unconditional_image_generation.md

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# Unconditional image generation

[[open-in-colab]]

Unconditional image generation is a relatively straightforward task. The model only generates images - without any additional context like text or an image - resembling the training data it was trained on.

The [`DiffusionPipeline`] is the easiest way to use a pre-trained diffusion system for inference.

Start by creating an instance of [`DiffusionPipeline`] and specify which pipeline checkpoint you would like to download.
You can use any of the 🧨 Diffusers [checkpoints](https://huggingface.co/models?library=diffusers&sort=downloads) from the Hub (the checkpoint you'll use generates images of butterflies).

<Tip>

💡 Want to train your own unconditional image generation model? Take a look at the training [guide](../training/unconditional_training) to learn how to generate your own images.

</Tip>

In this guide, you'll use [`DiffusionPipeline`] for unconditional image generation with [DDPM](https://arxiv.org/abs/2006.11239):

```python
from diffusers import DiffusionPipeline

generator = DiffusionPipeline.from_pretrained("anton-l/ddpm-butterflies-128", use_safetensors=True)
```

The [`DiffusionPipeline`] downloads and caches all modeling, tokenization, and scheduling components. 
Because the model consists of roughly 1.4 billion parameters, we strongly recommend running it on a GPU.
You can move the generator object to a GPU, just like you would in PyTorch:

```python
generator.to("cuda")
```

Now you can use the `generator` to generate an image:

```python
image = generator().images[0]
image
```

The output is by default wrapped into a [`PIL.Image`](https://pillow.readthedocs.io/en/stable/reference/Image.html?highlight=image#the-image-class) object.

You can save the image by calling:

```python
image.save("generated_image.png")
```

Try out the Spaces below, and feel free to play around with the inference steps parameter to see how it affects the image quality!

<iframe
	src="https://stevhliu-ddpm-butterflies-128.hf.space"
	frameborder="0"
	width="850"
	height="500"
></iframe>