app.py

import gradio as gr
import torch
import torchvision.transforms as transforms
from PIL import Image
import json
import os
# from leaf_disease_predict import ResNet9, load_model, predict_image, CLASS_NAMES

class ImageClassificationBase(torch.nn.Module):
    def validation_step(self, batch):
        images, labels = batch
        out = self(images)
        loss = torch.nn.functional.cross_entropy(out, labels)
        acc = accuracy(out, labels)
        return {"val_loss": loss.detach(), "val_accuracy": acc}
    
    def validation_epoch_end(self, outputs):
        batch_losses = [x["val_loss"] for x in outputs]
        batch_accuracy = [x["val_accuracy"] for x in outputs]
        epoch_loss = torch.stack(batch_losses).mean()
        epoch_accuracy = torch.stack(batch_accuracy).mean()
        return {"val_loss": epoch_loss, "val_accuracy": epoch_accuracy}
    
    def epoch_end(self, epoch, result):
        print("Epoch [{}], last_lr: {:.5f}, train_loss: {:.4f}, val_loss: {:.4f}, val_acc: {:.4f}".format(
            epoch, result['lrs'][-1], result['train_loss'], result['val_loss'], result['val_accuracy']))

def ConvBlock(in_channels, out_channels, pool=False):
    layers = [torch.nn.Conv2d(in_channels, out_channels, kernel_size=3, padding=1),
             torch.nn.BatchNorm2d(out_channels),
             torch.nn.ReLU(inplace=True)]
    if pool:
        layers.append(torch.nn.MaxPool2d(4))
    return torch.nn.Sequential(*layers)

class ResNet9(ImageClassificationBase):
    def __init__(self, in_channels, num_diseases):
        super().__init__()
        
        self.conv1 = ConvBlock(in_channels, 64)
        self.conv2 = ConvBlock(64, 128, pool=True)
        self.res1 = torch.nn.Sequential(ConvBlock(128, 128), ConvBlock(128, 128))
        
        self.conv3 = ConvBlock(128, 256, pool=True)
        self.conv4 = ConvBlock(256, 512, pool=True)
        self.res2 = torch.nn.Sequential(ConvBlock(512, 512), ConvBlock(512, 512))
        
        self.classifier = torch.nn.Sequential(torch.nn.MaxPool2d(4),
                                       torch.nn.Flatten(),
                                       torch.nn.Linear(512, num_diseases))
        
    def forward(self, xb):
        out = self.conv1(xb)
        out = self.conv2(out)
        out = self.res1(out) + out
        out = self.conv3(out)
        out = self.conv4(out)
        out = self.res2(out) + out
        out = self.classifier(out)
        return out

CLASS_NAMES = [
    'Apple___Apple_scab', 'Apple___Black_rot', 'Apple___Cedar_apple_rust', 'Apple___healthy',
    'Blueberry___healthy', 'Cherry_(including_sour)___Powdery_mildew', 'Cherry_(including_sour)___healthy',
    
]

def predict_image(image_path, model):
    transform = transforms.Compose([
        transforms.Resize((256, 256)),
        transforms.ToTensor(),
    ])
    
    img = Image.open(image_path).convert('RGB')
    img_tensor = transform(img).unsqueeze(0)
    
    with torch.no_grad():
        outputs = model(img_tensor)
        _, predicted = torch.max(outputs, 1)
        
    return CLASS_NAMES[predicted.item()]


def load_model(model_path):
    model = torch.load(model_path, map_location=torch.device('cpu'))
    model.eval()
    return model



# Load the model
model_path = 'models/leaf_disease_res50_model_epoch_10.pth'
model = load_model(model_path)
model.eval()

# Define the prediction function
def predict(image):
    # Convert Gradio image input to PIL image
    image = Image.fromarray(image.astype('uint8'), 'RGB')
    
    # Save the uploaded file temporarily
    temp_image_path = "temp_image.jpg"
    image.save(temp_image_path)
    
    # Make prediction
    prediction = predict_image(temp_image_path, model)
    
    # Remove temporary file
    os.remove(temp_image_path)
    
    # Get confidence scores
    transform = transforms.Compose([
        transforms.Resize((256, 256)),
        transforms.ToTensor(),
    ])
    img_tensor = transform(image).unsqueeze(0)
    with torch.no_grad():
        outputs = model(img_tensor)
        probabilities = torch.nn.functional.softmax(outputs[0], dim=0)
    
    # Get top 5 predictions
    top5_prob, top5_catid = torch.topk(probabilities, 5)
    top_predictions = {CLASS_NAMES[top5_catid[i]]: top5_prob[i].item()*100 for i in range(top5_prob.size(0))}
    
    # Create a JSON response
    response = {
        "prediction": prediction,
        "confidence_scores": top_predictions
    }
    
    # For the image output, we'll just return the original image for now
    # You can modify this part to add a bounding box if your model provides localization
    return json.dumps(response), image

# Define Gradio interface
iface = gr.Interface(
    fn=predict,
    inputs=gr.Image(),
    outputs=[gr.JSON(label="Prediction Result"), gr.Image(label="Processed Image")],
    title="Plant Disease Predictor",
    description="Upload an image of a plant leaf to predict if it has a disease."
)

# Launch the app
iface.launch()