2 files changed, 10 insertions, 22 deletions

diff --git a/training/functional.py b/training/functional.py
index 2d582bf..36269f0 100644
--- a/training/functional.py
+++ b/training/functional.py
@@ -253,7 +253,7 @@ def loss_step(
     text_encoder: CLIPTextModel,
     with_prior_preservation: bool,
     prior_loss_weight: float,
-    low_freq_noise: float,
+    noise_offset: float,
     seed: int,
     step: int,
     batch: dict[str, Any],
@@ -268,30 +268,19 @@ def loss_step(
     generator = torch.Generator(device=latents.device).manual_seed(seed + step) if eval else None
 
     # Sample noise that we'll add to the latents
-    noise = torch.randn(
-        latents.shape,
+    offsets = noise_offset * torch.randn(
+        latents.shape[0], 1, 1, 1,
         dtype=latents.dtype,
         layout=latents.layout,
         device=latents.device,
         generator=generator
+    ).expand(latents.shape)
+    noise = torch.normal(
+        mean=offsets,
+        std=1,
+        generator=generator,
     )
 
-    if low_freq_noise != 0:
-        low_freq_factor = low_freq_noise * torch.randn(
-            latents.shape[0], 1, 1, 1,
-            dtype=latents.dtype,
-            layout=latents.layout,
-            device=latents.device,
-            generator=generator
-        )
-        noise = noise * (1 - low_freq_factor) + low_freq_factor * torch.randn(
-            latents.shape[0], latents.shape[1], 1, 1,
-            dtype=latents.dtype,
-            layout=latents.layout,
-            device=latents.device,
-            generator=generator
-        )
-
     # Sample a random timestep for each image
     timesteps = torch.randint(
         0,
@@ -576,7 +565,7 @@ def train(
     global_step_offset: int = 0,
     with_prior_preservation: bool = False,
     prior_loss_weight: float = 1.0,
-    low_freq_noise: float = 0.1,
+    noise_offset: float = 0.2,
     **kwargs,
 ):
     text_encoder, unet, optimizer, train_dataloader, val_dataloader, lr_scheduler, extra = strategy.prepare(
@@ -611,7 +600,7 @@ def train(
         text_encoder,
         with_prior_preservation,
         prior_loss_weight,
-        low_freq_noise,
+        noise_offset,
         seed,
     )
 
diff --git a/training/util.py b/training/util.py
index c8524de..8bd8a83 100644
--- a/training/util.py
+++ b/training/util.py
@@ -1,6 +1,5 @@
 from pathlib import Path
 import json
-import copy
 from typing import Iterable, Any
 from contextlib import contextmanager