app.py

import gradio as gr
import numpy as np
import cv2
from tensorflow.keras.applications import ResNet50
from tensorflow.keras.applications.resnet50 import preprocess_input
from tensorflow.keras.preprocessing import image
from skimage.metrics import structural_similarity as ssim
import os
import tempfile
from PIL import Image

class ImageCharacterClassifier:
    def __init__(self, similarity_threshold=0.5):
        # Initialize ResNet50 model without top classification layer
        self.model = ResNet50(weights='imagenet', include_top=False, pooling='avg')
        self.similarity_threshold = similarity_threshold

    def load_and_preprocess_image(self, image_path, target_size=(224, 224)):
        # Load and preprocess image for ResNet50
        img = image.load_img(image_path, target_size=target_size)
        img_array = image.img_to_array(img)
        img_array = np.expand_dims(img_array, axis=0)
        img_array = preprocess_input(img_array)
        return img_array

    def extract_features(self, image_path):
        # Extract deep features using ResNet50
        preprocessed_img = self.load_and_preprocess_image(image_path)
        features = self.model.predict(preprocessed_img)
        return features

    def calculate_ssim(self, img1_path, img2_path):
        # Calculate SSIM between two images
        img1 = cv2.imread(img1_path)
        img2 = cv2.imread(img2_path)
        
        if img1 is None or img2 is None:
            return 0.0
        
        # Convert to grayscale if images are in color
        if len(img1.shape) == 3:
            img1 = cv2.cvtColor(img1, cv2.COLOR_BGR2GRAY)
        if len(img2.shape) == 3:
            img2 = cv2.cvtColor(img2, cv2.COLOR_BGR2GRAY)
        
        # Resize images to same dimensions
        img2 = cv2.resize(img2, (img1.shape[1], img1.shape[0]))
        
        score = ssim(img1, img2)
        return score

def process_images(reference_image, comparison_images, similarity_threshold):
    try:
        if reference_image is None:
            return "Please upload a reference image.", []
        
        if not comparison_images:
            return "Please upload comparison images.", []
            
        # Create temporary directory for saving uploaded files
        with tempfile.TemporaryDirectory() as temp_dir:
            # Initialize classifier with the threshold
            classifier = ImageCharacterClassifier(similarity_threshold=similarity_threshold)
            
            # Save reference image
            ref_path = os.path.join(temp_dir, "reference.jpg")
            cv2.imwrite(ref_path, cv2.cvtColor(reference_image, cv2.COLOR_RGB2BGR))
            
            results = []
            html_output = """
            <div style='text-align: center; margin-bottom: 20px;'>
                <h2 style='color: #2c3e50;'>Results</h2>
                <p style='color: #7f8c8d;'>Reference image compared with uploaded images</p>
            </div>
            """
            
            # Extract reference features once
            ref_features = classifier.extract_features(ref_path)
            
            # Process each comparison image
            for i, comp_image in enumerate(comparison_images):
                try:
                    # Save comparison image
                    comp_path = os.path.join(temp_dir, f"comparison_{i}.jpg")
                    
                    try:
                        # First attempt: Try using PIL
                        with Image.open(comp_image.name) as img:
                            img = img.convert('RGB')
                            img_array = np.array(img)
                            cv2.imwrite(comp_path, cv2.cvtColor(img_array, cv2.COLOR_RGB2BGR))
                    except Exception as e1:
                        print(f"PIL failed: {str(e1)}")
                        # Second attempt: Try using OpenCV directly
                        img = cv2.imread(comp_image.name)
                        if img is not None:
                            cv2.imwrite(comp_path, img)
                        else:
                            raise ValueError(f"Could not read image: {comp_image.name}")
                    
                    # Calculate SSIM for structural similarity
                    ssim_score = classifier.calculate_ssim(ref_path, comp_path)
                    
                    # Extract features for physical feature comparison
                    comp_features = classifier.extract_features(comp_path)
                    
                    # Calculate feature differences for physical features
                    feature_diff = np.abs(ref_features - comp_features)
                    
                    # Calculate different aspects of similarity
                    avg_feature_diff = np.mean(feature_diff)
                    max_feature_diff = np.max(feature_diff)
                    feature_similarity = np.dot(ref_features.flatten(), 
                                           comp_features.flatten()) / (
                        np.linalg.norm(ref_features) * np.linalg.norm(comp_features))
                    
                    # Stricter similarity criteria
                    is_similar = True  # Start with assumption of similarity
                    reason = "Images are similar"
                    
                    # First check for major physical feature differences (like misplaced eyes)
                    if max_feature_diff > 0.85 or avg_feature_diff > 0.5:
                        is_similar = False
                        reason = "Major physical differences detected (missing or misplaced features)"
                    # Then check for overall structural similarity
                    elif ssim_score < 0.4:  # Lowered SSIM threshold
                        is_similar = False
                        reason = "Overall structure is too different"
                    # Finally check for feature similarity
                    elif feature_similarity < 0.5:
                        is_similar = False
                        reason = "Features don't match well enough"
                    
                    # Debug information
                    print(f"\nDebug for {os.path.basename(comp_image.name)}:")
                    print(f"SSIM Score: {ssim_score:.3f}")
                    print(f"Max Feature Difference: {max_feature_diff:.3f}")
                    print(f"Average Feature Difference: {avg_feature_diff:.3f}")
                    print(f"Feature Similarity: {feature_similarity:.3f}")
                    
                    # Create HTML output with improved styling and reason
                    status_color = "#27ae60" if is_similar else "#c0392b"  # Green or Red
                    status_text = "SIMILAR" if is_similar else "NOT SIMILAR"
                    status_icon = "✓" if is_similar else "✗"
                    
                    html_output += f"""
                    <div style='
                        margin: 15px 0;
                        padding: 15px;
                        border-radius: 8px;
                        background-color: {status_color}1a;
                        border: 2px solid {status_color};
                        display: flex;
                        align-items: center;
                        justify-content: space-between;
                    '>
                        <div style='display: flex; align-items: center;'>
                            <span style='
                                font-size: 24px;
                                margin-right: 10px;
                                color: {status_color};
                            '>{status_icon}</span>
                            <div>
                                <span style='color: #2c3e50; font-weight: bold; display: block;'>
                                    {os.path.basename(comp_image.name)}
                                </span>
                                <span style='color: {status_color}; font-size: 12px;'>
                                    {reason}
                                </span>
                            </div>
                        </div>
                        <div style='
                            color: {status_color};
                            font-weight: bold;
                            font-size: 16px;
                        '>{status_text}</div>
                    </div>
                    """
                    
                    # Read the processed image back for display
                    display_img = cv2.imread(comp_path)
                    if display_img is not None:
                        display_img = cv2.cvtColor(display_img, cv2.COLOR_BGR2RGB)
                        results.append(display_img)
                    
                except Exception as e:
                    print(f"Error processing {comp_image.name}: {str(e)}")
                    html_output += f"""
                    <div style='
                        margin: 15px 0;
                        padding: 15px;
                        border-radius: 8px;
                        background-color: #e74c3c1a;
                        border: 2px solid #e74c3c;
                    '>
                        <h3 style='color: #e74c3c; margin: 0;'>
                            Error processing: {os.path.basename(comp_image.name)}
                        </h3>
                        <p style='color: #e74c3c; margin: 5px 0 0 0;'>{str(e)}</p>
                    </div>
                    """
            
            return html_output, results
            
    except Exception as e:
        print(f"Main error: {str(e)}")
        return f"""
        <div style='
            padding: 15px;
            border-radius: 8px;
            background-color: #e74c3c1a;
            border: 2px solid #e74c3c;
        '>
            <h3 style='color: #e74c3c; margin: 0;'>Error</h3>
            <p style='color: #e74c3c; margin: 5px 0 0 0;'>{str(e)}</p>
        </div>
        """, []

# Update the interface creation
def create_interface():
    with gr.Blocks() as interface:
        gr.Markdown("# Image Similarity Classifier")
        gr.Markdown("Upload a reference image and up to 10 comparison images to check similarity.")
        
        with gr.Row():
            with gr.Column():
                reference_input = gr.Image(
                    label="Reference Image",
                    type="numpy",
                    image_mode="RGB"
                )
                comparison_input = gr.File(
                    label="Comparison Images (Upload up to 10)", 
                    file_count="multiple",
                    file_types=["image"],
                    maximum=10
                )
                threshold_slider = gr.Slider(
                    minimum=0.0,
                    maximum=1.0,
                    value=0.5,
                    step=0.05,
                    label="Similarity Threshold"
                )
                submit_button = gr.Button("Compare Images", variant="primary")
            
            with gr.Column():
                output_html = gr.HTML(label="Results")
                output_gallery = gr.Gallery(
                    label="Processed Images",
                    columns=5,
                    show_label=True,
                    height="auto"
                )
        
        submit_button.click(
            fn=process_images,
            inputs=[reference_input, comparison_input, threshold_slider],
            outputs=[output_html, output_gallery]
        )
    
    return interface

# Launch the app
if __name__ == "__main__":
    interface = create_interface()
    interface.launch(share=True)