Refactor model sampling sigmas code. (#10250)

This commit is contained in:
comfyanonymous
2025-10-08 14:49:02 -07:00
committed by GitHub
parent 3e0eb8d33f
commit 6e59934089

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@@ -21,17 +21,23 @@ def rescale_zero_terminal_snr_sigmas(sigmas):
alphas_bar[-1] = 4.8973451890853435e-08
return ((1 - alphas_bar) / alphas_bar) ** 0.5
def reshape_sigma(sigma, noise_dim):
if sigma.nelement() == 1:
return sigma.view(())
else:
return sigma.view(sigma.shape[:1] + (1,) * (noise_dim - 1))
class EPS:
def calculate_input(self, sigma, noise):
sigma = sigma.view(sigma.shape[:1] + (1,) * (noise.ndim - 1))
sigma = reshape_sigma(sigma, noise.ndim)
return noise / (sigma ** 2 + self.sigma_data ** 2) ** 0.5
def calculate_denoised(self, sigma, model_output, model_input):
sigma = sigma.view(sigma.shape[:1] + (1,) * (model_output.ndim - 1))
sigma = reshape_sigma(sigma, model_output.ndim)
return model_input - model_output * sigma
def noise_scaling(self, sigma, noise, latent_image, max_denoise=False):
sigma = sigma.view(sigma.shape[:1] + (1,) * (noise.ndim - 1))
sigma = reshape_sigma(sigma, noise.ndim)
if max_denoise:
noise = noise * torch.sqrt(1.0 + sigma ** 2.0)
else:
@@ -45,12 +51,12 @@ class EPS:
class V_PREDICTION(EPS):
def calculate_denoised(self, sigma, model_output, model_input):
sigma = sigma.view(sigma.shape[:1] + (1,) * (model_output.ndim - 1))
sigma = reshape_sigma(sigma, model_output.ndim)
return model_input * self.sigma_data ** 2 / (sigma ** 2 + self.sigma_data ** 2) - model_output * sigma * self.sigma_data / (sigma ** 2 + self.sigma_data ** 2) ** 0.5
class EDM(V_PREDICTION):
def calculate_denoised(self, sigma, model_output, model_input):
sigma = sigma.view(sigma.shape[:1] + (1,) * (model_output.ndim - 1))
sigma = reshape_sigma(sigma, model_output.ndim)
return model_input * self.sigma_data ** 2 / (sigma ** 2 + self.sigma_data ** 2) + model_output * sigma * self.sigma_data / (sigma ** 2 + self.sigma_data ** 2) ** 0.5
class CONST:
@@ -58,15 +64,15 @@ class CONST:
return noise
def calculate_denoised(self, sigma, model_output, model_input):
sigma = sigma.view(sigma.shape[:1] + (1,) * (model_output.ndim - 1))
sigma = reshape_sigma(sigma, model_output.ndim)
return model_input - model_output * sigma
def noise_scaling(self, sigma, noise, latent_image, max_denoise=False):
sigma = sigma.view(sigma.shape[:1] + (1,) * (noise.ndim - 1))
sigma = reshape_sigma(sigma, noise.ndim)
return sigma * noise + (1.0 - sigma) * latent_image
def inverse_noise_scaling(self, sigma, latent):
sigma = sigma.view(sigma.shape[:1] + (1,) * (latent.ndim - 1))
sigma = reshape_sigma(sigma, latent.ndim)
return latent / (1.0 - sigma)
class X0(EPS):
@@ -80,16 +86,16 @@ class IMG_TO_IMG(X0):
class COSMOS_RFLOW:
def calculate_input(self, sigma, noise):
sigma = (sigma / (sigma + 1))
sigma = sigma.view(sigma.shape[:1] + (1,) * (noise.ndim - 1))
sigma = reshape_sigma(sigma, noise.ndim)
return noise * (1.0 - sigma)
def calculate_denoised(self, sigma, model_output, model_input):
sigma = (sigma / (sigma + 1))
sigma = sigma.view(sigma.shape[:1] + (1,) * (model_output.ndim - 1))
sigma = reshape_sigma(sigma, model_output.ndim)
return model_input * (1.0 - sigma) - model_output * sigma
def noise_scaling(self, sigma, noise, latent_image, max_denoise=False):
sigma = sigma.view(sigma.shape[:1] + (1,) * (noise.ndim - 1))
sigma = reshape_sigma(sigma, noise.ndim)
noise = noise * sigma
noise += latent_image
return noise