diffusers/pr_14409/en/api/pipelines/nucleusmoe_image.md

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# NucleusMoE-Image

[NucleusMoE-Image](https://huggingface.co/NucleusAI/NucleusMoE-Image) is a text-to-image model that pairs a single-stream DiT with Mixture-of-Experts feed-forward layers, cross-attention to a Qwen3-VL text encoder, and a flow-matching Euler discrete scheduler.

> [!TIP]
> Make sure to check out the Schedulers [guide](../../using-diffusers/schedulers) to learn how to explore the tradeoff between scheduler speed and quality, and see the [reuse components across pipelines](../../using-diffusers/loading#reuse-a-pipeline) section to learn how to efficiently load the same components into multiple pipelines.

## NucleusMoEImagePipeline[[diffusers.NucleusMoEImagePipeline]]

#### diffusers.NucleusMoEImagePipeline[[diffusers.NucleusMoEImagePipeline]]

```python
diffusers.NucleusMoEImagePipeline(transformer: NucleusMoEImageTransformer2DModel, scheduler: FlowMatchEulerDiscreteScheduler, vae: AutoencoderKLQwenImage, text_encoder: Qwen3VLForConditionalGeneration, processor: Qwen3VLProcessor)
```

[Source](https://github.com/huggingface/diffusers/blob/vr_14409/src/diffusers/pipelines/nucleusmoe_image/pipeline_nucleusmoe_image.py#L132)

**Parameters:**

transformer (`NucleusMoEImageTransformer2DModel`) : Conditional Transformer (MMDiT) architecture to denoise the encoded image latents.

scheduler ([FlowMatchEulerDiscreteScheduler](/docs/diffusers/pr_14409/en/api/schedulers/flow_match_euler_discrete#diffusers.FlowMatchEulerDiscreteScheduler)) : A scheduler to be used in combination with `transformer` to denoise the encoded image latents.

vae ([AutoencoderKLQwenImage](/docs/diffusers/pr_14409/en/api/models/autoencoderkl_qwenimage#diffusers.AutoencoderKLQwenImage)) : Variational Auto-Encoder (VAE) Model to encode and decode images to and from latent representations.

text_encoder (`Qwen3VLForConditionalGeneration`) : Text encoder for computing prompt embeddings.

processor (`Qwen3VLProcessor`) : Processor for tokenizing text inputs.

Pipeline for text-to-image generation using NucleusMoE.

This pipeline uses a single-stream DiT with Mixture-of-Experts feed-forward layers, cross-attention to a Qwen3-VL
text encoder, and a flow-matching Euler discrete scheduler.

#### __call__[[diffusers.NucleusMoEImagePipeline.__call__]]

```python
__call__(prompt: str | list[str] = None, negative_prompt: str | list[str] = None, guidance_scale: float = 4.0, height: int | None = None, width: int | None = None, num_inference_steps: int = 50, sigmas: list[float] | None = None, num_images_per_prompt: int = 1, max_sequence_length: int | None = None, return_index: int | None = None, generator: typing.Union[torch.Generator, list[torch.Generator], NoneType] = None, latents: typing.Optional[torch.Tensor] = None, prompt_embeds: typing.Optional[torch.Tensor] = None, prompt_embeds_mask: typing.Optional[torch.Tensor] = None, negative_prompt_embeds: typing.Optional[torch.Tensor] = None, negative_prompt_embeds_mask: typing.Optional[torch.Tensor] = None, output_type: str | None = 'pil', return_dict: bool = True, attention_kwargs: dict[str, typing.Any] | None = None, callback_on_step_end: typing.Optional[typing.Callable[[int, int, dict], NoneType]] = None, callback_on_step_end_tensor_inputs: list = ['latents'])
```

[Source](https://github.com/huggingface/diffusers/blob/vr_14409/src/diffusers/pipelines/nucleusmoe_image/pipeline_nucleusmoe_image.py#L379)

**Parameters:**

prompt (`str` or `list[str]`, *optional*) : The prompt or prompts to guide the image generation. If not defined, one has to pass `prompt_embeds`.

negative_prompt (`str` or `list[str]`, *optional*) : The prompt or prompts not to guide the image generation. If not defined, an empty string is used when `true_cfg_scale > 1`.

guidance_scale (`float`, *optional*, defaults to 4.0) : Classifier-free guidance scale. Values greater than 1 enable CFG.

return_index (`int`, *optional*) : Layer index of the text encoder output to use for the prompt embeddings.

height (`int`, *optional*, defaults to `self.default_sample_size * self.vae_scale_factor`) : The height in pixels of the generated image.

width (`int`, *optional*, defaults to `self.default_sample_size * self.vae_scale_factor`) : The width in pixels of the generated image.

num_inference_steps (`int`, *optional*, defaults to 50) : The number of denoising steps.

sigmas (`list[float]`, *optional*) : Custom sigmas for the denoising schedule. If not defined, a linear schedule is used.

num_images_per_prompt (`int`, *optional*, defaults to 1) : The number of images to generate per prompt.

generator (`torch.Generator` or `list[torch.Generator]`, *optional*) : One or a list of torch generators to make generation deterministic.

latents (`torch.Tensor`, *optional*) : Pre-generated noisy latents to be used as inputs for image generation.

prompt_embeds (`torch.Tensor`, *optional*) : Pre-generated text embeddings.

prompt_embeds_mask (`torch.Tensor`, *optional*) : Attention mask for pre-generated text embeddings.

negative_prompt_embeds (`torch.Tensor`, *optional*) : Pre-generated negative text embeddings.

negative_prompt_embeds_mask (`torch.Tensor`, *optional*) : Attention mask for pre-generated negative text embeddings.

output_type (`str`, *optional*, defaults to `"pil"`) : The output format of the generated image. Choose between `"pil"`, `"np"`, or `"latent"`.

return_dict (`bool`, *optional*, defaults to `True`) : Whether or not to return a `NucleusMoEImagePipelineOutput` instead of a plain tuple.

attention_kwargs (`dict`, *optional*) : Kwargs passed to the attention processor.

callback_on_step_end (`Callable`, *optional*) : A function called at the end of each denoising step.

callback_on_step_end_tensor_inputs (`list`, *optional*) : Tensor inputs for the `callback_on_step_end` function.

max_sequence_length (`int`, defaults to 512) : Maximum sequence length for the text prompt.

**Returns:** `NucleusMoEImagePipelineOutput` or `tuple`

`NucleusMoEImagePipelineOutput` if `return_dict` is True, otherwise a `tuple` where the first element
is a list with the generated images.

Function invoked when calling the pipeline for generation.

Examples:
```py
>>> import torch
>>> from diffusers import NucleusMoEImagePipeline

>>> pipe = NucleusMoEImagePipeline.from_pretrained("NucleusAI/NucleusMoE-Image", torch_dtype=torch.bfloat16)
>>> pipe.to("cuda")
>>> prompt = "A cat holding a sign that says hello world"
>>> image = pipe(prompt, num_inference_steps=50).images[0]
>>> image.save("nucleus_moe.png")
```

#### encode_prompt[[diffusers.NucleusMoEImagePipeline.encode_prompt]]

```python
encode_prompt(prompt: str | list[str] = None, device: typing.Optional[torch.device] = None, num_images_per_prompt: int = 1, prompt_embeds: typing.Optional[torch.Tensor] = None, prompt_embeds_mask: typing.Optional[torch.Tensor] = None, max_sequence_length: int | None = None, return_index: int | None = None)
```

[Source](https://github.com/huggingface/diffusers/blob/vr_14409/src/diffusers/pipelines/nucleusmoe_image/pipeline_nucleusmoe_image.py#L187)

**Parameters:**

prompt (`str` or `list[str]`, *optional*) : The prompt or prompts to encode.

device (`torch.device`, *optional*) : Torch device for the resulting tensors.

num_images_per_prompt (`int`, defaults to 1) : Number of images to generate per prompt.

prompt_embeds (`torch.Tensor`, *optional*) : Pre-generated text embeddings. Skips encoding when provided.

prompt_embeds_mask (`torch.Tensor`, *optional*) : Attention mask for pre-generated embeddings.

max_sequence_length (`int`, defaults to 1024) : Maximum token length for the encoded prompt.

Encode text prompt(s) into embeddings using the Qwen3-VL text encoder.

## NucleusMoEImagePipelineOutput[[diffusers.pipelines.nucleusmoe_image.pipeline_output.NucleusMoEImagePipelineOutput]]

#### diffusers.pipelines.nucleusmoe_image.pipeline_output.NucleusMoEImagePipelineOutput[[diffusers.pipelines.nucleusmoe_image.pipeline_output.NucleusMoEImagePipelineOutput]]

```python
diffusers.pipelines.nucleusmoe_image.pipeline_output.NucleusMoEImagePipelineOutput(images: list[PIL.Image.Image] | numpy.ndarray)
```

[Source](https://github.com/huggingface/diffusers/blob/vr_14409/src/diffusers/pipelines/nucleusmoe_image/pipeline_output.py#L10)

**Parameters:**

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.

Output class for NucleusMoE Image pipelines.