resnet-image-embedding/resnet_image_embedding.py

# Copyright 2021 Zilliz. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import sys
import numpy
import torch
import torchvision

from pathlib import Path
from typing import NamedTuple

from towhee.operator import Operator


class ResnetImageEmbedding(Operator):
    """
    PyTorch model for image embedding.
    """
    def __init__(self, model_name: str, framework: str = 'pytorch') -> None:
        super().__init__()
        sys.path.append(str(Path(__file__).parent))
        if framework == 'pytorch':
            from pytorch.model import Model
        self.model = Model(model_name)

    def __call__(self, img_tensor: torch.Tensor) -> NamedTuple('Outputs', [('feature_vector', numpy.ndarray)]):
        embedding = self.model(img_tensor)
        Outputs = NamedTuple('Outputs', [('feature_vector', numpy.ndarray)])
        return Outputs(embedding)