app.py

from pathlib import Path

import torch
import gradio as gr
from torch import nn
from PIL import Image
import numpy as np

LABELS = Path('class_names.txt').read_text().splitlines()

model = nn.Sequential(
    nn.Conv2d(1, 32, 3, padding='same'),
    nn.ReLU(),
    nn.MaxPool2d(2),
    nn.Conv2d(32, 64, 3, padding='same'),
    nn.ReLU(),
    nn.MaxPool2d(2),
    nn.Conv2d(64, 128, 3, padding='same'),
    nn.ReLU(),
    nn.MaxPool2d(2),
    nn.Flatten(),
    nn.Linear(1152, 256),
    nn.ReLU(),
    nn.Linear(256, len(LABELS)),
)
state_dict = torch.load('pytorch_model.bin', map_location='cpu')
model.load_state_dict(state_dict, strict=False)
model.eval()

def predict(im_dict):
    im_raw = im_dict['composite'][:,:,3]
    img = Image.fromarray(im_raw)
    img_small = img.resize([24,28],resample=0)
    im = np.array(np.uint8(img_small))
    im = np.transpose(im,(1,0))
    x = torch.tensor(im, dtype=torch.float32).unsqueeze(0).unsqueeze(0) / 255.

    with torch.no_grad():
        out = model(x)

    probabilities = torch.nn.functional.softmax(out[0], dim=0)

    values, indices = torch.topk(probabilities, 5)

    return {LABELS[i]: v.item() for i, v in zip(indices, values)}

interface = gr.Interface(
    predict,
    inputs="sketchpad",
    outputs='label',
    title="Sketch Recognition",
    description="Who wants to play Pictionary? Draw a common object like a shovel or a laptop, and the algorithm will guess in real time!",
    article = "<p style='text-align: center'>Sketch Recognition | Demo Model</p>",
    live=True)
interface.launch(debug=True)