Overview
OpenAI CLIP (Contrastive Language-Image Pre-training) learns joint text-image representations. Enables zero-shot image classification, image-text similarity, cross-modal search, and image captioning without task-specific training.
Installation
uv pip install openai-clip
Zero-Shot Classification
import clip
import torch
model, preprocess = clip.load("ViT-B/32")
image = preprocess(load_image("photo.jpg")).unsqueeze(0)
text = clip.tokenize(["a dog", "a cat", "a bird"])
with torch.no_grad():
logits, _ = model(image, text)
probs = logits.softmax(dim=-1)
print(f"Predicted: class {probs.argmax().item()} with {probs.max():.2%} confidence")
Text-Image Similarity
images = torch.stack([preprocess(img) for img in [load_image("a.jpg"), load_image("b.jpg")]])
texts = clip.tokenize(["sunset", "ocean", "mountain"])
with torch.no_grad():
similarity = model(images, texts)[0].softmax(dim=-1)