app.py

import numpy as np
import gradio as gr
import tensorflow as tf
import cv2

# App title
title = "Welcome to your first sketch recognition app!"

# App description
head = (
    "<center>"
    "<img src='./mnist-classes.png' width=400>"
    "<p>The model is trained to classify numbers (from 0 to 9). "
    "To test it, draw your number in the space provided.</p>"
    "</center>"
)

# GitHub repository link
ref = "Find the complete code [here](https://github.com/ovh/ai-training-examples/tree/main/apps/gradio/sketch-recognition)."


# Class names (from 0 to 9)
labels = ["zero", "one", "two", "three", "four", "five", "six", "seven", "eight", "nine"]

# Load model (trained on MNIST dataset)
model = tf.keras.models.load_model("./sketch_recognition_numbers_model.h5")

""" # Prediction function for sketch recognition
def predict(data):
    print(data['composite'].shape)
    # Reshape image to 28x28
    img = np.reshape(data['composite'], (1, img_size, img_size, 1))
    # Make prediction
    pred = model.predict(img)
    # Get top class
    top_3_classes = np.argsort(pred[0])[-3:][::-1]
    # Get top 3 probabilities
    top_3_probs = pred[0][top_3_classes]
    # Get class names
    class_names = [labels[i] for i in top_3_classes]
    # Return class names and probabilities
    return {class_names[i]: top_3_probs[i] for i in range(3)} """

def predict(data):
    # Extract the 'image' key from the input dictionary
    img = data['image']
    # Convert to NumPy array
    img = np.array(img)

    # Handle RGBA or RGB images
    if img.shape[-1] == 4:  # RGBA
        img = cv2.cvtColor(img, cv2.COLOR_RGBA2RGB)
    if img.shape[-1] == 3:  # RGB
        img = cv2.cvtColor(img, cv2.COLOR_RGB2GRAY)

    # Resize image to 28x28
    img = cv2.resize(img, (28, 28))

    # Normalize pixel values to [0, 1]
    img = img / 255.0

    # Reshape to match model input
    img = img.reshape(1, 28, 28, 1)

    # Model predictions
    preds = model.predict(img)[0]

    # Return the probability for each class
    return {label: float(pred) for label, pred in zip(labels, preds)}

# Top 3 classes
label = gr.Label(num_top_classes=3)

# Open Gradio interface for sketch recognition
interface = gr.Interface(
    fn=predict,
    inputs=gr.Sketchpad(type='numpy'),
    outputs=label,
    title=title,
    description=head,
    article=ref
)
interface.launch(share=True)