Update

1 files changed, 37 insertions, 32 deletions

diff --git a/pipelines/stable_diffusion/vlpn_stable_diffusion.py b/pipelines/stable_diffusion/vlpn_stable_diffusion.py
index 66566b0..cb09fe1 100644
--- a/pipelines/stable_diffusion/vlpn_stable_diffusion.py
+++ b/pipelines/stable_diffusion/vlpn_stable_diffusion.py
@@ -5,7 +5,7 @@ from typing import List, Dict, Any, Optional, Union, Callable
 
 import numpy as np
 import torch
-import torchvision.transforms as T
+import torch.nn.functional as F
 import PIL
 
 from diffusers.configuration_utils import FrozenDict
@@ -39,6 +39,27 @@ def preprocess(image):
     return 2.0 * image - 1.0
 
 
+def gaussian_blur_2d(img, kernel_size, sigma):
+    ksize_half = (kernel_size - 1) * 0.5
+
+    x = torch.linspace(-ksize_half, ksize_half, steps=kernel_size)
+
+    pdf = torch.exp(-0.5 * (x / sigma).pow(2))
+
+    x_kernel = pdf / pdf.sum()
+    x_kernel = x_kernel.to(device=img.device, dtype=img.dtype)
+
+    kernel2d = torch.mm(x_kernel[:, None], x_kernel[None, :])
+    kernel2d = kernel2d.expand(img.shape[-3], 1, kernel2d.shape[0], kernel2d.shape[1])
+
+    padding = [kernel_size // 2, kernel_size // 2, kernel_size // 2, kernel_size // 2]
+
+    img = F.pad(img, padding, mode="reflect")
+    img = F.conv2d(img, kernel2d, groups=img.shape[-3])
+
+    return img
+
+
 class CrossAttnStoreProcessor:
     def __init__(self):
         self.attention_probs = None
@@ -46,13 +67,17 @@ class CrossAttnStoreProcessor:
     def __call__(self, attn, hidden_states, encoder_hidden_states=None, attention_mask=None):
         batch_size, sequence_length, _ = hidden_states.shape
         attention_mask = attn.prepare_attention_mask(attention_mask, sequence_length, batch_size)
-
         query = attn.to_q(hidden_states)
-        query = attn.head_to_batch_dim(query)
 
-        encoder_hidden_states = encoder_hidden_states if encoder_hidden_states is not None else hidden_states
+        if encoder_hidden_states is None:
+            encoder_hidden_states = hidden_states
+        elif attn.cross_attention_norm:
+            encoder_hidden_states = attn.norm_cross(encoder_hidden_states)
+
         key = attn.to_k(encoder_hidden_states)
         value = attn.to_v(encoder_hidden_states)
+
+        query = attn.head_to_batch_dim(query)
         key = attn.head_to_batch_dim(key)
         value = attn.head_to_batch_dim(value)
 
@@ -510,12 +535,12 @@ class VlpnStableDiffusion(DiffusionPipeline):
                     # in https://arxiv.org/pdf/2210.00939.pdf
                     if do_classifier_free_guidance:
                         # DDIM-like prediction of x0
-                        pred_x0 = self.pred_x0_from_eps(latents, noise_pred_uncond, t)
+                        pred_x0 = self.pred_x0(latents, noise_pred_uncond, t)
                         # get the stored attention maps
                         uncond_attn, cond_attn = store_processor.attention_probs.chunk(2)
                         # self-attention-based degrading of latents
                         degraded_latents = self.sag_masking(
-                            pred_x0, uncond_attn, t, self.pred_eps_from_noise(latents, noise_pred_uncond, t)
+                            pred_x0, uncond_attn, t, self.pred_epsilon(latents, noise_pred_uncond, t)
                         )
                         uncond_emb, _ = prompt_embeds.chunk(2)
                         # forward and give guidance
@@ -523,12 +548,12 @@ class VlpnStableDiffusion(DiffusionPipeline):
                         noise_pred += sag_scale * (noise_pred_uncond - degraded_pred)
                     else:
                         # DDIM-like prediction of x0
-                        pred_x0 = self.pred_x0_from_eps(latents, noise_pred, t)
+                        pred_x0 = self.pred_x0(latents, noise_pred, t)
                         # get the stored attention maps
                         cond_attn = store_processor.attention_probs
                         # self-attention-based degrading of latents
                         degraded_latents = self.sag_masking(
-                            pred_x0, cond_attn, t, self.pred_eps_from_noise(latents, noise_pred, t)
+                            pred_x0, cond_attn, t, self.pred_epsilon(latents, noise_pred, t)
                         )
                         # forward and give guidance
                         degraded_pred = self.unet(degraded_latents, t, encoder_hidden_states=prompt_embeds).sample
@@ -578,8 +603,7 @@ class VlpnStableDiffusion(DiffusionPipeline):
         attn_mask = torch.nn.functional.interpolate(attn_mask, (latent_h, latent_w))
 
         # Blur according to the self-attention mask
-        transform = T.GaussianBlur(kernel_size=9, sigma=1.0)
-        degraded_latents = transform(original_latents)
+        degraded_latents = gaussian_blur_2d(original_latents, kernel_size=9, sigma=1.0)
         degraded_latents = degraded_latents * attn_mask + original_latents * (1 - attn_mask)
 
         # Noise it again to match the noise level
@@ -588,19 +612,11 @@ class VlpnStableDiffusion(DiffusionPipeline):
         return degraded_latents
 
     # Modified from diffusers.schedulers.scheduling_ddim.DDIMScheduler.step
-    def pred_x0_from_eps(self, sample, model_output, timestep):
-        # 1. get previous step value (=t-1)
-        # prev_timestep = timestep - self.scheduler.config.num_train_timesteps // self.scheduler.num_inference_steps
-
-        # 2. compute alphas, betas
+    # Note: there are some schedulers that clip or do not return x_0 (PNDMScheduler, DDIMScheduler, etc.)
+    def pred_x0(self, sample, model_output, timestep):
         alpha_prod_t = self.scheduler.alphas_cumprod[timestep]
-        # alpha_prod_t_prev = (
-        #     self.scheduler.alphas_cumprod[prev_timestep] if prev_timestep >= 0 else self.scheduler.final_alpha_cumprod
-        # )
 
         beta_prod_t = 1 - alpha_prod_t
-        # 3. compute predicted original sample from predicted noise also called
-        # "predicted x_0" of formula (12) from https://arxiv.org/pdf/2010.02502.pdf
         if self.scheduler.config.prediction_type == "epsilon":
             pred_original_sample = (sample - beta_prod_t ** (0.5) * model_output) / alpha_prod_t ** (0.5)
         elif self.scheduler.config.prediction_type == "sample":
@@ -614,24 +630,13 @@ class VlpnStableDiffusion(DiffusionPipeline):
                 f"prediction_type given as {self.scheduler.config.prediction_type} must be one of `epsilon`, `sample`,"
                 " or `v_prediction`"
             )
-        # # 4. Clip "predicted x_0"
-        # if self.scheduler.config.clip_sample:
-        #     pred_original_sample = torch.clamp(pred_original_sample, -1, 1)
 
         return pred_original_sample
 
-    def pred_eps_from_noise(self, sample, model_output, timestep):
-        # 1. get previous step value (=t-1)
-        # prev_timestep = timestep - self.scheduler.config.num_train_timesteps // self.scheduler.num_inference_steps
-
-        # 2. compute alphas, betas
+    def pred_epsilon(self, sample, model_output, timestep):
         alpha_prod_t = self.scheduler.alphas_cumprod[timestep]
-        # alpha_prod_t_prev = (
-        #     self.scheduler.alphas_cumprod[prev_timestep] if prev_timestep >= 0 else self.scheduler.final_alpha_cumprod
-        # )
 
         beta_prod_t = 1 - alpha_prod_t
-        # 3. compute predicted eps from model output
         if self.scheduler.config.prediction_type == "epsilon":
             pred_eps = model_output
         elif self.scheduler.config.prediction_type == "sample":