add support for replicate padding + trick to change symmetric+1 paddi…

…ng in replicate

deel/torchlip/modules/unconstrained.py

@@ -155,8 +155,13 @@ def __init__(
         self.old_padding = padding
         self.old_padding_mode = padding_mode
         if padding_mode.lower() == "symmetric":
-            padding_mode = "zeros"
-            padding = "valid"
+            # symmetric padding of one pixel can be replaced by replicate
+            if (isinstance(padding, int) and padding <= 1) or \
+                (isinstance(padding, tuple) and padding[0] <= 1 and padding[1] <= 1): 
+                    self.old_padding_mode = padding_mode = "replicate"
+            else:
+                padding_mode = "zeros"
+                padding = "valid"
 
         super(PadConv2d, self).__init__(
             in_channels=in_channels,

tests/test_unconstrained_layers.py

@@ -46,17 +46,26 @@ def compare(x, x_ref, index_x=[], index_x_ref=[]):
         np.testing.assert_allclose(x_cropped, np.zeros(x_cropped.shape), 1e-2, 0)
     else:
         np.testing.assert_allclose(
-            x_cropped,
+            x_cropped-
             x_ref[
                 :, :, index_x_ref[0] : index_x_ref[1], index_x_ref[3] : index_x_ref[4]
             ][:, :, :: index_x_ref[2], :: index_x_ref[5]],
+            np.zeros(x_cropped.shape),
             1e-2,
             0,
         )
+        # np.testing.assert_allclose(
+        #     x_cropped,
+        #     x_ref[
+        #         :, :, index_x_ref[0] : index_x_ref[1], index_x_ref[3] : index_x_ref[4]
+        #     ][:, :, :: index_x_ref[2], :: index_x_ref[5]],
+        #     1e-2,
+        #     0,
+        # )
 
 
 @pytest.mark.parametrize(
-    "padding_tested", ["circular", "constant", "symmetric", "reflect"]
+    "padding_tested", ["circular", "constant", "symmetric", "reflect","replicate"]
 )
 @pytest.mark.parametrize(
     "input_shape, batch_size, kernel_size, filters",
@@ -90,15 +99,19 @@ def test_padding(padding_tested, input_shape, batch_size, kernel_size, filters):
     right_x_pad = [p_vert, -p_vert, 1, -p_hor, x_pad_NCHW[3], 1, "right"]
     all_x = [0, x_NCHW[2], 1, 0, x_NCHW[3], 1]
     upper_x = [0, p_vert, 1, 0, x_NCHW[3], 1]
+    upper_x_first = [0, 1, 1, 0, x_NCHW[3], 1]
     upper_x_rev = [0, p_vert, -1, 0, x_NCHW[3], 1]
     upper_x_refl = [1, p_vert + 1, -1, 0, x_NCHW[3], 1]
     lower_x = [-p_vert, x_NCHW[2], 1, 0, x_NCHW[3], 1]
+    lower_x_last = [-1, x_NCHW[2], 1, 0, x_NCHW[3], 1]
     lower_x_rev = [-p_vert, x_NCHW[2], -1, 0, x_NCHW[3], 1]
     lower_x_refl = [-p_vert - 1, x_NCHW[2] - 1, -1, 0, x_NCHW[3], 1]
     left_x = [0, x_NCHW[2], 1, 0, p_hor, 1]
+    left_x_first = [0, x_NCHW[2], 1, 0, 1, 1]
     left_x_rev = [0, x_NCHW[2], 1, 0, p_hor, -1]
     left_x_refl = [0, x_NCHW[2], 1, 1, p_hor + 1, -1]
     right_x = [0, x_NCHW[2], 1, -p_hor, x_NCHW[3], 1]
+    right_x_last = [0, x_NCHW[2], 1, -1, x_NCHW[3], 1]
     right_x_rev = [0, x_NCHW[2], 1, -p_hor, x_NCHW[3], -1]
     right_x_refl = [0, x_NCHW[2], 1, -p_hor - 1, x_NCHW[3] - 1, -1]
     zero_pad = [None, None, None, None]
@@ -108,30 +121,35 @@ def test_padding(padding_tested, input_shape, batch_size, kernel_size, filters):
             "constant": [center_x_pad, all_x],
             "symmetric": [center_x_pad, all_x],
             "reflect": [center_x_pad, all_x],
+            "replicate": [center_x_pad, all_x],
         },
         {
             "circular": [upper_x_pad, lower_x],
             "constant": [upper_x_pad, zero_pad],
             "symmetric": [upper_x_pad, upper_x_rev],
             "reflect": [upper_x_pad, upper_x_refl],
+            "replicate": [upper_x_pad, upper_x_first],
         },
         {
             "circular": [lower_x_pad, upper_x],
             "constant": [lower_x_pad, zero_pad],
             "symmetric": [lower_x_pad, lower_x_rev],
             "reflect": [lower_x_pad, lower_x_refl],
+            "replicate": [lower_x_pad, lower_x_last],
         },
         {
             "circular": [left_x_pad, right_x],
             "constant": [left_x_pad, zero_pad],
             "symmetric": [left_x_pad, left_x_rev],
             "reflect": [left_x_pad, left_x_refl],
+            "replicate": [left_x_pad, left_x_first],
         },
         {
             "circular": [right_x_pad, left_x],
             "constant": [right_x_pad, zero_pad],
             "symmetric": [right_x_pad, right_x_rev],
             "reflect": [right_x_pad, right_x_refl],
+            "replicate": [right_x_pad, right_x_last],
         },
     ]
 
@@ -149,7 +167,7 @@ def test_padding(padding_tested, input_shape, batch_size, kernel_size, filters):
     reason="PadConv2d not available",
 )
 @pytest.mark.parametrize(
-    "padding_tested", ["circular", "constant", "symmetric", "reflect", "same", "valid"]
+    "padding_tested", ["circular", "constant", "symmetric", "reflect", "replicate", "same", "valid"]
 )
 @pytest.mark.parametrize(
     "input_shape, batch_size, kernel_size, filters",
@@ -222,7 +240,7 @@ def test_predict(padding_tested, input_shape, batch_size, kernel_size, filters):
     reason="PadConv2d not available",
 )
 @pytest.mark.parametrize(
-    "padding_tested", ["circular", "constant", "symmetric", "reflect", "same", "valid"]
+    "padding_tested", ["circular", "constant", "symmetric", "reflect", "replicate", "same", "valid"]
 )
 @pytest.mark.parametrize(
     "input_shape, batch_size, kernel_size, filters",

tests/utils_framework.py

@@ -626,6 +626,7 @@ def is_supported_padding(padding):
         "reflect",
         "circular",
         "symmetric",
+        'replicate'
     ]  # "constant",
 
 
@@ -635,7 +636,7 @@ def pad_input(x, padding, kernel_size):
         kernel_size = [kernel_size, kernel_size]
     if padding.lower() in ["same", "valid"]:
         return x
-    elif padding.lower() in ["constant", "reflect", "circular"]:
+    elif padding.lower() in ["constant", "reflect", "circular",'replicate']:
         p_vert, p_hor = kernel_size[0] // 2, kernel_size[1] // 2
         pad_sizes = [
             p_hor,