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*This model was published in HF papers on 2023-04-14 and contributed to Hugging Face Transformers on 2023-07-18.*

<div style="float: right;">
    <div class="flex flex-wrap space-x-1">
        <img alt="FlashAttention" src="https://img.shields.io/badge/%E2%9A%A1%EF%B8%8E%20FlashAttention-eae0c8?style=flat">
        <img alt="SDPA" src="https://img.shields.io/badge/SDPA-DE3412?style=flat&logo=pytorch&logoColor=white">
    </div>
</div>

# DINOv2

[DINOv2](https://huggingface.co/papers/2304.07193) is a vision foundation model that uses [ViT](./vit) as a feature extractor for multiple downstream tasks like image classification and depth estimation. It focuses on stabilizing and accelerating training through techniques like a faster memory-efficient attention, sequence packing, improved stochastic depth, Fully Sharded Data Parallel (FSDP), and model distillation.

You can find all the original DINOv2 checkpoints under the [Dinov2](https://huggingface.co/collections/facebook/dinov2-6526c98554b3d2576e071ce3) collection.

> [!TIP]
> Click on the DINOv2 models in the right sidebar for more examples of how to apply DINOv2 to different vision tasks.

The example below demonstrates how to obtain an image embedding with [`Pipeline`] or the [`AutoModel`] class.

<hfoptions id="usage">
<hfoption id="Pipeline">

```python
from transformers import pipeline


pipe = pipeline(
    task="image-classification",
    model="facebook/dinov2-small-imagenet1k-1-layer",
    device=0
)

pipe("https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/pipeline-cat-chonk.jpeg")
```

</hfoption>
<hfoption id="AutoModel">

```python
import requests
from PIL import Image

from transformers import AutoImageProcessor, AutoModelForImageClassification


url = "http://images.cocodataset.org/val2017/000000039769.jpg"
image = Image.open(requests.get(url, stream=True).raw)

processor = AutoImageProcessor.from_pretrained("facebook/dinov2-small-imagenet1k-1-layer")
model = AutoModelForImageClassification.from_pretrained(
    "facebook/dinov2-small-imagenet1k-1-layer",
    device_map="auto",
    attn_implementation="sdpa"
)

inputs = processor(images=image, return_tensors="pt").to(model.device)
logits = model(**inputs).logits
predicted_class_idx = logits.argmax(-1).item()
print("Predicted class:", model.config.id2label[predicted_class_idx])
```

</hfoption>
</hfoptions>

Quantization reduces the memory burden of large models by representing the weights in a lower precision. Refer to the [Quantization](../quantization/overview) overview for more available quantization backends.

The example below uses [torchao](../quantization/torchao) to only quantize the weights to int4.

```python
# pip install torchao
import requests
from PIL import Image
from torchao.quantization import Int4WeightOnlyConfig

from transformers import AutoImageProcessor, AutoModelForImageClassification, TorchAoConfig


url = 'http://images.cocodataset.org/val2017/000000039769.jpg'
image = Image.open(requests.get(url, stream=True).raw)

processor = AutoImageProcessor.from_pretrained('facebook/dinov2-giant-imagenet1k-1-layer')

quant_config = Int4WeightOnlyConfig(group_size=128)
quantization_config = TorchAoConfig(quant_type=quant_config)

model = AutoModelForImageClassification.from_pretrained(
    'facebook/dinov2-giant-imagenet1k-1-layer',
    device_map="auto",
    quantization_config=quantization_config
)

inputs = processor(images=image, return_tensors="pt").to(model.device)
outputs = model(**inputs)
logits = outputs.logits
predicted_class_idx = logits.argmax(-1).item()
print("Predicted class:", model.config.id2label[predicted_class_idx])
```

## Notes

- The example below shows how to split the output tensor into:
  - one embedding for the whole image, commonly referred to as a `CLS` token,
    useful for classification and retrieval
  - a set of local embeddings, one for each `14x14` patch of the input image,
    useful for dense tasks, such as semantic segmentation

  ```py
  from transformers import AutoImageProcessor, AutoModel
  from PIL import Image
  import requests

  url = 'http://images.cocodataset.org/val2017/000000039769.jpg'
  image = Image.open(requests.get(url, stream=True).raw)
  print(image.height, image.width)  # [480, 640]

  processor = AutoImageProcessor.from_pretrained('facebook/dinov2-base')
  model = AutoModel.from_pretrained('facebook/dinov2-base', device_map="auto")
  patch_size = model.config.patch_size

  inputs = processor(images=image, return_tensors="pt").to(model.device)
  print(inputs.pixel_values.shape)  # [1, 3, 224, 224]
  batch_size, rgb, img_height, img_width = inputs.pixel_values.shape
  num_patches_height, num_patches_width = img_height // patch_size, img_width // patch_size
  num_patches_flat = num_patches_height * num_patches_width

  outputs = model(**inputs)
  last_hidden_states = outputs[0]
  print(last_hidden_states.shape)  # [1, 1 + 256, 768]
  assert last_hidden_states.shape == (batch_size, 1 + num_patches_flat, model.config.hidden_size)

  cls_token = last_hidden_states[:, 0, :]
  patch_features = last_hidden_states[:, 1:, :].unflatten(1, (num_patches_height, num_patches_width))
  ```

- Use [torch.jit.trace](https://pytorch.org/docs/stable/generated/torch.jit.trace.html) to speedup inference.
  However, it will produce some mismatched elements. The difference between the original and traced model is 1e-4.

  ```py
  import torch
  from transformers import AutoImageProcessor, AutoModel
  from PIL import Image
  import requests

  url = 'http://images.cocodataset.org/val2017/000000039769.jpg'
  image = Image.open(requests.get(url, stream=True).raw)

  processor = AutoImageProcessor.from_pretrained('facebook/dinov2-base')
  model = AutoModel.from_pretrained('facebook/dinov2-base', device_map="auto")

  inputs = processor(images=image, return_tensors="pt").to(model.device)
  outputs = model(**inputs)
  last_hidden_states = outputs[0]

  # We have to force return_dict=False for tracing
  model.config.return_dict = False

  with torch.no_grad():
      traced_model = torch.jit.trace(model, [inputs.pixel_values])
      traced_outputs = traced_model(inputs.pixel_values)

  print((last_hidden_states - traced_outputs[0]).abs().max())
  ```

## Dinov2Config

[[autodoc]] Dinov2Config

## Dinov2Model

[[autodoc]] Dinov2Model
    - forward

## Dinov2ForImageClassification

[[autodoc]] Dinov2ForImageClassification
    - forward
