File size: 6,467 Bytes

---
license: mit
pipeline_tag: image-text-to-image
library_name: diffusers
tags:
  - comfyui
  - text-to-image
  - image-editing
  - fp8
  - quantized
  - distilled
---

# HiDream-O1-Image-Dev — FP8 Mixed (ComfyUI)

This is the **FP8 mixed-precision** quantization of [HiDream-ai/HiDream-O1-Image-Dev](https://huggingface.co/HiDream-ai/HiDream-O1-Image-Dev) — the **distilled** variant of HiDream-O1-Image — for use with **ComfyUI**. This is the most accessible variant: only **~10 GB VRAM** and just **28 steps**, making it the fastest way to run HiDream O1 locally.


![image](https://cdn-uploads.huggingface.co/production/uploads/63473b59e5c0717e6737b872/_bxsS_0OqBzdcISM6cxYT.png)

> **Custom ComfyUI Node:** [Saganaki22/HiDream_O1-ComfyUI](https://github.com/Saganaki22/HiDream_O1-ComfyUI)


![Screenshot 2026-05-10 005045](https://cdn-uploads.huggingface.co/production/uploads/63473b59e5c0717e6737b872/_UIGcH3PvM4TpKhnuRiNw.png)

---

## Dev vs Full — Key Differences

| | Full Model | Dev Model (this repo) |
| :--- | :---: | :---: |
| Inference Steps | 50 | **28** |
| Guidance Scale (CFG) | 5.0 | **0.0 (disabled)** |
| Shift | 3.0 | 1.0 |
| Scheduler | FlowUniPCMultistepScheduler | FlashFlowMatchEulerDiscreteScheduler |
| Speed | Slower, more detail | **~2× faster** |

The Dev model uses a custom Euler scheduler with built-in noise scaling tuned for fewer steps. CFG is disabled — negative prompts have no effect in Dev mode.

---

## VRAM Requirements

| Precision | Approximate VRAM |
| :--- | :---: |
| BF16 | 17 – 20 GB |
| FP16 | 17 – 20 GB |
| FP8 Mixed (this repo) | **~10 GB** |

This is the recommended variant for GPUs with less than 16 GB VRAM. Combined with the Dev model's 28-step schedule, it is the **lowest-cost way to run HiDream O1** — roughly 2× faster and half the VRAM of the full BF16 model.

> **What is FP8 Mixed?** Weights are stored in `float8_e4m3fn`. Sensitive layers (norms, embeddings, output heads) retain higher precision for stability. On RTX 40xx / H100 (Hopper/Ada), FP8 compute is hardware-accelerated. On older GPUs, weights dequantize on-the-fly — still saving VRAM, with a small speed penalty. Do not set `config.json` dtype to `float8_e4m3fn`; keep it as `bfloat16` — the node detects FP8 from the safetensors tensors directly.

---

## Quick Start — ComfyUI

### 1. Install the Custom Node

```bash
cd ComfyUI/custom_nodes
git clone https://github.com/Saganaki22/HiDream_O1-ComfyUI.git
cd HiDream_O1-ComfyUI
python -m pip install -r requirements.txt
```

Or search for `HiDream O1` in **ComfyUI Manager**.

Suggested transformers version: **4.57.1 – 5.3** (newer versions may break compatibility).

### 2. Download the Weights

Download the **entire model folder** (all files, not just the safetensors) and place it in `ComfyUI/models/diffusion_models/`:

```bash
huggingface-cli download drbaph/HiDream-O1-Image-Dev-FP8 \
    --local-dir ComfyUI/models/diffusion_models/HiDream-O1-Image-Dev-fp8
```

The folder must contain the full Hugging Face support files alongside the weights:
`config.json`, `chat_template.json`, `generation_config.json`, `preprocessor_config.json`, `tokenizer.json`, `tokenizer_config.json`, `vocab.json`, `merges.txt`, `model.safetensors`

### 3. Load in ComfyUI

Use the workflow provided in the custom node repository. The loader will detect `dev` in the folder name and automatically apply Dev settings (28 steps, no CFG, Euler scheduler). Point the model loader to `HiDream-O1-Image-Dev-fp8`.

For the fastest inference on supported hardware, set precision to `fp8_e4m3fn_fast` in the model loader node.

---

## About HiDream-O1-Image

HiDream-O1-Image is a natively unified image generative foundation model built on a **Pixel-level Unified Transformer (UiT)** — no external VAEs, no disjoint text encoders. It encodes raw pixels, text, and task-specific conditions in a single shared token space, supporting:

- **Text-to-image generation** up to 2,048 × 2,048
- **Instruction-based image editing**
- **Subject-driven personalization** (multi-reference IP)
- **Long-text and multilingual text rendering**

At only 9B parameters it matches or exceeds much larger open-source DiTs and leading closed-source models. It debuted at **#8 in the Artificial Analysis Text to Image Arena** (2026-05-05).

---

## Key Features

- 🧬 **Pixel-Level Unified Transformer** — end-to-end on raw pixels, no VAE, no disjoint text encoder
- 🎨 **One Model, Many Tasks** — T2I, editing, personalization, storyboard generation
- ⚡ **28-Step Distilled Dev** — ~2× faster than the full model with minimal quality trade-off
- 💾 **FP8 Quantized** — ~half the VRAM of full-precision variants
- 🖼️ **Native High Resolution** — direct synthesis up to 2,048 × 2,048

---

## All Model Variants

### Full Model
| Repo | Precision | VRAM | Steps |
| :--- | :---: | :---: | :---: |
| [drbaph/HiDream-O1-Image-BF16](https://huggingface.co/drbaph/HiDream-O1-Image-BF16) | BF16 | 17–20 GB | 50 |
| [drbaph/HiDream-O1-Image-FP16](https://huggingface.co/drbaph/HiDream-O1-Image-FP16) | FP16 | 17–20 GB | 50 |
| [drbaph/HiDream-O1-Image-FP8](https://huggingface.co/drbaph/HiDream-O1-Image-FP8) | FP8 Mixed | ~10 GB | 50 |

### Dev Model (distilled, faster)
| Repo | Precision | VRAM | Steps |
| :--- | :---: | :---: | :---: |
| [drbaph/HiDream-O1-Image-Dev-BF16](https://huggingface.co/drbaph/HiDream-O1-Image-Dev-BF16) | BF16 | 17–20 GB | **28** |
| [drbaph/HiDream-O1-Image-Dev-FP16](https://huggingface.co/drbaph/HiDream-O1-Image-Dev-FP16) | FP16 | 17–20 GB | **28** |
| [drbaph/HiDream-O1-Image-Dev-FP8](https://huggingface.co/drbaph/HiDream-O1-Image-Dev-FP8) *(this repo)* | FP8 Mixed | ~10 GB | **28** |

---

## License

The original HiDream-O1-Image model and code are released under the **MIT License**. This FP8 quantization inherits the same license.

---

## Links

- 🔗 Original Dev model: [HiDream-ai/HiDream-O1-Image-Dev](https://huggingface.co/HiDream-ai/HiDream-O1-Image-Dev)
- 🔗 Original Full model: [HiDream-ai/HiDream-O1-Image](https://huggingface.co/HiDream-ai/HiDream-O1-Image)
- 🔧 ComfyUI node: [Saganaki22/HiDream_O1-ComfyUI](https://github.com/Saganaki22/HiDream_O1-ComfyUI)
- 📑 Technical report: [HiDream-O1-Image.pdf](https://github.com/HiDream-ai/HiDream-O1-Image/blob/main/assets/HiDream-O1-Image.pdf)
- 🤗 Online demo: [HiDream-O1-Image-Dev Space](https://huggingface.co/spaces/HiDream-ai/HiDream-O1-Image-Dev)