app.py

import gradio as gr
import numpy as np

def on_submit(img):
    img = img['composite']
    print(img.shape)
    print(img.dtype)
    print(img[:3, :3])
    return f"Sum: {np.sum(img)}"

iface = gr.Interface(
    title = "LeNet",
    fn = on_submit,
    inputs=gr.Sketchpad(image_mode='P'),
    outputs=gr.Label(),
)
iface.launch()