app.py

import copy
import os
import sys
sys.path.append('src')
from collections import defaultdict
from functools import lru_cache

import gradio as gr
import matplotlib.pyplot as plt
import numpy as np
import pandas as pd
import torch
from deep_translator import GoogleTranslator
from Nets import CustomResNet18
from PIL import Image
from torchcam.methods import GradCAM, GradCAMpp, SmoothGradCAMpp, XGradCAM
from torchcam.utils import overlay_mask
from torchvision.transforms.functional import to_pil_image
from tqdm import tqdm
from util import transform

IMAGE_PATH = os.path.join(os.getcwd(), 'src/examples')
RANDOM_IMAGES_TO_SHOW = 10
IMAGES_PER_ROW = 5

CAM_METHODS = {
    "GradCAM": GradCAM,
    "GradCAM++": GradCAMpp,
    "XGradCAM": XGradCAM,
    "SmoothGradCAM++": SmoothGradCAMpp,
}

model = CustomResNet18(90).eval()
model.load_state_dict(torch.load('src/results/models/best_model.pth', map_location=torch.device('cpu')))
cam_model = copy.deepcopy(model)
data_df = pd.read_csv('src/cache/val_df.csv')

def load_random_images():
    random_images = list()
    for i in range(RANDOM_IMAGES_TO_SHOW):
        idx = np.random.randint(0, len(data_df))
        p = os.path.join(IMAGE_PATH, data_df.iloc[idx]['path'])
        p = p.replace('\\', '/')
        p = p.replace('//', '/')
        animal = data_df.iloc[idx]['target']
        if os.path.exists(p):
            random_images.append((animal, Image.open(p)))
    return random_images

def get_class_name(idx):
    return data_df[data_df['encoded_target'] == idx]['target'].values[0]

@lru_cache(maxsize=100)
def get_translated(to_translate):
    return GoogleTranslator(source="en", target="de").translate(to_translate)
for idx in range(90): get_translated(get_class_name(idx))

def infer_image(image):
    image = transform(image)
    image = image.unsqueeze(0)
    with torch.no_grad():
        output = model(image)
    distribution = torch.nn.functional.softmax(output, dim=1)
    ret = defaultdict(float)
    for idx, prob in enumerate(distribution[0]):
        animal = f'{get_class_name(idx)} ({get_translated(get_class_name(idx))})'
        ret[animal] = prob.item()
    return ret

def gradcam(image, alpha, cam_method, layer):
    if layer == 'layer1': layers = [model.resnet.layer1]
    elif layer == 'layer2': layers = [model.resnet.layer2]
    elif layer == 'layer3': layers = [model.resnet.layer3]
    elif layer == 'layer4': layers = [model.resnet.layer4]
    else: layers = [model.resnet.layer1, model.resnet.layer2, model.resnet.layer3, model.resnet.layer4]
    
    model.eval()
    img_tensor = transform(image).unsqueeze(0)
    cam = CAM_METHODS[cam_method](model, target_layer=layers)
    output = model(img_tensor)
    activation_map = cam(output.squeeze(0).argmax().item(), output)
    result = overlay_mask(image, to_pil_image(activation_map[0].squeeze(0), mode='F'), alpha=alpha)
    cam.remove_hooks()
    
    # height maximal 300px
    if result.size[1] > 300:
        ratio = 300 / result.size[1]
        result = result.resize((int(result.size[0] * ratio), 300))
    return result

with gr.Blocks() as demo:
    with open('src/header.md', 'r') as f:
        markdown_string = f.read()
    header = gr.Markdown(markdown_string)
    
    with gr.Row(variant="panel", equal_height=True):
        user_image = gr.Image(
            type="pil",
            label="Upload Your Own Image",
            info="You can also upload your own image for prediction.",
            scale=1,
        )
        
    with gr.Tab("Predict"):
        with gr.Column():
            output = gr.Label(
                num_top_classes=3,
                label="Output",
                info="Top three predicted classes and their confidences.",
                scale=5,
            )
            predict_mode_button = gr.Button(value="Predict Animal", label="Predict", info="Click to make a prediction.", scale=1)
            predict_mode_button.click(fn=infer_image, inputs=[user_image], outputs=output, queue=True)
    
    with gr.Tab("Explain"):
        with gr.Row():
            with gr.Column():
                cam_method = gr.Radio(
                    list(CAM_METHODS.keys()),
                    label="GradCAM Method",
                    value="GradCAM",
                    interactive=True,
                    scale=2,
                )
                cam_method.description = "Here you can choose the GradCAM method."
                cam_method.description_place = "left"
                
                alpha = gr.Slider(
                    minimum=.1,
                    maximum=.9,
                    value=0.5,
                    interactive=True,
                    step=.1,
                    label="Alpha",
                    scale=1,
                )
                alpha.description = "Here you can choose the alpha value."
                alpha.description_place = "left"
                
                layer = gr.Radio(
                    ["layer1", "layer2", "layer3", "layer4", "all"],
                    label="Layer",
                    value="layer4",
                    interactive=True,
                    scale=2,
                )
                layer.description = "Here you can choose the layer to visualize."
                layer.description_place = "left"
                
            with gr.Column():
                output_cam = gr.Image(
                    type="pil",
                    label="GradCAM",
                    info="GradCAM visualization"
                    
                )
                
                gradcam_mode_button = gr.Button(value="Show GradCAM", label="GradCAM", info="Click to make a prediction.", scale=1)
                gradcam_mode_button.click(fn=gradcam, inputs=[user_image, alpha, cam_method, layer], outputs=output_cam, queue=True)
            
    with gr.Tab("Example Images"):
        with gr.Column():
            placeholder = gr.Markdown("## Example Images")
            showed_images = list()
            loaded_images = load_random_images()
            amount_rows = max(1, (len(loaded_images) // IMAGES_PER_ROW))
            if len(loaded_images) == 0:
                print(f"Could not find any images in {IMAGE_PATH}")
                amount_rows = 0
            for i in range(amount_rows):
                with gr.Row():
                    for j in range(IMAGES_PER_ROW):
                        animal, image = loaded_images[i * IMAGES_PER_ROW + j]
                        showed_images.append(gr.Image(
                            value=image,
                            label=animal,
                            type="pil",
                            interactive=False,
                        ))
            
            
            
if __name__ == "__main__":
    demo.queue()
    demo.launch()