2 files changed, 87 insertions, 0 deletions
diff --git a/extensions-builtin/Lora/network_oft.py b/extensions-builtin/Lora/network_oft.py
new file mode 100644
index 00000000..9ddb175c
--- /dev/null
+++ b/extensions-builtin/Lora/network_oft.py
@@ -0,0 +1,82 @@
+import torch
+import network
+
+
+class ModuleTypeOFT(network.ModuleType):
+    def create_module(self, net: network.Network, weights: network.NetworkWeights):
+        if all(x in weights.w for x in ["oft_blocks"]):
+            return NetworkModuleOFT(net, weights)
+
+        return None
+
+# adapted from https://github.com/kohya-ss/sd-scripts/blob/main/networks/oft.py
+class NetworkModuleOFT(network.NetworkModule):
+    def __init__(self,  net: network.Network, weights: network.NetworkWeights):
+        super().__init__(net, weights)
+
+        self.oft_blocks = weights.w["oft_blocks"]
+        self.alpha = weights.w["alpha"]
+
+        self.dim = self.oft_blocks.shape[0]
+        self.num_blocks = self.dim
+
+        #if type(self.alpha) == torch.Tensor:
+        #    self.alpha = self.alpha.detach().numpy()
+
+        if "Linear" in self.sd_module.__class__.__name__:
+            self.out_dim = self.sd_module.out_features
+        elif "Conv" in self.sd_module.__class__.__name__:
+            self.out_dim = self.sd_module.out_channels
+
+        self.constraint = self.alpha * self.out_dim
+        self.block_size = self.out_dim // self.num_blocks
+
+        self.oft_multiplier = self.multiplier()
+
+        # replace forward method of original linear rather than replacing the module
+        # self.org_forward = self.sd_module.forward
+        # self.sd_module.forward = self.forward
+    
+    def get_weight(self):
+        block_Q = self.oft_blocks - self.oft_blocks.transpose(1, 2)
+        norm_Q = torch.norm(block_Q.flatten())
+        new_norm_Q = torch.clamp(norm_Q, max=self.constraint)
+        block_Q = block_Q * ((new_norm_Q + 1e-8) / (norm_Q + 1e-8))
+        I = torch.eye(self.block_size, device=self.oft_blocks.device).unsqueeze(0).repeat(self.num_blocks, 1, 1)
+        block_R = torch.matmul(I + block_Q, (I - block_Q).inverse())
+
+        block_R_weighted = self.oft_multiplier * block_R + (1 - self.oft_multiplier) * I
+        R = torch.block_diag(*block_R_weighted)
+
+        return R
+
+    def calc_updown(self, orig_weight):
+        oft_blocks = self.oft_blocks.to(orig_weight.device, dtype=orig_weight.dtype)
+        block_Q = oft_blocks - oft_blocks.transpose(1, 2)
+        norm_Q = torch.norm(block_Q.flatten())
+        new_norm_Q = torch.clamp(norm_Q, max=self.constraint)
+        block_Q = block_Q * ((new_norm_Q + 1e-8) / (norm_Q + 1e-8))
+        I = torch.eye(self.block_size, device=oft_blocks.device).unsqueeze(0).repeat(self.num_blocks, 1, 1)
+        block_R = torch.matmul(I + block_Q, (I - block_Q).inverse())
+
+        block_R_weighted = self.oft_multiplier * block_R + (1 - self.oft_multiplier) * I
+        R = torch.block_diag(*block_R_weighted)
+        #R = self.get_weight().to(orig_weight.device, dtype=orig_weight.dtype)
+        # W = R*W_0
+        updown = orig_weight + R
+        output_shape = [R.size(0), orig_weight.size(1)]
+        return self.finalize_updown(updown, orig_weight, output_shape)
+    
+    # def forward(self, x, y=None):
+    #     x = self.org_forward(x)
+    #     if self.oft_multiplier == 0.0:
+    #         return x
+
+    #     R = self.get_weight().to(x.device, dtype=x.dtype)
+    #     if x.dim() == 4:
+    #         x = x.permute(0, 2, 3, 1)
+    #         x = torch.matmul(x, R)
+    #         x = x.permute(0, 3, 1, 2)
+    #     else:
+    #         x = torch.matmul(x, R)
+    #     return x
diff --git a/extensions-builtin/Lora/networks.py b/extensions-builtin/Lora/networks.py
index 60d8dec4..bd1f1b75 100644
--- a/extensions-builtin/Lora/networks.py
+++ b/extensions-builtin/Lora/networks.py
@@ -11,6 +11,7 @@ import network_ia3
 import network_lokr
 import network_full
 import network_norm
+import network_oft
 
 import torch
 from typing import Union
@@ -28,6 +29,7 @@ module_types = [
     network_full.ModuleTypeFull(),
     network_norm.ModuleTypeNorm(),
     network_glora.ModuleTypeGLora(),
+    network_oft.ModuleTypeOFT(),
 ]
 
 
@@ -183,6 +185,9 @@ def load_network(name, network_on_disk):
         elif sd_module is None and "lora_te1_text_model" in key_network_without_network_parts:
             key = key_network_without_network_parts.replace("lora_te1_text_model", "0_transformer_text_model")
             sd_module = shared.sd_model.network_layer_mapping.get(key, None)
+        elif sd_module is None and "oft_unet" in key_network_without_network_parts:
+            key = key_network_without_network_parts.replace("oft_unet", "diffusion_model")
+            sd_module = shared.sd_model.network_layer_mapping.get(key, None)
 
             # some SD1 Loras also have correct compvis keys
             if sd_module is None: