imaginAIry/imaginairy/enhancers/describe_image_clip.py

69 lines
2.0 KiB
Python

from functools import lru_cache
from typing import Sequence
import torch
from PIL import Image
from torch import nn
from imaginairy.vendored import clip
device = "cuda" if torch.cuda.is_available() else "cpu"
@lru_cache
def get_model():
model_name = "ViT-L/14"
model, preprocess = clip.load(model_name, device=device)
return model, preprocess
def find_img_text_similarity(image: Image.Image, phrases: Sequence):
"""Find the likelihood of a list of textual concepts existing in the image."""
model, preprocess = get_model()
image = preprocess(image).unsqueeze(0).to(device)
with torch.no_grad():
image_features = model.encode_image(image)
return find_embed_text_similarity(image_features, phrases)
def find_embed_text_similarity(embed_features, phrases):
model, _ = get_model()
text = clip.tokenize(phrases).to(device)
with torch.no_grad():
text_features = model.encode_text(text)
probs = cosine_distance(text_features, embed_features)
probs = [float(p) for p in probs.squeeze(dim=0)]
phrase_probs = list(zip(phrases, probs))
phrase_probs.sort(key=lambda r: r[1], reverse=True)
return phrase_probs
def rank(image_features, text_features, top_count=100):
similarity = torch.zeros((1, text_features.shape[0])).to(device)
for i in range(image_features.shape[0]):
similarity += (
100.0 * image_features[i].unsqueeze(0) @ text_features.T
).softmax(dim=-1)
similarity /= image_features.shape[0]
top_probs, top_labels = similarity.cpu().topk(top_count, dim=-1)
phrase_scores = [
(top_labels[0][i].numpy(), (top_probs[0][i].numpy() * 100))
for i in range(top_count)
]
phrase_scores = [(p, s) for p, s in phrase_scores if s > 0.0001]
phrase_scores.sort(key=lambda ps: ps[1], reverse=True)
return phrase_scores
def cosine_distance(embeds_a, embeds_b):
embeds_a = nn.functional.normalize(embeds_a)
embeds_b = nn.functional.normalize(embeds_b)
return torch.mm(embeds_a, embeds_b.t())