app.py

import gradio as gr
from fastai.vision.all import *
import json

# Load the category-to-name mapping
with open('cat_to_name.json', 'r') as f:
    cat_to_name = json.load(f)

learn = load_learner('flower_classifier.pkl')
labels = learn.dls.vocab

def predict(img):
    img = PILImage.create(img)
    _,_,probs = learn.predict(img)

    predictions = {labels[i]: float(probs[i]) for i in range(len(labels))}
    predictions_with_names = {
        cat_to_name[str(label)]: prob for label, prob in predictions.items()
    }
    return predictions_with_names

title = "<h1>Flower Classifier</h1>"
description = "<p>An introductory project using fastai for transfer learning using an image classification model, Gradio to demo it on a web app, and HuggingFace Spaces for deployment. I used the ResNet34 architecture on the Oxford Flowers 102 dataset, with a random 80%/20% train/test split, input resizing to 224x224x3, batch data augmentation, a learning rate found by `lr_find()`, only 2 training epochs, and the rest of the hyperparameters as fastai defaults. As someone who's learned neural networks from the bottom up with a strong theoretical foundation, it was fun to see how \"easy\" ML can be for simpler tasks, as the model achieves 91% test accuracy (while a random guess would yield 1% accuracy)!</p><p>Feel free to browse the example images below (10 are from the test set, and 2 are my own out-of-distribution images) or upload your own image of a flower. The model may have overfit to the training distribution, as it doesn't generalize well to images with cluttered backgrounds (see my dahlia photo and my tulip photo) and has 100% certainty of correct guesses for some examples in the test set.</p><p>The Oxford Flowers 102 dataset, created by the University of Oxford’s Visual Geometry Group, consists of 8,189 images spanning 102 flower species, designed to challenge fine-grained image classification models. With varying lighting, backgrounds, and an uneven class distribution, it serves as a benchmark for testing model robustness and optimizing classification accuracy, making it popular for transfer learning experiments with models like VGG16, ResNet, and EfficientNet."
labels_table = """<p>Classes included in training:<p>
 <table>
    <tr>
      <td>alpine sea holly</td>
      <td>anthurium</td>
      <td>artichoke</td>
      <td>azalea</td>
      <td>ball moss</td>
      <td>balloon flower</td>
    </tr>
    <tr>
      <td>barbeton daisy</td>
      <td>bearded iris</td>
      <td>bee balm</td>
      <td>bird of paradise</td>
      <td>bishop of llandaff</td>
      <td>black-eyed susan</td>
    </tr>
    <tr>
      <td>blackberry lily</td>
      <td>blanket flower</td>
      <td>bolero deep blue</td>
      <td>bougainvillea</td>
      <td>bromelia</td>
      <td>buttercup</td>
    </tr>
    <tr>
      <td>californian poppy</td>
      <td>camellia</td>
      <td>canna lily</td>
      <td>canterbury bells</td>
      <td>cape flower</td>
      <td>carnation</td>
    </tr>
    <tr>
      <td>cautleya spicata</td>
      <td>clematis</td>
      <td>columbine</td>
      <td>colt's foot</td>
      <td>common dandelion</td>
      <td>corn poppy</td>
    </tr>
    <tr>
      <td>cyclamen</td>
      <td>daffodil</td>
      <td>desert-rose</td>
      <td>english marigold</td>
      <td>fire lily</td>
      <td>foxglove</td>
    </tr>
    <tr>
      <td>frangipani</td>
      <td>fritillary</td>
      <td>garden phlox</td>
      <td>gaura</td>
      <td>gazania</td>
      <td>geranium</td>
    </tr>
    <tr>
      <td>giant white arum lily</td>
      <td>globe thistle</td>
      <td>globe-flower</td>
      <td>grape hyacinth</td>
      <td>great masterwort</td>
      <td>hard-leaved pocket orchid</td>
    </tr>
    <tr>
      <td>hibiscus</td>
      <td>hippeastrum</td>
      <td>japanese anemone</td>
      <td>king protea</td>
      <td>lenten rose</td>
      <td>lotus</td>
    </tr>
    <tr>
      <td>love in the mist</td>
      <td>magnolia</td>
      <td>mallow</td>
      <td>marigold</td>
      <td>mexican aster</td>
      <td>mexican petunia</td>
    </tr>
    <tr>
      <td>monkshood</td>
      <td>moon orchid</td>
      <td>morning glory</td>
      <td>orange dahlia</td>
      <td>osteospermum</td>
      <td>oxeye daisy</td>
    </tr>
    <tr>
      <td>passion flower</td>
      <td>pelargonium</td>
      <td>peruvian lily</td>
      <td>petunia</td>
      <td>pincushion flower</td>
      <td>pink primrose</td>
    </tr>
    <tr>
      <td>pink-yellow dahlia</td>
      <td>poinsettia</td>
      <td>primula</td>
      <td>prince of wales feathers</td>
      <td>purple coneflower</td>
      <td>red ginger</td>
    </tr>
    <tr>
      <td>rose</td>
      <td>ruby-lipped cattleya</td>
      <td>siam tulip</td>
      <td>silverbush</td>
      <td>snapdragon</td>
      <td>spear thistle</td>
    </tr>
    <tr>
      <td>spring crocus</td>
      <td>stemless gentian</td>
      <td>sunflower</td>
      <td>sweet pea</td>
      <td>sweet william</td>
      <td>sword lily</td>
    </tr>
    <tr>
      <td>thorn apple</td>
      <td>tiger lily</td>
      <td>toad lily</td>
      <td>tree mallow</td>
      <td>tree poppy</td>
      <td>trumpet creeper</td>
    </tr>
    <tr>
      <td>wallflower</td>
      <td>water lily</td>
      <td>watercress</td>
      <td>wild pansy</td>
      <td>windflower</td>
      <td>yellow iris</td>
    </tr>
  </table>
"""
# Make examples a list of all image filenames in the examples folder
examples = ["examples/" + filename for filename in os.listdir("examples")]

with gr.Blocks() as demo:
    gr.HTML(title)
    gr.HTML(description)
    gr.Interface(fn=predict,
                inputs=gr.Image(type="pil"),
                outputs=gr.Label(num_top_classes=3),
                examples=examples)
    gr.HTML(labels_table)

if __name__ == "__main__":
    demo.launch()