added the option for overlap

Author: alexlib

openpiv/test/test_windef.py

@@ -184,11 +184,9 @@ def test_multi_pass_lin():
 
 def test_simple_multipass():
     """ Test simple multipass """
-    # windowsizes = (64, 32, 16)
     x, y, u, v, s2n = windef.simple_multipass(
         frame_a,
-        frame_b,
-        #windowsizes
+        frame_b
     )
     print("simple multipass\n")
     print(u[:2,:2],v[:2,:2])
@@ -200,5 +198,15 @@ def test_simple_multipass():
     assert np.allclose(u, shift_u, atol=threshold)
     assert np.allclose(v, -shift_v, atol=threshold)
 
+
+   # windowsizes = (64, 32, 16)
+    x, y, u, v, s2n = windef.simple_multipass(
+        frame_a,
+        frame_b,
+        windows = (32,16)
+    )
+    assert np.allclose(u, shift_u, atol=threshold)
+    assert np.allclose(v, -shift_v, atol=threshold)
+
     # the second condition is to check if the multipass is done.
     # It need's a little numerical inaccuracy.

openpiv/windef.py

@@ -21,14 +21,16 @@
 from openpiv import smoothn
 from skimage.util import invert
 
-def simple_multipass(frame_a, frame_b, windows = (64, 32, 16)):
+def simple_multipass(frame_a, frame_b, windows = None):
     """ Simple windows deformation multipass run with 
     default settings
     """
-    settings = Settings()
+    settings = Settings() # default, see below
 
-    settings.num_iterations = len(windows)
-    settings.windowsizes = windows
+    if windows is not None:
+        settings.num_iterations = len(windows)
+        settings.windowsizes = windows
+        settings.overlap = [int(w/2) for w in windows]
 
     x, y, u, v, s2n = first_pass(
                                 frame_a,
@@ -43,21 +45,11 @@ def simple_multipass(frame_a, frame_b, windows = (64, 32, 16)):
     if settings.validation_first_pass:
         u, v, mask = validation.typical_validation(u, v, s2n, settings)
 
-    u, v = filters.replace_outliers(
-                u,
-                v,
-                method=settings.filter_method,
-                max_iter=settings.max_filter_iteration,
-                kernel_size=settings.filter_kernel_size
-            )
+    u, v = filters.replace_outliers(u, v)
 
     if settings.smoothn:
-            u, dummy_u1, dummy_u2, dummy_u3 = smoothn.smoothn(
-                u, s=settings.smoothn_p
-            )
-            v, dummy_v1, dummy_v2, dummy_v3 = smoothn.smoothn(
-                v, s=settings.smoothn_p
-            )
+            u,_,_,_ = smoothn.smoothn(u, s=settings.smoothn_p)
+            v,_,_,_ = smoothn.smoothn(v, s=settings.smoothn_p)
     # multipass 
     for i in range(1, settings.num_iterations):