Add ddim inversion pix2pix (#2397)

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* Update docs/source/en/_toctree.yml
Co-authored-by: Suraj Patil <surajp815@gmail.com>

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Co-authored-by: Pedro Cuenca <pedro@huggingface.co>

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---------
Co-authored-by: Suraj Patil <surajp815@gmail.com>
Co-authored-by: Pedro Cuenca <pedro@huggingface.co>

docs/source/en/_toctree.yml

@@ -182,6 +182,8 @@
       title: Overview
     - local: api/schedulers/ddim
       title: DDIM
+    - local: api/schedulers/ddim_inverse
+      title: DDIMInverse
     - local: api/schedulers/ddpm
       title: DDPM
     - local: api/schedulers/deis

docs/source/en/api/pipelines/stable_diffusion/pix2pix_zero.mdx

@@ -138,14 +138,15 @@ caption = pipeline.generate_caption(raw_image)
 Then we employ the generated caption and the input image to get the inverted noise: 
 
 ```py 
-inv_latents, inv_image = pipeline.invert(caption, image=raw_image)
+generator = torch.manual_seed(0)
+inv_latents = pipeline.invert(caption, image=raw_image, generator=generator).latents
 ```
 
 Now, generate the image with edit directions: 
 
 ```py
 # See the "Generating source and target embeddings" section below to
-# automate the generation of these captions with a pre-trained model like Flan-T5.
+# automate the generation of these captions with a pre-trained model like Flan-T5 as explained below.
 source_prompts = ["a cat sitting on the street", "a cat playing in the field", "a face of a cat"]
 target_prompts = ["a dog sitting on the street", "a dog playing in the field", "a face of a dog"]
 

docs/source/en/api/schedulers/ddim_inverse.mdx

+<!--Copyright 2023 The HuggingFace Team. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
+the License. You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
+an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+specific language governing permissions and limitations under the License.
+-->
+
+# Inverse Denoising Diffusion Implicit Models (DDIMInverse)
+
+## Overview
+
+This scheduler is the inverted scheduler of [Denoising Diffusion Implicit Models](https://arxiv.org/abs/2010.02502) (DDIM) by Jiaming Song, Chenlin Meng and Stefano Ermon.
+The implementation is mostly based on the DDIM inversion definition of [Null-text Inversion for Editing Real Images using Guided Diffusion Models](https://arxiv.org/pdf/2211.09794.pdf)
+
+## DDIMInverseScheduler
+[[autodoc]] DDIMInverseScheduler

docs/source/en/api/schedulers/overview.mdx

@@ -46,6 +46,7 @@ The following table summarizes all officially supported schedulers, their corres
 | Scheduler | Paper |
 |---|---|
 | [ddim](./ddim) | [**Denoising Diffusion Implicit Models**](https://arxiv.org/abs/2010.02502) |
+| [ddim_inverse](./ddim_inverse) | [**Denoising Diffusion Implicit Models**](https://arxiv.org/abs/2010.02502) |
 | [ddpm](./ddpm) | [**Denoising Diffusion Probabilistic Models**](https://arxiv.org/abs/2006.11239) |
 | [deis](./deis) | [**DEISMultistepScheduler**](https://arxiv.org/abs/2204.13902) |
 | [singlestep_dpm_solver](./singlestep_dpm_solver) | [**Singlestep DPM-Solver**](https://arxiv.org/abs/2206.00927) |

src/diffusers/__init__.py

@@ -67,6 +67,7 @@ else:
         ScoreSdeVePipeline,
     )
     from .schedulers import (
+        DDIMInverseScheduler,
         DDIMScheduler,
         DDPMScheduler,
         DEISMultistepScheduler,

src/diffusers/pipelines/pipeline_utils.py

@@ -929,7 +929,7 @@ class DiffusionPipeline(ConfigMixin):
         if set(components.keys()) != expected_modules:
             raise ValueError(
                 f"{self} has been incorrectly initialized or {self.__class__} is incorrectly implemented. Expected"
-                f" {expected_modules} to be defined, but {components} are defined."
+                f" {expected_modules} to be defined, but {components.keys()} are defined."
             )
 
         return components

src/diffusers/pipelines/stable_diffusion/pipeline_stable_diffusion_pix2pix_zero.py

@@ -13,16 +13,34 @@
 # limitations under the License.
 
 import inspect
+from dataclasses import dataclass
 from typing import Any, Callable, Dict, List, Optional, Union
 
+import numpy as np
 import PIL
 import torch
-from transformers import CLIPFeatureExtractor, CLIPTextModel, CLIPTokenizer
+import torch.nn.functional as F
+from transformers import (
+    BlipForConditionalGeneration,
+    BlipProcessor,
+    CLIPFeatureExtractor,
+    CLIPTextModel,
+    CLIPTokenizer,
+)
 
 from ...models import AutoencoderKL, UNet2DConditionModel
 from ...models.cross_attention import CrossAttention
 from ...schedulers import DDIMScheduler, DDPMScheduler, EulerAncestralDiscreteScheduler, LMSDiscreteScheduler
-from ...utils import is_accelerate_available, logging, randn_tensor, replace_example_docstring
+from ...schedulers.scheduling_ddim_inverse import DDIMInverseScheduler
+from ...utils import (
+    PIL_INTERPOLATION,
+    BaseOutput,
+    is_accelerate_available,
+    is_accelerate_version,
+    logging,
+    randn_tensor,
+    replace_example_docstring,
+)
 from ..pipeline_utils import DiffusionPipeline
 from . import StableDiffusionPipelineOutput
 from .safety_checker import StableDiffusionSafetyChecker
@@ -30,6 +48,24 @@ from .safety_checker import StableDiffusionSafetyChecker
 
 logger = logging.get_logger(__name__)  # pylint: disable=invalid-name
 
+
+@dataclass
+class Pix2PixInversionPipelineOutput(BaseOutput):
+    """
+    Output class for Stable Diffusion pipelines.
+
+    Args:
+        latents (`torch.FloatTensor`)
+            inverted latents tensor
+        images (`List[PIL.Image.Image]` or `np.ndarray`)
+            List of denoised PIL images of length `batch_size` or numpy array of shape `(batch_size, height, width,
+            num_channels)`. PIL images or numpy array present the denoised images of the diffusion pipeline.
+    """
+
+    latents: torch.FloatTensor
+    images: Union[List[PIL.Image.Image], np.ndarray]
+
+
 EXAMPLE_DOC_STRING = """
     Examples:
         ```py
@@ -46,9 +82,7 @@ EXAMPLE_DOC_STRING = """
 
 
         >>> model_ckpt = "CompVis/stable-diffusion-v1-4"
-        >>> pipeline = StableDiffusionPix2PixZeroPipeline.from_pretrained(
-        ...     model_ckpt, conditions_input_image=False, torch_dtype=torch.float16
-        ... )
+        >>> pipeline = StableDiffusionPix2PixZeroPipeline.from_pretrained(model_ckpt, torch_dtype=torch.float16)
         >>> pipeline.scheduler = DDIMScheduler.from_config(pipeline.scheduler.config)
         >>> pipeline.to("cuda")
 
@@ -68,10 +102,94 @@ EXAMPLE_DOC_STRING = """
         ...     num_inference_steps=50,
         ...     cross_attention_guidance_amount=0.15,
         ... ).images
+
         >>> images[0].save("edited_image_dog.png")
         ```
 """
 
+EXAMPLE_INVERT_DOC_STRING = """
+    Examples:
+        ```py
+        >>> import torch
+        >>> from transformers import BlipForConditionalGeneration, BlipProcessor
+        >>> from diffusers import DDIMScheduler, DDIMInverseScheduler, StableDiffusionPix2PixZeroPipeline
+
+        >>> import requests
+        >>> from PIL import Image
+
+        >>> captioner_id = "Salesforce/blip-image-captioning-base"
+        >>> processor = BlipProcessor.from_pretrained(captioner_id)
+        >>> model = BlipForConditionalGeneration.from_pretrained(
+        ...     captioner_id, torch_dtype=torch.float16, low_cpu_mem_usage=True
+        ... )
+
+        >>> sd_model_ckpt = "CompVis/stable-diffusion-v1-4"
+        >>> pipeline = StableDiffusionPix2PixZeroPipeline.from_pretrained(
+        ...     sd_model_ckpt,
+        ...     caption_generator=model,
+        ...     caption_processor=processor,
+        ...     torch_dtype=torch.float16,
+        ...     safety_checker=None,
+        ... )
+
+        >>> pipeline.scheduler = DDIMScheduler.from_config(pipeline.scheduler.config)
+        >>> pipeline.inverse_scheduler = DDIMInverseScheduler.from_config(pipeline.scheduler.config)
+        >>> pipeline.enable_model_cpu_offload()
+
+        >>> img_url = "https://github.com/pix2pixzero/pix2pix-zero/raw/main/assets/test_images/cats/cat_6.png"
+
+        >>> raw_image = Image.open(requests.get(img_url, stream=True).raw).convert("RGB").resize((512, 512))
+        >>> # generate caption
+        >>> caption = pipeline.generate_caption(raw_image)
+
+        >>> # "a photography of a cat with flowers and dai dai daie - daie - daie kasaii"
+        >>> inv_latents = pipeline.invert(caption, image=raw_image).latents
+        >>> # we need to generate source and target embeds
+
+        >>> source_prompts = ["a cat sitting on the street", "a cat playing in the field", "a face of a cat"]
+
+        >>> target_prompts = ["a dog sitting on the street", "a dog playing in the field", "a face of a dog"]
+
+        >>> source_embeds = pipeline.get_embeds(source_prompts)
+        >>> target_embeds = pipeline.get_embeds(target_prompts)
+        >>> # the latents can then be used to edit a real image
+
+        >>> image = pipeline(
+        ...     caption,
+        ...     source_embeds=source_embeds,
+        ...     target_embeds=target_embeds,
+        ...     num_inference_steps=50,
+        ...     cross_attention_guidance_amount=0.15,
+        ...     generator=generator,
+        ...     latents=inv_latents,
+        ...     negative_prompt=caption,
+        ... ).images[0]
+        >>> image.save("edited_image.png")
+        ```
+"""
+
+
+# Copied from diffusers.pipelines.stable_diffusion.pipeline_stable_diffusion_img2img.preprocess
+def preprocess(image):
+    if isinstance(image, torch.Tensor):
+        return image
+    elif isinstance(image, PIL.Image.Image):
+        image = [image]
+
+    if isinstance(image[0], PIL.Image.Image):
+        w, h = image[0].size
+        w, h = map(lambda x: x - x % 8, (w, h))  # resize to integer multiple of 8
+
+        image = [np.array(i.resize((w, h), resample=PIL_INTERPOLATION["lanczos"]))[None, :] for i in image]
+        image = np.concatenate(image, axis=0)
+        image = np.array(image).astype(np.float32) / 255.0
+        image = image.transpose(0, 3, 1, 2)
+        image = 2.0 * image - 1.0
+        image = torch.from_numpy(image)
+    elif isinstance(image[0], torch.Tensor):
+        image = torch.cat(image, dim=0)
+    return image
+
 
 def prepare_unet(unet: UNet2DConditionModel):
     """Modifies the UNet (`unet`) to perform Pix2Pix Zero optimizations."""
@@ -179,13 +297,17 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
             Please, refer to the [model card](https://huggingface.co/runwayml/stable-diffusion-v1-5) for details.
         feature_extractor ([`CLIPFeatureExtractor`]):
             Model that extracts features from generated images to be used as inputs for the `safety_checker`.
-        conditions_input_image (bool):
-            Whether to condition the pipeline with an input image to compute an inverted noise latent.
         requires_safety_checker (bool):
             Whether the pipeline requires a safety checker. We recommend setting it to True if you're using the
             pipeline publicly.
     """
-    _optional_components = ["safety_checker", "feature_extractor"]
+    _optional_components = [
+        "safety_checker",
+        "feature_extractor",
+        "caption_generator",
+        "caption_processor",
+        "inverse_scheduler",
+    ]
 
     def __init__(
         self,
@@ -194,9 +316,11 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
         tokenizer: CLIPTokenizer,
         unet: UNet2DConditionModel,
         scheduler: Union[DDPMScheduler, DDIMScheduler, EulerAncestralDiscreteScheduler, LMSDiscreteScheduler],
-        safety_checker: StableDiffusionSafetyChecker,
         feature_extractor: CLIPFeatureExtractor,
-        conditions_input_image: bool = False,
+        safety_checker: StableDiffusionSafetyChecker,
+        inverse_scheduler: DDIMInverseScheduler,
+        caption_generator: BlipForConditionalGeneration,
+        caption_processor: BlipProcessor,
         requires_safety_checker: bool = True,
     ):
         super().__init__()
@@ -211,16 +335,6 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
                 " information, please have a look at https://github.com/huggingface/diffusers/pull/254 ."
             )
 
-        if conditions_input_image:
-            raise NotImplementedError
-            # logger.info("Loading caption generator since `conditions_input_image` is True.")
-            # checkpoint = "Salesforce/blip-image-captioning-base"
-            # captioner_processor = AutoProcessor.from_pretrained(checkpoint)
-            # captioner = BlipForConditionalGeneration.from_pretrained(checkpoint, dtype=unet.dtype)
-        else:
-            captioner_processor = None
-            captioner = None
-
         if safety_checker is not None and feature_extractor is None:
             raise ValueError(
                 "Make sure to define a feature extractor when loading {self.__class__} if you want to use the safety"
@@ -232,19 +346,15 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
             text_encoder=text_encoder,
             tokenizer=tokenizer,
             unet=unet,
-            _captioner_processor=captioner_processor,
-            _captioner=captioner,
             scheduler=scheduler,
             safety_checker=safety_checker,
             feature_extractor=feature_extractor,
+            caption_processor=caption_processor,
+            caption_generator=caption_generator,
+            inverse_scheduler=inverse_scheduler,
         )
         self.vae_scale_factor = 2 ** (len(self.vae.config.block_out_channels) - 1)
-        self.conditions_input_image = conditions_input_image
-        self.register_to_config(
-            _captioner=captioner,
-            _captioner_processor=captioner_processor,
-            requires_safety_checker=requires_safety_checker,
-        )
+        self.register_to_config(requires_safety_checker=requires_safety_checker)
 
     # Copied from diffusers.pipelines.stable_diffusion.pipeline_stable_diffusion.StableDiffusionPipeline.enable_sequential_cpu_offload
     def enable_sequential_cpu_offload(self, gpu_id=0):
@@ -268,6 +378,30 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
         if self.safety_checker is not None:
             cpu_offload(self.safety_checker, execution_device=device, offload_buffers=True)
 
+    def enable_model_cpu_offload(self, gpu_id=0):
+        r"""
+        Offloads all models to CPU using accelerate, reducing memory usage with a low impact on performance. Compared
+        to `enable_sequential_cpu_offload`, this method moves one whole model at a time to the GPU when its `forward`
+        method is called, and the model remains in GPU until the next model runs. Memory savings are lower than with
+        `enable_sequential_cpu_offload`, but performance is much better due to the iterative execution of the `unet`.
+        """
+        if is_accelerate_available() and is_accelerate_version(">=", "0.17.0.dev0"):
+            from accelerate import cpu_offload_with_hook
+        else:
+            raise ImportError("`enable_model_offload` requires `accelerate v0.17.0` or higher.")
+
+        device = torch.device(f"cuda:{gpu_id}")
+
+        hook = None
+        for cpu_offloaded_model in [self.vae, self.text_encoder, self.unet, self.vae]:
+            _, hook = cpu_offload_with_hook(cpu_offloaded_model, device, prev_module_hook=hook)
+
+        if self.safety_checker is not None:
+            _, hook = cpu_offload_with_hook(self.safety_checker, device, prev_module_hook=hook)
+
+        # We'll offload the last model manually.
+        self.final_offload_hook = hook
+
     @property
     # Copied from diffusers.pipelines.stable_diffusion.pipeline_stable_diffusion.StableDiffusionPipeline._execution_device
     def _execution_device(self):
@@ -467,7 +601,6 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
     def check_inputs(
         self,
         prompt,
-        conditions_input_image,
         image,
         source_embeds,
         target_embeds,
@@ -484,14 +617,6 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
         if source_embeds is None and target_embeds is None:
             raise ValueError("`source_embeds` and `target_embeds` cannot be undefined.")
 
-        if prompt is None and not conditions_input_image:
-            raise ValueError(f"`prompt` cannot be None when `conditions_input_image` is {conditions_input_image}")
-
-        elif prompt is not None and conditions_input_image:
-            raise ValueError(
-                f"`prompt` should not be provided when `conditions_input_image` is {conditions_input_image}"
-            )
-
         if prompt is not None and prompt_embeds is not None:
             raise ValueError(
                 f"Cannot forward both `prompt`: {prompt} and `prompt_embeds`: {prompt_embeds}. Please make sure to"
@@ -504,12 +629,6 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
         elif prompt is not None and (not isinstance(prompt, str) and not isinstance(prompt, list)):
             raise ValueError(f"`prompt` has to be of type `str` or `list` but is {type(prompt)}")
 
-        if conditions_input_image:
-            if image is None:
-                raise ValueError("`image` cannot be None when `conditions_input_image` is True.")
-            elif isinstance(image, (torch.FloatTensor, PIL.Image.Image)):
-                raise ValueError("Invalid image provided. Supported formats: torch.FloatTensor, PIL.Image.Image.}")
-
     #  Copied from diffusers.pipelines.stable_diffusion.pipeline_stable_diffusion.StableDiffusionPipeline.prepare_latents
     def prepare_latents(self, batch_size, num_channels_latents, height, width, dtype, device, generator, latents=None):
         shape = (batch_size, num_channels_latents, height // self.vae_scale_factor, width // self.vae_scale_factor)
@@ -528,14 +647,24 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
         latents = latents * self.scheduler.init_noise_sigma
         return latents
 
-    def generate_caption(self, image, return_image=True):
+    @torch.no_grad()
+    def generate_caption(self, images):
         """Generates caption for a given image."""
-        inputs = self._captioner_processor(images=image, return_tensors="pt")
-        outputs = self._captioner.generate(inputs)
-        caption = self._captioner_processor.batch_deocde(outputs, skip_special_tokens=True)[0]
-        if return_image:
-            return caption, inputs["pixel_values"]
-        else:
+        text = "a photography of"
+
+        prev_device = self.caption_generator.device
+
+        device = self._execution_device
+        inputs = self.caption_processor(images, text, return_tensors="pt").to(
+            device=device, dtype=self.caption_generator.dtype
+        )
+        self.caption_generator.to(device)
+        outputs = self.caption_generator.generate(**inputs, max_new_tokens=128)
+
+        # offload caption generator
+        self.caption_generator.to(prev_device)
+
+        caption = self.caption_processor.batch_decode(outputs, skip_special_tokens=True)[0]
         return caption
 
     def construct_direction(self, embs_source: torch.Tensor, embs_target: torch.Tensor):
@@ -562,6 +691,66 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
 
         return torch.cat(embeds, dim=0).mean(0)[None]
 
+    def prepare_image_latents(self, image, batch_size, dtype, device, generator=None):
+        if not isinstance(image, (torch.Tensor, PIL.Image.Image, list)):
+            raise ValueError(
+                f"`image` has to be of type `torch.Tensor`, `PIL.Image.Image` or list but is {type(image)}"
+            )
+
+        image = image.to(device=device, dtype=dtype)
+
+        if isinstance(generator, list) and len(generator) != batch_size:
+            raise ValueError(
+                f"You have passed a list of generators of length {len(generator)}, but requested an effective batch"
+                f" size of {batch_size}. Make sure the batch size matches the length of the generators."
+            )
+
+        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)
+        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."
+            )
+        else:
+            init_latents = torch.cat([init_latents], dim=0)
+
+        latents = init_latents
+
+        return latents
+
+    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)
+        return reg_loss
+
+    def kl_divergence(self, hidden_states):
+        mean = hidden_states.mean()
+        var = hidden_states.var()
+        return var + mean**2 - 1 - torch.log(var + 1e-7)
+
     @torch.no_grad()
     @replace_example_docstring(EXAMPLE_DOC_STRING)
     def __call__(
@@ -595,8 +784,6 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
             prompt (`str` or `List[str]`, *optional*):
                 The prompt or prompts to guide the image generation. If not defined, one has to pass `prompt_embeds`.
                 instead.
-            image (`PIL.Image.Image`, *optional*):
-                `Image`, or tensor representing an image batch which will be used for conditioning.
             source_embeds (`torch.Tensor`):
                 Source concept embeddings. Generation of the embeddings as per the [original
                 paper](https://arxiv.org/abs/2302.03027). Used in discovering the edit direction.
@@ -670,25 +857,12 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
         # 1. Check inputs. Raise error if not correct
         self.check_inputs(
             prompt,
-            self.conditions_input_image,
             image,
             source_embeds,
             target_embeds,
             callback_steps,
             prompt_embeds,
         )
-        if self.conditions_input_image and prompt_embeds:
-            logger.warning(
-                f"You have set `conditions_input_image` to {self.conditions_input_image} and"
-                " passed `prompt_embeds`. `prompt_embeds` will be ignored. "
-            )
-
-        # 2. Generate a caption for the input image if we are conditioning the
-        # pipeline based on some input image.
-        if self.conditions_input_image:
-            prompt, preprocessed_image = self.generate_caption(image)
-            height, width = preprocessed_image.shape[-2:]
-            logger.info(f"Generated prompt for the input image: {prompt}.")
 
         # 3. Define call parameters
         if prompt is not None and isinstance(prompt, str):
@@ -723,13 +897,6 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
 
         # 5. Generate the inverted noise from the input image or any other image
         # generated from the input prompt.
-        if self.conditions_input_image:
-            # TODO (sayakpaul): Generate this using DDIM inversion.
-            # We need to get the inverted noise from the input image and this requires
-            # us to do a sort of `inverse_step()` in DDIM and then regularize the
-            # noise to enforce the statistical properties of Gaussian.
-            pass
-        else:
         num_channels_latents = self.unet.in_channels
         latents = self.prepare_latents(
             batch_size * num_images_per_prompt,
@@ -852,7 +1019,206 @@ class StableDiffusionPix2PixZeroPipeline(DiffusionPipeline):
         if output_type == "pil":
             edited_image = self.numpy_to_pil(edited_image)
 
+        # Offload last model to CPU
+        if hasattr(self, "final_offload_hook") and self.final_offload_hook is not None:
+            self.final_offload_hook.offload()
+
         if not return_dict:
             return (edited_image, has_nsfw_concept)
 
         return StableDiffusionPipelineOutput(images=edited_image, nsfw_content_detected=has_nsfw_concept)
+
+    @torch.no_grad()
+    @replace_example_docstring(EXAMPLE_INVERT_DOC_STRING)
+    def invert(
+        self,
+        prompt: Optional[str] = None,
+        image: Union[torch.FloatTensor, PIL.Image.Image] = None,
+        num_inference_steps: int = 50,
+        guidance_scale: float = 1,
+        generator: Optional[Union[torch.Generator, List[torch.Generator]]] = None,
+        latents: Optional[torch.FloatTensor] = None,
+        prompt_embeds: Optional[torch.FloatTensor] = None,
+        cross_attention_guidance_amount: float = 0.1,
+        output_type: Optional[str] = "pil",
+        return_dict: bool = True,
+        callback: Optional[Callable[[int, int, torch.FloatTensor], None]] = None,
+        callback_steps: Optional[int] = 1,
+        cross_attention_kwargs: Optional[Dict[str, Any]] = None,
+        lambda_auto_corr: float = 20.0,
+        lambda_kl: float = 20.0,
+        num_reg_steps: int = 5,
+        num_auto_corr_rolls: int = 5,
+    ):
+        r"""
+        Function used to generate inverted latents given a prompt and image.
+
+        Args:
+            prompt (`str` or `List[str]`, *optional*):
+                The prompt or prompts to guide the image generation. If not defined, one has to pass `prompt_embeds`.
+                instead.
+            image (`PIL.Image.Image`, *optional*):
+                `Image`, or tensor representing an image batch which will be used for conditioning.
+            num_inference_steps (`int`, *optional*, defaults to 50):
+                The number of denoising steps. More denoising steps usually lead to a higher quality image at the
+                expense of slower inference.
+            guidance_scale (`float`, *optional*, defaults to 7.5):
+                Guidance scale as defined in [Classifier-Free Diffusion Guidance](https://arxiv.org/abs/2207.12598).
+                `guidance_scale` is defined as `w` of equation 2. of [Imagen
+                Paper](https://arxiv.org/pdf/2205.11487.pdf). Guidance scale is enabled by setting `guidance_scale >
+                1`. Higher guidance scale encourages to generate images that are closely linked to the text `prompt`,
+                usually at the expense of lower image quality.
+            generator (`torch.Generator` or `List[torch.Generator]`, *optional*):
+                One or a list of [torch generator(s)](https://pytorch.org/docs/stable/generated/torch.Generator.html)
+                to make generation deterministic.
+            latents (`torch.FloatTensor`, *optional*):
+                Pre-generated noisy latents, sampled from a Gaussian distribution, to be used as inputs for image
+                generation. Can be used to tweak the same generation with different prompts. If not provided, a latents
+                tensor will ge generated by sampling using the supplied random `generator`.
+            prompt_embeds (`torch.FloatTensor`, *optional*):
+                Pre-generated text embeddings. Can be used to easily tweak text inputs, *e.g.* prompt weighting. If not
+                provided, text embeddings will be generated from `prompt` input argument.
+            cross_attention_guidance_amount (`float`, defaults to 0.1):
+                Amount of guidance needed from the reference cross-attention maps.
+            output_type (`str`, *optional*, defaults to `"pil"`):
+                The output format of the generate image. Choose between
+                [PIL](https://pillow.readthedocs.io/en/stable/): `PIL.Image.Image` or `np.array`.
+            return_dict (`bool`, *optional*, defaults to `True`):
+                Whether or not to return a [`~pipelines.stable_diffusion.StableDiffusionPipelineOutput`] instead of a
+                plain tuple.
+            callback (`Callable`, *optional*):
+                A function that will be called every `callback_steps` steps during inference. The function will be
+                called with the following arguments: `callback(step: int, timestep: int, latents: torch.FloatTensor)`.
+            callback_steps (`int`, *optional*, defaults to 1):
+                The frequency at which the `callback` function will be called. If not specified, the callback will be
+                called at every step.
+            lambda_auto_corr (`float`, *optional*, defaults to 20.0):
+                Lambda parameter to control auto correction
+            lambda_kl (`float`, *optional*, defaults to 20.0):
+                Lambda parameter to control Kullback–Leibler divergence output
+            num_reg_steps (`int`, *optional*, defaults to 5):
+                Number of regularization loss steps
+            num_auto_corr_rolls (`int`, *optional*, defaults to 5):
+                Number of auto correction roll steps
+
+        Examples:
+
+        Returns:
+            [`~pipelines.stable_diffusion.pipeline_stable_diffusion_pix2pix_zero.Pix2PixInversionPipelineOutput`] or
+            `tuple`:
+            [`~pipelines.stable_diffusion.pipeline_stable_diffusion_pix2pix_zero.Pix2PixInversionPipelineOutput`] if
+            `return_dict` is True, otherwise a `tuple. When returning a tuple, the first element is the inverted
+            latents tensor and then second is the corresponding decoded image.
+        """
+        # 1. Define call parameters
+        if prompt is not None and isinstance(prompt, str):
+            batch_size = 1
+        elif prompt is not None and isinstance(prompt, list):
+            batch_size = len(prompt)
+        else:
+            batch_size = prompt_embeds.shape[0]
+        if cross_attention_kwargs is None:
+            cross_attention_kwargs = {}
+
+        device = self._execution_device
+        # here `guidance_scale` is defined analog to the guidance weight `w` of equation (2)
+        # of the Imagen paper: https://arxiv.org/pdf/2205.11487.pdf . `guidance_scale = 1`
+        # corresponds to doing no classifier free guidance.
+        do_classifier_free_guidance = guidance_scale > 1.0
+
+        # 3. Preprocess image
+        image = preprocess(image)
+
+        # 4. Prepare latent variables
+        latents = self.prepare_image_latents(image, batch_size, self.vae.dtype, device, generator)
+
+        # 5. Encode input prompt
+        num_images_per_prompt = 1
+        prompt_embeds = self._encode_prompt(
+            prompt,
+            device,
+            num_images_per_prompt,
+            do_classifier_free_guidance,
+            prompt_embeds=prompt_embeds,
+        )
+
+        # 4. Prepare timesteps
+        self.inverse_scheduler.set_timesteps(num_inference_steps, device=device)
+        timesteps = self.inverse_scheduler.timesteps
+
+        # 6. Rejig the UNet so that we can obtain the cross-attenion maps and
+        # use them for guiding the subsequent image generation.
+        self.unet = prepare_unet(self.unet)
+
+        # 7. Denoising loop where we obtain the cross-attention maps.
+        num_warmup_steps = len(timesteps) - num_inference_steps * self.inverse_scheduler.order
+        with self.progress_bar(total=num_inference_steps - 2) as progress_bar:
+            for i, t in enumerate(timesteps[1:-1]):
+                # expand the latents if we are doing classifier free guidance
+                latent_model_input = torch.cat([latents] * 2) if do_classifier_free_guidance else latents
+                latent_model_input = self.inverse_scheduler.scale_model_input(latent_model_input, t)
+
+                # predict the noise residual
+                noise_pred = self.unet(
+                    latent_model_input,
+                    t,
+                    encoder_hidden_states=prompt_embeds,
+                    cross_attention_kwargs={"timestep": t},
+                ).sample
+
+                # perform guidance
+                if do_classifier_free_guidance:
+                    noise_pred_uncond, noise_pred_text = noise_pred.chunk(2)
+                    noise_pred = noise_pred_uncond + guidance_scale * (noise_pred_text - noise_pred_uncond)
+
+                # regularization of the noise prediction
+                with torch.enable_grad():
+                    for _ in range(num_reg_steps):
+                        if lambda_auto_corr > 0:
+                            for _ in range(num_auto_corr_rolls):
+                                var = torch.autograd.Variable(noise_pred.detach().clone(), requires_grad=True)
+                                l_ac = self.auto_corr_loss(var, generator=generator)
+                                l_ac.backward()
+
+                                grad = var.grad.detach() / num_auto_corr_rolls
+                                noise_pred = noise_pred - lambda_auto_corr * grad
+
+                        if lambda_kl > 0:
+                            var = torch.autograd.Variable(noise_pred.detach().clone(), requires_grad=True)
+
+                            l_kld = self.kl_divergence(var)
+                            l_kld.backward()
+
+                            grad = var.grad.detach()
+                            noise_pred = noise_pred - lambda_kl * grad
+
+                        noise_pred = noise_pred.detach()
+
+                # compute the previous noisy sample x_t -> x_t-1
+                latents = self.inverse_scheduler.step(noise_pred, t, latents).prev_sample
+
+                # call the callback, if provided
+                if i == len(timesteps) - 1 or (
+                    (i + 1) > num_warmup_steps and (i + 1) % self.inverse_scheduler.order == 0
+                ):
+                    progress_bar.update()
+                    if callback is not None and i % callback_steps == 0:
+                        callback(i, t, latents)
+
+        inverted_latents = latents.detach().clone()
+
+        # 8. Post-processing
+        image = self.decode_latents(latents.detach())
+
+        # Offload last model to CPU
+        if hasattr(self, "final_offload_hook") and self.final_offload_hook is not None:
+            self.final_offload_hook.offload()
+
+        # 9. Convert to PIL.
+        if output_type == "pil":
+            image = self.numpy_to_pil(image)
+
+        if not return_dict:
+            return (inverted_latents, image)
+
+        return Pix2PixInversionPipelineOutput(latents=inverted_latents, images=image)

src/diffusers/schedulers/__init__.py

@@ -23,6 +23,7 @@ except OptionalDependencyNotAvailable:
     from ..utils.dummy_pt_objects import *  # noqa F403
 else:
     from .scheduling_ddim import DDIMScheduler
+    from .scheduling_ddim_inverse import DDIMInverseScheduler
     from .scheduling_ddpm import DDPMScheduler
     from .scheduling_deis_multistep import DEISMultistepScheduler
     from .scheduling_dpmsolver_multistep import DPMSolverMultistepScheduler

src/diffusers/schedulers/scheduling_ddim_inverse.py

+# Copyright 2022 The HuggingFace Team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# DISCLAIMER: This code is strongly influenced by https://github.com/pesser/pytorch_diffusion
+# and https://github.com/hojonathanho/diffusion
+import math
+from dataclasses import dataclass
+from typing import List, Optional, Tuple, Union
+
+import numpy as np
+import torch
+
+from diffusers.configuration_utils import ConfigMixin, register_to_config
+from diffusers.schedulers.scheduling_utils import SchedulerMixin
+from diffusers.utils import BaseOutput
+
+
+@dataclass
+# Copied from diffusers.schedulers.scheduling_ddpm.DDPMSchedulerOutput with DDPM->DDIM
+class DDIMSchedulerOutput(BaseOutput):
+    """
+    Output class for the scheduler's step function output.
+
+    Args:
+        prev_sample (`torch.FloatTensor` of shape `(batch_size, num_channels, height, width)` for images):
+            Computed sample (x_{t-1}) of previous timestep. `prev_sample` should be used as next model input in the
+            denoising loop.
+        pred_original_sample (`torch.FloatTensor` of shape `(batch_size, num_channels, height, width)` for images):
+            The predicted denoised sample (x_{0}) based on the model output from the current timestep.
+            `pred_original_sample` can be used to preview progress or for guidance.
+    """
+
+    prev_sample: torch.FloatTensor
+    pred_original_sample: Optional[torch.FloatTensor] = None
+
+
+# Copied from diffusers.schedulers.scheduling_ddpm.betas_for_alpha_bar
+def betas_for_alpha_bar(num_diffusion_timesteps, max_beta=0.999) -> torch.Tensor:
+    """
+    Create a beta schedule that discretizes the given alpha_t_bar function, which defines the cumulative product of
+    (1-beta) over time from t = [0,1].
+
+    Contains a function alpha_bar that takes an argument t and transforms it to the cumulative product of (1-beta) up
+    to that part of the diffusion process.
+
+
+    Args:
+        num_diffusion_timesteps (`int`): the number of betas to produce.
+        max_beta (`float`): the maximum beta to use; use values lower than 1 to
+                     prevent singularities.
+
+    Returns:
+        betas (`np.ndarray`): the betas used by the scheduler to step the model outputs
+    """
+
+    def alpha_bar(time_step):
+        return math.cos((time_step + 0.008) / 1.008 * math.pi / 2) ** 2
+
+    betas = []
+    for i in range(num_diffusion_timesteps):
+        t1 = i / num_diffusion_timesteps
+        t2 = (i + 1) / num_diffusion_timesteps
+        betas.append(min(1 - alpha_bar(t2) / alpha_bar(t1), max_beta))
+    return torch.tensor(betas, dtype=torch.float32)
+
+
+class DDIMInverseScheduler(SchedulerMixin, ConfigMixin):
+    """
+    DDIMInverseScheduler is the reverse scheduler of [`DDIMScheduler`].
+
+    [`~ConfigMixin`] takes care of storing all config attributes that are passed in the scheduler's `__init__`
+    function, such as `num_train_timesteps`. They can be accessed via `scheduler.config.num_train_timesteps`.
+    [`SchedulerMixin`] provides general loading and saving functionality via the [`SchedulerMixin.save_pretrained`] and
+    [`~SchedulerMixin.from_pretrained`] functions.
+
+    For more details, see the original paper: https://arxiv.org/abs/2010.02502
+
+    Args:
+        num_train_timesteps (`int`): number of diffusion steps used to train the model.
+        beta_start (`float`): the starting `beta` value of inference.
+        beta_end (`float`): the final `beta` value.
+        beta_schedule (`str`):
+            the beta schedule, a mapping from a beta range to a sequence of betas for stepping the model. Choose from
+            `linear`, `scaled_linear`, or `squaredcos_cap_v2`.
+        trained_betas (`np.ndarray`, optional):
+            option to pass an array of betas directly to the constructor to bypass `beta_start`, `beta_end` etc.
+        clip_sample (`bool`, default `True`):
+            option to clip predicted sample between -1 and 1 for numerical stability.
+        set_alpha_to_one (`bool`, default `True`):
+            each diffusion step uses the value of alphas product at that step and at the previous one. For the final
+            step there is no previous alpha. When this option is `True` the previous alpha product is fixed to `1`,
+            otherwise it uses the value of alpha at step 0.
+        steps_offset (`int`, default `0`):
+            an offset added to the inference steps. You can use a combination of `offset=1` and
+            `set_alpha_to_one=False`, to make the last step use step 0 for the previous alpha product, as done in
+            stable diffusion.
+        prediction_type (`str`, default `epsilon`, optional):
+            prediction type of the scheduler function, one of `epsilon` (predicting the noise of the diffusion
+            process), `sample` (directly predicting the noisy sample`) or `v_prediction` (see section 2.4
+            https://imagen.research.google/video/paper.pdf)
+    """
+
+    order = 1
+
+    @register_to_config
+    def __init__(
+        self,
+        num_train_timesteps: int = 1000,
+        beta_start: float = 0.0001,
+        beta_end: float = 0.02,
+        beta_schedule: str = "linear",
+        trained_betas: Optional[Union[np.ndarray, List[float]]] = None,
+        clip_sample: bool = True,
+        set_alpha_to_one: bool = True,
+        steps_offset: int = 0,
+        prediction_type: str = "epsilon",
+    ):
+        if trained_betas is not None:
+            self.betas = torch.tensor(trained_betas, dtype=torch.float32)
+        elif beta_schedule == "linear":
+            self.betas = torch.linspace(beta_start, beta_end, num_train_timesteps, dtype=torch.float32)
+        elif beta_schedule == "scaled_linear":
+            # this schedule is very specific to the latent diffusion model.
+            self.betas = (
+                torch.linspace(beta_start**0.5, beta_end**0.5, num_train_timesteps, dtype=torch.float32) ** 2
+            )
+        elif beta_schedule == "squaredcos_cap_v2":
+            # Glide cosine schedule
+            self.betas = betas_for_alpha_bar(num_train_timesteps)
+        else:
+            raise NotImplementedError(f"{beta_schedule} does is not implemented for {self.__class__}")
+
+        self.alphas = 1.0 - self.betas
+        self.alphas_cumprod = torch.cumprod(self.alphas, dim=0)
+
+        # At every step in ddim, we are looking into the previous alphas_cumprod
+        # For the final step, there is no previous alphas_cumprod because we are already at 0
+        # `set_alpha_to_one` decides whether we set this parameter simply to one or
+        # whether we use the final alpha of the "non-previous" one.
+        self.final_alpha_cumprod = torch.tensor(1.0) if set_alpha_to_one else self.alphas_cumprod[0]
+
+        # standard deviation of the initial noise distribution
+        self.init_noise_sigma = 1.0
+
+        # setable values
+        self.num_inference_steps = None
+        self.timesteps = torch.from_numpy(np.arange(0, num_train_timesteps).copy().astype(np.int64))
+
+    def scale_model_input(self, sample: torch.FloatTensor, timestep: Optional[int] = None) -> torch.FloatTensor:
+        """
+        Ensures interchangeability with schedulers that need to scale the denoising model input depending on the
+        current timestep.
+
+        Args:
+            sample (`torch.FloatTensor`): input sample
+            timestep (`int`, optional): current timestep
+
+        Returns:
+            `torch.FloatTensor`: scaled input sample
+        """
+        return sample
+
+    def set_timesteps(self, num_inference_steps: int, device: Union[str, torch.device] = None):
+        """
+        Sets the discrete timesteps used for the diffusion chain. Supporting function to be run before inference.
+
+        Args:
+            num_inference_steps (`int`):
+                the number of diffusion steps used when generating samples with a pre-trained model.
+        """
+
+        if num_inference_steps > self.config.num_train_timesteps:
+            raise ValueError(
+                f"`num_inference_steps`: {num_inference_steps} cannot be larger than `self.config.train_timesteps`:"
+                f" {self.config.num_train_timesteps} as the unet model trained with this scheduler can only handle"
+                f" maximal {self.config.num_train_timesteps} timesteps."
+            )
+
+        self.num_inference_steps = num_inference_steps
+        step_ratio = self.config.num_train_timesteps // self.num_inference_steps
+        # creates integer timesteps by multiplying by ratio
+        # casting to int to avoid issues when num_inference_step is power of 3
+        timesteps = (np.arange(0, num_inference_steps) * step_ratio).round().copy().astype(np.int64)
+        self.timesteps = torch.from_numpy(timesteps).to(device)
+        self.timesteps += self.config.steps_offset
+
+    def step(
+        self,
+        model_output: torch.FloatTensor,
+        timestep: int,
+        sample: torch.FloatTensor,
+        eta: float = 0.0,
+        use_clipped_model_output: bool = False,
+        variance_noise: Optional[torch.FloatTensor] = None,
+        return_dict: bool = True,
+    ) -> Union[DDIMSchedulerOutput, Tuple]:
+        e_t = model_output
+
+        x = sample
+        prev_timestep = timestep + self.config.num_train_timesteps // self.num_inference_steps
+
+        a_t = self.alphas_cumprod[timestep - 1]
+        a_prev = self.alphas_cumprod[prev_timestep - 1] if prev_timestep >= 0 else self.final_alpha_cumprod
+
+        pred_x0 = (x - (1 - a_t) ** 0.5 * e_t) / a_t.sqrt()
+
+        dir_xt = (1.0 - a_prev).sqrt() * e_t
+
+        prev_sample = a_prev.sqrt() * pred_x0 + dir_xt
+
+        if not return_dict:
+            return (prev_sample, pred_x0)
+        return DDIMSchedulerOutput(prev_sample=prev_sample, pred_original_sample=pred_x0)
+
+    def __len__(self):
+        return self.config.num_train_timesteps

src/diffusers/utils/dummy_pt_objects.py

@@ -345,6 +345,21 @@ class ScoreSdeVePipeline(metaclass=DummyObject):
         requires_backends(cls, ["torch"])
 
 
+class DDIMInverseScheduler(metaclass=DummyObject):
+    _backends = ["torch"]
+
+    def __init__(self, *args, **kwargs):
+        requires_backends(self, ["torch"])
+
+    @classmethod
+    def from_config(cls, *args, **kwargs):
+        requires_backends(cls, ["torch"])
+
+    @classmethod
+    def from_pretrained(cls, *args, **kwargs):
+        requires_backends(cls, ["torch"])
+
+
 class DDIMScheduler(metaclass=DummyObject):
     _backends = ["torch"]
 

tests/pipelines/stable_diffusion/test_stable_diffusion_pix2pix_zero.py

@@ -19,10 +19,12 @@ import unittest
 import numpy as np
 import requests
 import torch
+from PIL import Image
 from transformers import CLIPTextConfig, CLIPTextModel, CLIPTokenizer
 
 from diffusers import (
     AutoencoderKL,
+    DDIMInverseScheduler,
     DDIMScheduler,
     DDPMScheduler,
     EulerAncestralDiscreteScheduler,
@@ -30,7 +32,7 @@ from diffusers import (
     StableDiffusionPix2PixZeroPipeline,
     UNet2DConditionModel,
 )
-from diffusers.utils import slow, torch_device
+from diffusers.utils import load_numpy, slow, torch_device
 from diffusers.utils.testing_utils import require_torch_gpu, skip_mps
 
 from ...test_pipelines_common import PipelineTesterMixin
@@ -94,6 +96,9 @@ class StableDiffusionPix2PixZeroPipelineFastTests(PipelineTesterMixin, unittest.
             "tokenizer": tokenizer,
             "safety_checker": None,
             "feature_extractor": None,
+            "inverse_scheduler": None,
+            "caption_generator": None,
+            "caption_processor": None,
         }
         return components
 
@@ -344,3 +349,83 @@ class StableDiffusionPix2PixZeroPipelineSlowTests(unittest.TestCase):
         mem_bytes = torch.cuda.max_memory_allocated()
         # make sure that less than 8.2 GB is allocated
         assert mem_bytes < 8.2 * 10**9
+
+
+@slow
+@require_torch_gpu
+class InversionPipelineSlowTests(unittest.TestCase):
+    def tearDown(self):
+        super().tearDown()
+        gc.collect()
+        torch.cuda.empty_cache()
+
+    def test_stable_diffusion_pix2pix_inversion(self):
+        img_url = "https://github.com/pix2pixzero/pix2pix-zero/raw/main/assets/test_images/cats/cat_6.png"
+        raw_image = Image.open(requests.get(img_url, stream=True).raw).convert("RGB").resize((512, 512))
+
+        pipe = StableDiffusionPix2PixZeroPipeline.from_pretrained(
+            "CompVis/stable-diffusion-v1-4", safety_checker=None, torch_dtype=torch.float16
+        )
+        pipe.inverse_scheduler = DDIMScheduler.from_config(pipe.scheduler.config)
+        pipe.inverse_scheduler = DDIMInverseScheduler.from_config(pipe.scheduler.config)
+
+        caption = "a photography of a cat with flowers"
+        pipe.scheduler = DDIMScheduler.from_config(pipe.scheduler.config)
+        pipe.enable_model_cpu_offload()
+        pipe.set_progress_bar_config(disable=None)
+
+        generator = torch.manual_seed(0)
+        output = pipe.invert(caption, image=raw_image, generator=generator, num_inference_steps=10)
+        inv_latents = output[0]
+
+        image_slice = inv_latents[0, -3:, -3:, -1].flatten()
+
+        assert inv_latents.shape == (1, 4, 64, 64)
+        expected_slice = np.array([0.8877, 0.0587, 0.7700, -1.6035, -0.5962, 0.4827, -0.6265, 1.0498, -0.8599])
+
+        assert np.abs(expected_slice - image_slice.cpu().numpy()).max() < 1e-3
+
+    def test_stable_diffusion_pix2pix_full(self):
+        img_url = "https://github.com/pix2pixzero/pix2pix-zero/raw/main/assets/test_images/cats/cat_6.png"
+        raw_image = Image.open(requests.get(img_url, stream=True).raw).convert("RGB").resize((512, 512))
+
+        # numpy array of https://huggingface.co/datasets/hf-internal-testing/diffusers-images/blob/main/pix2pix/dog.png
+        expected_image = load_numpy(
+            "https://huggingface.co/datasets/hf-internal-testing/diffusers-images/resolve/main/pix2pix/dog.npy"
+        )
+
+        pipe = StableDiffusionPix2PixZeroPipeline.from_pretrained(
+            "CompVis/stable-diffusion-v1-4", safety_checker=None, torch_dtype=torch.float16
+        )
+        pipe.inverse_scheduler = DDIMScheduler.from_config(pipe.scheduler.config)
+        pipe.inverse_scheduler = DDIMInverseScheduler.from_config(pipe.scheduler.config)
+
+        caption = "a photography of a cat with flowers"
+        pipe.scheduler = DDIMScheduler.from_config(pipe.scheduler.config)
+        pipe.enable_model_cpu_offload()
+        pipe.set_progress_bar_config(disable=None)
+
+        generator = torch.manual_seed(0)
+        output = pipe.invert(caption, image=raw_image, generator=generator)
+        inv_latents = output[0]
+
+        source_prompts = 4 * ["a cat sitting on the street", "a cat playing in the field", "a face of a cat"]
+        target_prompts = 4 * ["a dog sitting on the street", "a dog playing in the field", "a face of a dog"]
+
+        source_embeds = pipe.get_embeds(source_prompts)
+        target_embeds = pipe.get_embeds(target_prompts)
+
+        image = pipe(
+            caption,
+            source_embeds=source_embeds,
+            target_embeds=target_embeds,
+            num_inference_steps=50,
+            cross_attention_guidance_amount=0.15,
+            generator=generator,
+            latents=inv_latents,
+            negative_prompt=caption,
+            output_type="np",
+        ).images
+
+        max_diff = np.abs(expected_image - image).max()
+        assert max_diff < 1e-3