app.py

import numpy as np
import onnxruntime as ort
import gradio as gr
from PIL import Image
from torchvision.models import ResNet50_Weights

weights = ResNet50_Weights.DEFAULT
preprocess = weights.transforms() # Necessary input transformations
ort_session = ort.InferenceSession("resnet50.onnx", providers=["CPUExecutionProvider"])

def preprocess_inputs(img: Image):
    img = preprocess(img)
    img_array = np.array(img).astype(np.float32)
    img_array = np.expand_dims(img_array, axis=0)
    return img_array

def predict(img):
    img = preprocess_inputs(img)
    ort_inputs = {ort_session.get_inputs()[0].name: img}
    ort_outputs = ort_session.run(None, ort_inputs)

    #probs = np.exp(ort_outputs) / np.sum(np.exp(ort_outputs))  # softmax

    label_index = np.argmax(ort_outputs[0], axis=1).item()
    predicted_label = weights.meta["categories"][label_index]
    return predicted_label


demo = gr.Interface(predict, gr.Image(type="pil", image_mode="RGB"), gr.Label(),
                    title="ResNet-50 Using onnxruntime",
                    description="Upload any image and see if resnet-50 can classify it! (1000 possible image classes)",
                    article="Part of a tutorial on [how to deploy an ONNX mode to Hugging Face](https://liamgroen.nl/posts/day-6-deploying-model-to-huggingface-spaces-through-onnx/index.html)")
demo.launch()