmp_dir + 'white0-actual.webp'
+
+            # octree
+            format = 'webp'
+            expected = 'images/support/transparency/white0.webp'
+            if generate or not os.path.exists(expected):
+                im.save('images/support/transparency/white0.webp')
+            im.save(t0,format)
+            im_in = mapnik.Image.open(t0)
+            t0_len = len(im_in.tostring(format))
+            try:
+                expected_bytes = mapnik.Image.open(expected).tostring(format)
+            except RuntimeError:
+                # this will happen if libweb is old, since it cannot open images created by more recent webp
+                print 'warning, cannot open webp expected image (your libwebp is likely too old)'
+                return
+            # disabled to avoid failures on ubuntu when using old webp packages
+            #eq_(t0_len,len(expected_bytes))
+        except RuntimeError, e:
+            print e
 
 
 if __name__ == "__main__":