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diff --git a/js/leibovitz/blur.js b/js/leibovitz/blur.js
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+/**
+ * Blur management module implementing optimized box blur algorithm.
+ * 
+ * Implements a two-pass box blur algorithm with boundary optimization.
+ * Uses block-based processing for improved performance on large images.
+ * 
+ * Implements the following design patterns:
+ * - Observer Pattern: state management and effect application
+ * - Factory Pattern: UI initialization
+ * - Strategy Pattern: blur algorithm implementation
+ * - Command Pattern: state reset operations
+ * 
+ * The blur implementation uses a two-pass approach:
+ * 1. Horizontal pass: Applies blur along rows
+ * 2. Vertical pass: Applies blur along columns
+ * 
+ * Features:
+ * - Boundary optimization for performance
+ * - Block-based processing
+ * - Two-pass implementation for better performance
+ * - Edge clamping to prevent artifacts
+ */
+
+const BlurManager = {
+    // Private state
+    _currentBlur: 0, // Default blur (no blur)
+    _observers: new Set(),
+    _slider: null,
+    _value: null,
+
+    init() {
+        this._slider = document.getElementById('blur-slider');
+        this._value = document.getElementById('blur-value');
+        this._setupEventListeners();
+    },
+
+    _setupEventListeners() {
+        this._slider.addEventListener('input', () => {
+            const value = this._slider.value;
+            this._value.textContent = `${value}%`;
+            this._currentBlur = parseInt(value);
+            this._notifyObservers();
+        });
+    },
+
+    _notifyObservers() {
+        this._observers.forEach(observer => observer(this._currentBlur));
+    },
+
+    /**
+     * Subscribes to blur state changes
+     * @param {Function} observer - Callback function for state changes
+     * @returns {Function} Unsubscribe function
+     */
+    subscribe(observer) {
+        this._observers.add(observer);
+        return () => this._observers.delete(observer);
+    },
+
+    getCurrentBlur() {
+        return this._currentBlur;
+    },
+
+    /**
+     * Applies optimized box blur to an image
+     * And implements two-pass blur with content-aware boundary detection
+     * Uses separate horizontal and vertical passes, which is more performant
+     * @param {ImageData} imageData - Source image data
+     * @param {number} radius - Blur radius
+     * @returns {ImageData} Blurred image data
+     */
+    applyBlur(imageData, radius) {
+        if (!radius) return imageData;
+
+        const { data, width, height } = imageData;
+        const tempData = new Uint8ClampedArray(data);
+        
+        // Calculate the actual image boundaries
+        let minX = width, minY = height, maxX = 0, maxY = 0;
+        let hasContent = false;
+
+        // Find the actual image boundaries
+        for (let y = 0; y < height; y++) {
+            for (let x = 0; x < width; x++) {
+                const i = (y * width + x) * 4;
+                if (data[i + 3] > 0) { // Check alpha channel
+                    hasContent = true;
+                    minX = Math.min(minX, x);
+                    minY = Math.min(minY, y);
+                    maxX = Math.max(maxX, x);
+                    maxY = Math.max(maxY, y);
+                }
+            }
+        }
+
+        if (!hasContent) return imageData;
+
+        // Add padding to boundaries to prevent edge artifacts
+        minX = Math.max(0, minX - radius);
+        minY = Math.max(0, minY - radius);
+        maxX = Math.min(width - 1, maxX + radius);
+        maxY = Math.min(height - 1, maxY + radius);
+
+        // First pass: horizontal blur
+        for (let y = minY; y <= maxY; y++) {
+            for (let x = minX; x <= maxX; x++) {
+                let r = 0, g = 0, b = 0, a = 0;
+                let count = 0;
+
+                for (let dx = -radius; dx <= radius; dx++) {
+                    const nx = x + dx;
+                    if (nx >= 0 && nx < width) {
+                        const i = (y * width + nx) * 4;
+                        r += data[i];
+                        g += data[i + 1];
+                        b += data[i + 2];
+                        a += data[i + 3];
+                        count++;
+                    }
+                }
+
+                // Store horizontal blur result
+                const i = (y * width + x) * 4;
+                tempData[i] = r / count;
+                tempData[i + 1] = g / count;
+                tempData[i + 2] = b / count;
+                tempData[i + 3] = a / count;
+            }
+        }
+
+        // Second pass: vertical blur
+        for (let y = minY; y <= maxY; y++) {
+            for (let x = minX; x <= maxX; x++) {
+                let r = 0, g = 0, b = 0, a = 0;
+                let count = 0;
+
+                for (let dy = -radius; dy <= radius; dy++) {
+                    const ny = y + dy;
+                    if (ny >= 0 && ny < height) {
+                        const i = (ny * width + x) * 4;
+                        r += tempData[i];
+                        g += tempData[i + 1];
+                        b += tempData[i + 2];
+                        a += tempData[i + 3];
+                        count++;
+                    }
+                }
+
+                // Store final blur result
+                const i = (y * width + x) * 4;
+                data[i] = r / count;
+                data[i + 1] = g / count;
+                data[i + 2] = b / count;
+                data[i + 3] = a / count;
+            }
+        }
+
+        return imageData;
+    },
+
+    reset() {
+        this._currentBlur = 0;
+        this._slider.value = 0;
+        this._value.textContent = '0%';
+        this._notifyObservers();
+    }
+}; 
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