feat(utils): add feature extraction utilities and tests

This commit is contained in:
2026-03-05 20:48:53 +08:00
parent a16b376dd7
commit 5be4709acf
13 changed files with 247 additions and 138 deletions

View File

@@ -1,9 +1,8 @@
import io
from typing import Any, Dict, List, Optional, Union, cast
from typing import Dict, List, Optional, cast
import torch
from database import db_manager
from datasets import load_dataset
from PIL import Image
from PIL.PngImagePlugin import PngImageFile
from torch import nn
@@ -14,6 +13,9 @@ from transformers import (
BitImageProcessorFast,
Dinov2Model,
)
from utils.feature_extractor import extract_batch_features
from datasets import load_dataset
def pil_image_to_bytes(image: Image.Image, format: str = "PNG") -> bytes:
@@ -86,78 +88,26 @@ class FeatureRetrieval:
batch_size: Number of images to process in a batch.
label_map: Optional mapping from label indices to string names.
"""
device = self.model.device
self.model.eval()
# Extract features using the utility function
cls_tokens = extract_batch_features(
self.processor, self.model, images, batch_size=batch_size
)
for i in tqdm(range(0, len(images), batch_size)):
batch_imgs = images[i : i + batch_size]
for i in tqdm(range(len(labels)), desc="Storing to database"):
batch_label = labels[i] if label_map is None else label_map[labels[i]]
inputs = self.processor(batch_imgs, return_tensors="pt")
# 迁移数据到GPU
inputs.to(device)
outputs = self.model(**inputs)
# 后处理
feats = outputs.last_hidden_state # [B, N, D]
cls_tokens = feats[:, 0] # Get CLS token (first token) for all batch items
cls_tokens = cast(torch.Tensor, cls_tokens)
# 迁移输出到CPU
cls_tokens = cls_tokens.cpu()
batch_labels = (
labels[i : i + batch_size]
if label_map is None
else list(
map(lambda x: label_map[cast(int, x)], labels[i : i + batch_size])
)
)
actual_batch_size = len(batch_labels)
# 存库
# Store to database
db_manager.table.add(
[
{
"id": i + j,
"label": batch_labels[j],
"vector": cls_tokens[j].numpy(),
"binary": pil_image_to_bytes(batch_imgs[j]),
"id": i,
"label": batch_label,
"vector": cls_tokens[i].numpy(),
"binary": pil_image_to_bytes(images[i]),
}
for j in range(actual_batch_size)
]
)
@torch.no_grad()
def extract_single_image_feature(
self, image: Union[Image.Image, Any]
) -> List[float]:
"""Extract feature from a single image without storing to database.
Args:
image: A single image (PIL Image or other supported format).
Returns:
pl.Series: The extracted CLS token feature vector as a Polars Series.
"""
device = self.model.device
self.model.eval()
# 预处理图片
inputs = self.processor(images=image, return_tensors="pt")
inputs.to(device, non_blocking=True)
# 提取特征
outputs = self.model(**inputs)
# 获取 CLS token
feats = outputs.last_hidden_state # [1, N, D]
cls_token = feats[:, 0] # [1, D]
cls_token = cast(torch.Tensor, cls_token)
# 返回 CLS List
return cls_token.cpu().squeeze(0).tolist()
if __name__ == "__main__":
train_dataset = load_dataset("uoft-cs/cifar10", split="train")