---
library_name: diffusers
tags:
- modular-diffusers
- diffusers
- cosmos3-omni
- text-to-image
---
This is a modular diffusion pipeline built with 🧨 Diffusers' modular pipeline framework.

**Pipeline Type**: Cosmos3DistilledBlocks

**Description**: Modular pipeline blocks for distilled (few-step) Cosmos3 generation modes.

This pipeline uses a 4-block architecture that can be customized and extended.

## Example Usage

[TODO]

## Pipeline Architecture

This modular pipeline is composed of the following blocks:

1. **text_encoder** (`Cosmos3DistilledTextEncoderStep`)
   - Prepares distilled prompt token IDs. Classifier-free guidance is baked into the weights, so `negative_prompt` is not exposed and the unconditional branch is derived from an empty prompt.
2. **vae_encoder** (`Cosmos3DistilledAutoVaeEncoderStep`)
   - Auto VAE conditioning block for distilled Cosmos3.
3. **denoise** (`Cosmos3DistilledVisionCoreDenoiseStep`)
   - Runs the text-and-vision distilled Cosmos3 denoising workflow.
4. **decode** (`Cosmos3VideoDecodeStep`)
   - Decodes denoised vision latents into video outputs. 

## Model Components

1. text_tokenizer (`AutoTokenizer`)
2. vae (`AutoencoderKLWan`)
3. video_processor (`VideoProcessor`)
4. transformer (`Cosmos3OmniTransformer`)
5. scheduler (`FlowMatchEulerDiscreteScheduler`) 

## Configuration Parameters

is_distilled (default: True)
    distilled_sigmas (default: None)

## Workflow Input Specification

<details>
<summary><strong>text2image</strong></summary>

- `prompt` (`str`): The text prompt that guides Cosmos3 generation.
- `num_frames` (`int`, *optional*): Number of frames to generate.

</details>

<details>
<summary><strong>text2video</strong></summary>

- `prompt` (`str`): The text prompt that guides Cosmos3 generation.

</details>

<details>
<summary><strong>image2video</strong></summary>

- `prompt` (`str`): The text prompt that guides Cosmos3 generation.
- `image` (`None`, *optional*): Reference image for image-to-video conditioning.

</details>

<details>
<summary><strong>video2video</strong></summary>

- `prompt` (`str`): The text prompt that guides Cosmos3 generation.
- `video` (`None`, *optional*): Reference video for video-to-video conditioning.

</details>


## Input/Output Specification

**Inputs:**

- `prompt` (`str`): The text prompt that guides Cosmos3 generation.
- `num_frames` (`int`, *optional*): Number of frames to generate.
- `height` (`int`, *optional*): Height of the generated video or image in pixels.
- `width` (`int`, *optional*): Width of the generated video or image in pixels.
- `fps` (`float`, *optional*, defaults to `24.0`): Frame rate of the generated video.
- `use_system_prompt` (`bool`, *optional*, defaults to `True`): Whether to prepend the Cosmos3 system prompt.
- `add_resolution_template` (`bool`, *optional*, defaults to `True`): Whether to add resolution metadata to the prompt.
- `add_duration_template` (`bool`, *optional*, defaults to `True`): Whether to add duration metadata to the prompt.
- `video` (`None`, *optional*): Reference video for video-to-video conditioning.
- `condition_frame_indexes_vision` (`tuple | list`, *optional*, defaults to `(0, 1)`): Latent-frame indexes to preserve from the conditioning video.
- `condition_video_keep` (`str`, *optional*, defaults to `first`): Which end of a longer conditioning video to use: `first` or `last`.
- `image` (`None`, *optional*): Reference image for image-to-video conditioning.
- `x0_tokens_vision` (`Tensor`, *optional*): Vision latents encoded from the conditioning image or video.
- `vision_condition_frames` (`list`, *optional*): Latent-frame indexes fixed by visual conditioning.
- `latents` (`Tensor`, *optional*): Pre-generated noisy vision latents.
- `generator` (`Generator`, *optional*): Torch generator for deterministic generation.
- `num_inference_steps` (`int`, *optional*): The number of denoising steps.
- `guidance_scale` (`float`, *optional*): Unused for distilled checkpoints; classifier-free guidance is baked into the weights and the scale is forced to 1.0. Passing a value other than 1.0 raises an error.
- `**denoiser_input_fields` (`None`, *optional*): conditional model inputs for the denoiser: e.g. prompt_embeds, negative_prompt_embeds, etc.
- `output_type` (`str`, *optional*, defaults to `pil`): Output format: 'pil', 'np', 'pt'.

**Outputs:**

- `videos` (`list`): The generated videos.