đ Model Card: OWLv2
The OWLv2 model offers zero - shot text - conditioned object detection capabilities. It uses CLIP as a backbone and can be queried with text to detect objects in an image, which is valuable for research in computer vision.
đ Quick Start
If you want to use the OWLv2 model with the Transformers library, you can refer to the following code example:
import requests
from PIL import Image
import torch
from transformers import Owlv2Processor, Owlv2ForObjectDetection
processor = Owlv2Processor.from_pretrained("google/owlv2-large-patch14")
model = Owlv2ForObjectDetection.from_pretrained("google/owlv2-large-patch14")
url = "http://images.cocodataset.org/val2017/000000039769.jpg"
image = Image.open(requests.get(url, stream=True).raw)
texts = [["a photo of a cat", "a photo of a dog"]]
inputs = processor(text=texts, images=image, return_tensors="pt")
with torch.no_grad():
outputs = model(**inputs)
target_sizes = torch.Tensor([image.size[::-1]])
results = processor.post_process_object_detection(outputs=outputs, target_sizes=target_sizes, threshold=0.1)
i = 0
text = texts[i]
boxes, scores, labels = results[i]["boxes"], results[i]["scores"], results[i]["labels"]
for box, score, label in zip(boxes, scores, labels):
box = [round(i, 2) for i in box.tolist()]
print(f"Detected {text[label]} with confidence {round(score.item(), 3)} at location {box}")
⨠Features
- Zero - shot Detection: The OWLv2 model can perform zero - shot text - conditioned object detection, allowing users to query an image with one or multiple text queries.
- Multi - modal Backbone: It uses CLIP as its multi - modal backbone, combining a ViT - like Transformer for visual features and a causal language model for text features.
- Open - vocabulary Classification: By replacing the fixed classification layer weights with class - name embeddings from the text model, it enables open - vocabulary classification.
đ Documentation
Model Details
The OWLv2 model (short for Open - World Localization) was proposed in Scaling Open - Vocabulary Object Detection by Matthias Minderer, Alexey Gritsenko, Neil Houlsby. Similar to OWL - ViT, it is a zero - shot text - conditioned object detection model.
The model uses CLIP as its multi - modal backbone. It has a ViT - like Transformer to obtain visual features and a causal language model to get text features. To use CLIP for detection, OWL - ViT removes the final token pooling layer of the vision model and attaches a lightweight classification and box head to each transformer output token. Open - vocabulary classification is achieved by replacing the fixed classification layer weights with class - name embeddings from the text model. The authors first train CLIP from scratch and fine - tune it end - to - end with the classification and box heads on standard detection datasets using a bipartite matching loss. One or multiple text queries per image can be used for zero - shot text - conditioned object detection.
Model Date
June 2023
Model Type
Property |
Details |
Model Type |
The model uses a CLIP backbone with a ViT - L/14 Transformer architecture as an image encoder and a masked self - attention Transformer as a text encoder. These encoders are trained to maximize the similarity of (image, text) pairs via a contrastive loss. The CLIP backbone is trained from scratch and fine - tuned together with the box and class prediction heads with an object detection objective. |
Training Data |
The CLIP backbone of the model was trained on publicly available image - caption data through a combination of crawling websites and using pre - existing image datasets such as YFCC100M. A large portion of the data comes from internet crawling. The prediction heads of OWL - ViT, along with the CLIP backbone, are fine - tuned on publicly available object detection datasets such as COCO and OpenImages. |
Documents
Model Use
Intended Use
The model is intended as a research output for research communities. It aims to help researchers better understand and explore zero - shot, text - conditioned object detection. It can also be used for interdisciplinary studies of the potential impact of such models, especially in areas where identifying objects with unavailable labels during training is required.
Primary intended uses
The primary intended users of these models are AI researchers. We mainly envision that the model will be used by researchers to better understand the robustness, generalization, and other capabilities, biases, and constraints of computer vision models.
Data
The CLIP backbone of the model was trained on publicly available image - caption data. This was accomplished by crawling several websites and using commonly - used pre - existing image datasets like YFCC100M. A significant part of the data comes from internet crawling, which means the data is more representative of people and societies most connected to the internet. The prediction heads of OWL - ViT, along with the CLIP backbone, are fine - tuned on publicly available object detection datasets such as COCO and OpenImages.
(to be updated for v2)
BibTeX entry and citation info
@misc{minderer2023scaling,
title={Scaling Open-Vocabulary Object Detection},
author={Matthias Minderer and Alexey Gritsenko and Neil Houlsby},
year={2023},
eprint={2306.09683},
archivePrefix={arXiv},
primaryClass={cs.CV}
}
đ License
The model is released under the Apache - 2.0 license.