import os
from typing import List, Union
import requests
from ..file_utils import add_end_docstrings, is_torch_available, is_vision_available, requires_backends
from ..utils import logging
from .base import PIPELINE_INIT_ARGS, Pipeline
if is_vision_available():
from PIL import Image
if is_torch_available():
from ..models.auto.modeling_auto import MODEL_FOR_IMAGE_CLASSIFICATION_MAPPING
logger = logging.get_logger(__name__)
[docs]@add_end_docstrings(PIPELINE_INIT_ARGS)
class ImageClassificationPipeline(Pipeline):
"""
Image classification pipeline using any :obj:`AutoModelForImageClassification`. This pipeline predicts the class of
an image.
This image classification pipeline can currently be loaded from :func:`~transformers.pipeline` using the following
task identifier: :obj:`"image-classification"`.
See the list of available models on `huggingface.co/models
<https://huggingface.co/models?filter=image-classification>`__.
"""
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
if self.framework == "tf":
raise ValueError(f"The {self.__class__} is only available in PyTorch.")
requires_backends(self, "vision")
self.check_model_type(MODEL_FOR_IMAGE_CLASSIFICATION_MAPPING)
@staticmethod
def load_image(image: Union[str, "Image.Image"]):
if isinstance(image, str):
if image.startswith("http://") or image.startswith("https://"):
# We need to actually check for a real protocol, otherwise it's impossible to use a local file
# like http_huggingface_co.png
image = Image.open(requests.get(image, stream=True).raw)
elif os.path.isfile(image):
image = Image.open(image)
else:
raise ValueError(
f"Incorrect path or url, URLs must start with `http://` or `https://`, and {image} is not a valid path"
)
elif isinstance(image, Image.Image):
image = image
else:
raise ValueError(
"Incorrect format used for image. Should be an url linking to an image, a local path, or a PIL image."
)
image = image.convert("RGB")
return image
def _sanitize_parameters(self, top_k=None):
postprocess_params = {}
if top_k is not None:
postprocess_params["top_k"] = top_k
return {}, {}, postprocess_params
[docs] def __call__(self, images: Union[str, List[str], "Image", List["Image"]], **kwargs):
"""
Assign labels to the image(s) passed as inputs.
Args:
images (:obj:`str`, :obj:`List[str]`, :obj:`PIL.Image` or :obj:`List[PIL.Image]`):
The pipeline handles three types of images:
- A string containing a http link pointing to an image
- A string containing a local path to an image
- An image loaded in PIL directly
The pipeline accepts either a single image or a batch of images, which must then be passed as a string.
Images in a batch must all be in the same format: all as http links, all as local paths, or all as PIL
images.
top_k (:obj:`int`, `optional`, defaults to 5):
The number of top labels that will be returned by the pipeline. If the provided number is higher than
the number of labels available in the model configuration, it will default to the number of labels.
Return:
A dictionary or a list of dictionaries containing result. If the input is a single image, will return a
dictionary, if the input is a list of several images, will return a list of dictionaries corresponding to
the images.
The dictionaries contain the following keys:
- **label** (:obj:`str`) -- The label identified by the model.
- **score** (:obj:`int`) -- The score attributed by the model for that label.
"""
return super().__call__(images, **kwargs)
[docs] def preprocess(self, image):
image = self.load_image(image)
model_inputs = self.feature_extractor(images=image, return_tensors="pt")
return model_inputs
def _forward(self, model_inputs):
model_outputs = self.model(**model_inputs)
return model_outputs
[docs] def postprocess(self, model_outputs, top_k=5):
if top_k > self.model.config.num_labels:
top_k = self.model.config.num_labels
probs = model_outputs.logits.softmax(-1)[0]
scores, ids = probs.topk(top_k)
scores = scores.tolist()
ids = ids.tolist()
return [{"score": score, "label": self.model.config.id2label[_id]} for score, _id in zip(scores, ids)]