Files
asagi4-ComfyUI-Adaptive-Gui…/__init__.py
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Python

import comfy.samplers
import torch
cos = torch.nn.CosineSimilarity(dim=1)
class AdaptiveGuider(comfy.samplers.CFGGuider):
threshold_timestep = 0
uz_scale = 0.0
def set_cfg(self, cfg):
self.cfg = cfg
def set_threshold(self, threshold):
self.threshold = threshold
def set_uncond_zero_scale(self, scale):
self.uz_scale = scale
def zero_cond(self, args):
cond = args["cond_denoised"]
x = args["input"]
x -= x.mean()
cond -= cond.mean()
return x - (cond / cond.std() ** 0.5) * self.uz_scale
def predict_noise(self, x, timestep, model_options={}, seed=None):
cond = self.conds.get("positive")
uncond = self.conds.get("negative")
ts = timestep[0].item()
if self.threshold_timestep > ts:
if self.uz_scale > 0.0:
model_options = model_options.copy()
model_options["sampler_cfg_function"] = self.zero_cond
return comfy.samplers.sampling_function(
self.inner_model, x, timestep, uncond, cond, 1.0, model_options=model_options, seed=seed
)
self.threshold_timestep = 0
uncond_pred, cond_pred = comfy.samplers.calc_cond_batch(
self.inner_model, [uncond, cond], x, timestep, model_options
)
if not self.threshold >= 1.0:
# Is this reshape correct? It at least gives a scalar value...
sim = cos(cond_pred.reshape(1, -1), uncond_pred.reshape(1, -1)).item()
if sim >= self.threshold:
print("AdaptiveGuidance: Cosine similarity", sim, "exceeds threshold, setting CFG to 1.0")
self.threshold_timestep = ts
return comfy.samplers.cfg_function(
self.inner_model,
cond_pred,
uncond_pred,
self.cfg,
x,
timestep,
model_options=model_options,
cond=cond,
uncond=uncond,
)
class AdaptiveGuidance:
@classmethod
def INPUT_TYPES(s):
return {
"required": {
"model": ("MODEL",),
"positive": ("CONDITIONING",),
"negative": ("CONDITIONING",),
"threshold": ("FLOAT", {"default": 0.990, "min": 0.90, "max": 1.0, "step": 0.001, "round": 0.001}),
"cfg": ("FLOAT", {"default": 8.0, "min": 0.0, "max": 100.0, "step": 0.1, "round": 0.01}),
},
"optional": {"uncond_zero_scale": ("FLOAT", {"default": 0.0, "max": 2.0, "step": 0.01})},
}
RETURN_TYPES = ("GUIDER",)
FUNCTION = "patch"
CATEGORY = "sampling/custom_sampling/guiders"
def patch(self, model, positive, negative, threshold, cfg, uncond_zero_scale=0.0):
g = AdaptiveGuider(model)
g.set_conds(positive, negative)
g.set_threshold(threshold)
g.set_uncond_zero_scale(uncond_zero_scale)
g.set_cfg(cfg)
return (g,)
NODE_CLASS_MAPPINGS = {"AdaptiveGuidance": AdaptiveGuidance}