Create vtoonify/model/stylegan/op/fused_act.py

vtoonify/model/stylegan/op/fused_act.py

@@ -0,0 +1,34 @@
+import torch
+from torch import nn
+from torch.nn import functional as F
+
+
+class FusedLeakyReLU(nn.Module):
+    def __init__(self, channel, bias=True, negative_slope=0.2, scale=2 ** 0.5):
+        super().__init__()
+
+        if bias:
+            self.bias = nn.Parameter(torch.zeros(channel))
+
+        else:
+            self.bias = None
+
+        self.negative_slope = negative_slope
+        self.scale = scale
+
+    def forward(self, inputs):
+        return fused_leaky_relu(inputs, self.bias, self.negative_slope, self.scale)
+
+
+def fused_leaky_relu(inputs, bias=None, negative_slope=0.2, scale=2 ** 0.5):
+    if bias is not None:
+        rest_dim = [1] * (inputs.ndim - bias.ndim - 1)
+        return (
+            F.leaky_relu(
+                inputs + bias.view(1, bias.shape[0], *rest_dim), negative_slope=negative_slope
+            )
+            * scale
+        )
+
+    else:
+        return F.leaky_relu(inputs, negative_slope=negative_slope) * scale