Update Noise Autocorrelation Loss Function for Pix2PixZero Pipeline (#2942)

* Update Pix2PixZero Auto-correlation Loss

* Add fast inversion tests

* Clarify purpose and mark as deprecated

Fix inversion prompt broadcasting

* Register modules set to `None` in config for `test_save_load_optional_components`

* Update new tests to coordinate with #2953

src/diffusers/pipelines/stable_diffusion/pipeline_stable_diffusion_pix2pix_zero.py

@@ -36,6 +36,7 @@ from ...schedulers.scheduling_ddim_inverse import DDIMInverseScheduler
 from ...utils import (
     PIL_INTERPOLATION,
     BaseOutput,
+    deprecate,
     is_accelerate_available,
     is_accelerate_version,
     logging,
@@ -721,23 +722,31 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
             )
 
         if isinstance(generator, list):
-            init_latents = [
-                self.vae.encode(image[i : i + 1]).latent_dist.sample(generator[i]) for i in range(batch_size)
-            ]
-            init_latents = torch.cat(init_latents, dim=0)
+            latents = [self.vae.encode(image[i : i + 1]).latent_dist.sample(generator[i]) for i in range(batch_size)]
+            latents = torch.cat(latents, dim=0)
         else:
-            init_latents = self.vae.encode(image).latent_dist.sample(generator)
-
-        init_latents = self.vae.config.scaling_factor * init_latents
-
-        if batch_size > init_latents.shape[0] and batch_size % init_latents.shape[0] != 0:
-            raise ValueError(
-                f"Cannot duplicate `image` of batch size {init_latents.shape[0]} to {batch_size} text prompts."
-            )
+            latents = self.vae.encode(image).latent_dist.sample(generator)
+
+        latents = self.vae.config.scaling_factor * latents
+
+        if batch_size != latents.shape[0]:
+            if batch_size % latents.shape[0] == 0:
+                # expand image_latents for batch_size
+                deprecation_message = (
+                    f"You have passed {batch_size} text prompts (`prompt`), but only {latents.shape[0]} initial"
+                    " images (`image`). Initial images are now duplicating to match the number of text prompts. Note"
+                    " that this behavior is deprecated and will be removed in a version 1.0.0. Please make sure to update"
+                    " your script to pass as many initial images as text prompts to suppress this warning."
+                )
+                deprecate("len(prompt) != len(image)", "1.0.0", deprecation_message, standard_warn=False)
+                additional_latents_per_image = batch_size // latents.shape[0]
+                latents = torch.cat([latents] * additional_latents_per_image, dim=0)
+            else:
+                raise ValueError(
+                    f"Cannot duplicate `image` of batch size {latents.shape[0]} to {batch_size} text prompts."
+                )
         else:
-            init_latents = torch.cat([init_latents], dim=0)
-
-        latents = init_latents
+            latents = torch.cat([latents], dim=0)
 
         return latents
 
@@ -759,23 +768,18 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
             )
 
     def auto_corr_loss(self, hidden_states, generator=None):
-        batch_size, channel, height, width = hidden_states.shape
-        if batch_size > 1:
-            raise ValueError("Only batch_size 1 is supported for now")
-
-        hidden_states = hidden_states.squeeze(0)
-        # hidden_states must be shape [C,H,W] now
         reg_loss = 0.0
         for i in range(hidden_states.shape[0]):
-            noise = hidden_states[i][None, None, :, :]
-            while True:
-                roll_amount = torch.randint(noise.shape[2] // 2, (1,), generator=generator).item()
-                reg_loss += (noise * torch.roll(noise, shifts=roll_amount, dims=2)).mean() ** 2
-                reg_loss += (noise * torch.roll(noise, shifts=roll_amount, dims=3)).mean() ** 2
-
-                if noise.shape[2] <= 8:
-                    break
-                noise = F.avg_pool2d(noise, kernel_size=2)
+            for j in range(hidden_states.shape[1]):
+                noise = hidden_states[i : i + 1, j : j + 1, :, :]
+                while True:
+                    roll_amount = torch.randint(noise.shape[2] // 2, (1,), generator=generator).item()
+                    reg_loss += (noise * torch.roll(noise, shifts=roll_amount, dims=2)).mean() ** 2
+                    reg_loss += (noise * torch.roll(noise, shifts=roll_amount, dims=3)).mean() ** 2
+
+                    if noise.shape[2] <= 8:
+                        break
+                    noise = F.avg_pool2d(noise, kernel_size=2)
         return reg_loss
 
     def kl_divergence(self, hidden_states):

tests/pipelines/stable_diffusion/test_stable_diffusion_pix2pix_zero.py

@@ -14,6 +14,8 @@
 # limitations under the License.
 
 import gc
+import random
+import tempfile
 import unittest
 
 import numpy as np
@@ -30,7 +32,7 @@ from diffusers import (
     StableDiffusionPix2PixZeroPipeline,
     UNet2DConditionModel,
 )
-from diffusers.utils import load_numpy, slow, torch_device
+from diffusers.utils import floats_tensor, load_numpy, slow, torch_device
 from diffusers.utils.testing_utils import load_image, load_pt, require_torch_gpu, skip_mps
 
 from ..pipeline_params import TEXT_GUIDED_IMAGE_VARIATION_BATCH_PARAMS, TEXT_GUIDED_IMAGE_VARIATION_PARAMS
@@ -69,6 +71,7 @@ class StableDiffusionPix2PixZeroPipelineFastTests(PipelineTesterMixin, unittest.
             cross_attention_dim=32,
         )
         scheduler = DDIMScheduler()
+        inverse_scheduler = DDIMInverseScheduler()
         torch.manual_seed(0)
         vae = AutoencoderKL(
             block_out_channels=[32, 64],
@@ -101,7 +104,7 @@ class StableDiffusionPix2PixZeroPipelineFastTests(PipelineTesterMixin, unittest.
             "tokenizer": tokenizer,
             "safety_checker": None,
             "feature_extractor": None,
-            "inverse_scheduler": None,
+            "inverse_scheduler": inverse_scheduler,
             "caption_generator": None,
             "caption_processor": None,
         }
@@ -122,6 +125,90 @@ class StableDiffusionPix2PixZeroPipelineFastTests(PipelineTesterMixin, unittest.
         }
         return inputs
 
+    def get_dummy_inversion_inputs(self, device, seed=0):
+        dummy_image = floats_tensor((2, 3, 32, 32), rng=random.Random(seed)).to(torch_device)
+        generator = torch.manual_seed(seed)
+
+        inputs = {
+            "prompt": [
+                "A painting of a squirrel eating a burger",
+                "A painting of a burger eating a squirrel",
+            ],
+            "image": dummy_image.cpu(),
+            "num_inference_steps": 2,
+            "guidance_scale": 6.0,
+            "generator": generator,
+            "output_type": "numpy",
+        }
+        return inputs
+
+    def test_save_load_optional_components(self):
+        if not hasattr(self.pipeline_class, "_optional_components"):
+            return
+
+        components = self.get_dummy_components()
+        pipe = self.pipeline_class(**components)
+        pipe.to(torch_device)
+        pipe.set_progress_bar_config(disable=None)
+
+        # set all optional components to None and update pipeline config accordingly
+        for optional_component in pipe._optional_components:
+            setattr(pipe, optional_component, None)
+        pipe.register_modules(**{optional_component: None for optional_component in pipe._optional_components})
+
+        inputs = self.get_dummy_inputs(torch_device)
+        output = pipe(**inputs)[0]
+
+        with tempfile.TemporaryDirectory() as tmpdir:
+            pipe.save_pretrained(tmpdir)
+            pipe_loaded = self.pipeline_class.from_pretrained(tmpdir)
+            pipe_loaded.to(torch_device)
+            pipe_loaded.set_progress_bar_config(disable=None)
+
+        for optional_component in pipe._optional_components:
+            self.assertTrue(
+                getattr(pipe_loaded, optional_component) is None,
+                f"`{optional_component}` did not stay set to None after loading.",
+            )
+
+        inputs = self.get_dummy_inputs(torch_device)
+        output_loaded = pipe_loaded(**inputs)[0]
+
+        max_diff = np.abs(output - output_loaded).max()
+        self.assertLess(max_diff, 1e-4)
+
+    def test_stable_diffusion_pix2pix_zero_inversion(self):
+        device = "cpu"  # ensure determinism for the device-dependent torch.Generator
+        components = self.get_dummy_components()
+        sd_pipe = StableDiffusionPix2PixZeroPipeline(**components)
+        sd_pipe = sd_pipe.to(device)
+        sd_pipe.set_progress_bar_config(disable=None)
+
+        inputs = self.get_dummy_inversion_inputs(device)
+        inputs["image"] = inputs["image"][:1]
+        inputs["prompt"] = inputs["prompt"][:1]
+        image = sd_pipe.invert(**inputs).images
+        image_slice = image[0, -3:, -3:, -1]
+        assert image.shape == (1, 32, 32, 3)
+        expected_slice = np.array([0.4833, 0.4696, 0.5574, 0.5194, 0.5248, 0.5638, 0.5040, 0.5423, 0.5072])
+
+        assert np.abs(image_slice.flatten() - expected_slice).max() < 1e-3
+
+    def test_stable_diffusion_pix2pix_zero_inversion_batch(self):
+        device = "cpu"  # ensure determinism for the device-dependent torch.Generator
+        components = self.get_dummy_components()
+        sd_pipe = StableDiffusionPix2PixZeroPipeline(**components)
+        sd_pipe = sd_pipe.to(device)
+        sd_pipe.set_progress_bar_config(disable=None)
+
+        inputs = self.get_dummy_inversion_inputs(device)
+        image = sd_pipe.invert(**inputs).images
+        image_slice = image[1, -3:, -3:, -1]
+        assert image.shape == (2, 32, 32, 3)
+        expected_slice = np.array([0.6672, 0.5203, 0.4908, 0.4376, 0.4517, 0.5544, 0.4605, 0.4826, 0.5007])
+
+        assert np.abs(image_slice.flatten() - expected_slice).max() < 1e-3
+
     def test_stable_diffusion_pix2pix_zero_default_case(self):
         device = "cpu"  # ensure determinism for the device-dependent torch.Generator
         components = self.get_dummy_components()