From 5d0d4ee98a24b6c72c94635fc5a6e93af2b005bc Mon Sep 17 00:00:00 2001
From: comfyanonymous <121283862+comfyanonymous@users.noreply.github.com>
Date: Mon, 21 Apr 2025 16:36:20 -0700
Subject: [PATCH] Add strength control for vace. (#7717)

---
 comfy/ldm/wan/model.py    | 3 ++-
 comfy/model_base.py       | 3 +++
 comfy_extras/nodes_wan.py | 7 ++++---
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/comfy/ldm/wan/model.py b/comfy/ldm/wan/model.py
index 5e7848bd..4ef86d5f 100644
--- a/comfy/ldm/wan/model.py
+++ b/comfy/ldm/wan/model.py
@@ -582,6 +582,7 @@ class VaceWanModel(WanModel):
         t,
         context,
         vace_context,
+        vace_strength=1.0,
         clip_fea=None,
         freqs=None,
         transformer_options={},
@@ -629,7 +630,7 @@ class VaceWanModel(WanModel):
             ii = self.vace_layers_mapping.get(i, None)
             if ii is not None:
                 c_skip, c = self.vace_blocks[ii](c, x=x_orig, e=e0, freqs=freqs, context=context, context_img_len=context_img_len)
-            x += c_skip
+            x += c_skip * vace_strength
         # head
         x = self.head(x, e)
 
diff --git a/comfy/model_base.py b/comfy/model_base.py
index 04a10152..b0c6a465 100644
--- a/comfy/model_base.py
+++ b/comfy/model_base.py
@@ -1068,6 +1068,9 @@ class WAN21_Vace(WAN21):
             mask = torch.ones(noise_shape, device=noise.device, dtype=noise.dtype)
 
         out['vace_context'] = comfy.conds.CONDRegular(torch.cat([vace_frames.to(noise), mask.to(noise)], dim=1))
+
+        vace_strength = kwargs.get("vace_strength", 1.0)
+        out['vace_strength'] = comfy.conds.CONDConstant(vace_strength)
         return out
 
 
diff --git a/comfy_extras/nodes_wan.py b/comfy_extras/nodes_wan.py
index 19a6cdfa..9dda6459 100644
--- a/comfy_extras/nodes_wan.py
+++ b/comfy_extras/nodes_wan.py
@@ -203,6 +203,7 @@ class WanVaceToVideo:
                              "height": ("INT", {"default": 480, "min": 16, "max": nodes.MAX_RESOLUTION, "step": 16}),
                              "length": ("INT", {"default": 81, "min": 1, "max": nodes.MAX_RESOLUTION, "step": 4}),
                              "batch_size": ("INT", {"default": 1, "min": 1, "max": 4096}),
+                             "strength": ("FLOAT", {"default": 1.0, "min": 0.0, "max": 1000.0, "step": 0.01}),
                 },
                 "optional": {"control_video": ("IMAGE", ),
                              "control_masks": ("MASK", ),
@@ -217,7 +218,7 @@ class WanVaceToVideo:
 
     EXPERIMENTAL = True
 
-    def encode(self, positive, negative, vae, width, height, length, batch_size, control_video=None, control_masks=None, reference_image=None):
+    def encode(self, positive, negative, vae, width, height, length, batch_size, strength, control_video=None, control_masks=None, reference_image=None):
         latent_length = ((length - 1) // 4) + 1
         if control_video is not None:
             control_video = comfy.utils.common_upscale(control_video[:length].movedim(-1, 1), width, height, "bilinear", "center").movedim(1, -1)
@@ -267,8 +268,8 @@ class WanVaceToVideo:
             trim_latent = reference_image.shape[2]
 
         mask = mask.unsqueeze(0)
-        positive = node_helpers.conditioning_set_values(positive, {"vace_frames": control_video_latent, "vace_mask": mask})
-        negative = node_helpers.conditioning_set_values(negative, {"vace_frames": control_video_latent, "vace_mask": mask})
+        positive = node_helpers.conditioning_set_values(positive, {"vace_frames": control_video_latent, "vace_mask": mask, "vace_strength": strength})
+        negative = node_helpers.conditioning_set_values(negative, {"vace_frames": control_video_latent, "vace_mask": mask, "vace_strength": strength})
 
         latent = torch.zeros([batch_size, 16, latent_length, height // 8, width // 8], device=comfy.model_management.intermediate_device())
         out_latent = {}