CompanySite/.agents/performance-optimizer/IMAGE_OPTIMIZATION.md

# Image Optimization Report

**Agent:** performance-optimizer
**Date:** 2026-03-21
**Project:** WorkRoot IT Solutions (workroot.in)

---

## Summary

The project had a solid image optimization foundation already in place. This audit identified and implemented targeted improvements to maximize loading performance and Core Web Vitals scores.

---

## Asset Inventory

| File | Size | Format | Location |
|------|------|--------|----------|
| `favicon.svg` | 410 B | SVG | `/public/` |
| `apple-touch-icon.png` | 495 B | PNG | `/public/` |
| `logo.png` | 1.9 KB | PNG | `/public/` |
| `og-image.jpg` | 3.6 KB | JPEG | `/public/` |
| `images/blog/ai-business.jpg` | ~1 KB | JPEG | `/public/images/blog/` |
| `images/blog/astro-intro.jpg` | ~1 KB | JPEG | `/public/images/blog/` |
| `images/blog/cloud-migration.jpg` | ~1 KB | JPEG | `/public/images/blog/` |

**Total local image size:** ~8.4 KB (already minimal)

**Remote images via Unsplash CDN:** All portfolio thumbnails, gallery images, and team member photos are served from `images.unsplash.com` with optimized query parameters (`auto=format&q=75`).

---

## Pre-Existing Optimizations (Already in Place)

These were already implemented before this audit:

- **Sharp image service** configured in `astro.config.mjs` for WebP conversion
- **`OptimizedImage.astro`** component with srcset, lazy loading, aspect ratio preservation
- **`LazyImage.astro`** component with fade-in animation and reduced-motion support
- **`dns-prefetch` + `preconnect`** for `images.unsplash.com` in `BaseLayout.astro`
- **`loading="lazy"` + `decoding="async"`** on all below-fold images
- **`loading="eager"` + `fetchpriority="high"`** on first portfolio thumbnail (LCP candidate)
- **Explicit `width`/`height` attributes** on all images to prevent CLS
- **Unsplash `auto=format&q=75`** parameters for automatic WebP delivery and compression
- **HTML compression** via `compressHTML: true` in Astro config
- **Inline stylesheets** for small CSS to reduce HTTP requests
- **Hover-based prefetch** strategy for faster page transitions
- **`max-image-preview:large`** robots meta tag for richer search results

---

## Changes Made in This Audit

### 1. `astro.config.mjs` — Remote Image Domain Configuration

**Before:**
```js
domains: [],
remotePatterns: [],
```

**After:**
```js
domains: ['images.unsplash.com'],
remotePatterns: [
  { protocol: 'https', hostname: 'images.unsplash.com' },
],
```

**Impact:** Enables Astro's image optimization pipeline to process Unsplash images when using the `<Image>` component, allowing future use of Astro's built-in image optimization for remote sources.

---

### 2. `src/pages/about.astro` — Hero Image Priority

**Change:** The main "team collaborating" hero image changed from `loading="lazy"` to `loading="eager"` with `fetchpriority="high"`.

**Why:** This image is visible above the fold on the About page and is a strong LCP candidate. Loading it eagerly with high priority ensures faster Largest Contentful Paint.

---

### 3. `src/pages/about.astro` — Team Member Images Priority

**Change:** First team member image now uses `loading="eager"` + `fetchpriority="high"`. All others remain `loading="lazy"` + `fetchpriority="auto"`.

**Why:** The first team card is often in the initial viewport on larger screens. Eager loading the first card while keeping others lazy balances fast initial render with bandwidth efficiency.

---

### 4. `src/pages/portfolio.astro` — All-Projects Grid `fetchpriority`

**Change:** Added `fetchpriority="low"` to the smaller "all projects" grid thumbnails (these are below the featured section).

**Why:** These images are well below the fold. Explicitly marking them as low priority prevents them from competing with above-fold resources during the initial page load critical path.

---

### 5. `src/styles/global.css` — Global Image Base Rules

**Added:**
```css
img {
  height: auto;
  max-width: 100%;
}

img[width][height] {
  aspect-ratio: attr(width) / attr(height);
}
```

**Why:** Ensures all images maintain aspect ratio by default, preventing CLS for any `<img>` tags that might not have explicit CSS. The `aspect-ratio` from attributes is the modern CSS approach to CLS prevention.

---

## Loading Strategy Summary

| Page | Image | Strategy | Reason |
|------|-------|----------|--------|
| `about.astro` | Team hero image | `eager` + `fetchpriority="high"` | LCP candidate |
| `about.astro` | First team member | `eager` + `fetchpriority="high"` | Above fold |
| `about.astro` | Other team members | `lazy` + `fetchpriority="auto"` | Below fold |
| `portfolio.astro` | First featured thumbnail | `eager` + `fetchpriority="high"` | LCP candidate |
| `portfolio.astro` | Other featured thumbnails | `lazy` + `fetchpriority="auto"` | Below fold |
| `portfolio.astro` | All-projects grid | `lazy` + `fetchpriority="low"` | Far below fold |
| `portfolio.astro` | Modal gallery images | `eager` | Loaded on-demand when modal opens |
| `blog/index.astro` | Post thumbnails | `lazy` + `decoding="async"` | All below fold |
| `blog/[slug].astro` | Hero image | `eager` + `fetchpriority="high"` | LCP candidate |

---

## Format & Compression Strategy

| Image Type | Format | Quality | How |
|-----------|--------|---------|-----|
| Local JPG/PNG in `src/` | WebP | 80% | Astro Image component |
| Unsplash remote images | Auto (WebP if supported) | 75% | `auto=format&q=75` query params |
| OG image (`/og-image.jpg`) | JPEG | — | Pre-optimized static file |
| Logo (`/logo.png`) | PNG | — | Pre-optimized static file (1.9 KB) |
| Favicon (`/favicon.svg`) | SVG | — | Vector, inherently scalable |

---

## Core Web Vitals Impact

| Metric | Impact | How |
|--------|--------|-----|
| **LCP** | Improved | `fetchpriority="high"` on LCP candidates, `preconnect` for Unsplash |
| **CLS** | Maintained | Explicit `width`/`height` + `aspect-ratio` CSS prevents layout shift |
| **INP** | No change | Image loading doesn't block JS interaction |
| **FCP** | Maintained | Critical resources already loading correctly |

---

## Recommendations for Future Improvements

1. **Replace placeholder blog images** — The three blog images (`ai-business.jpg`, `astro-intro.jpg`, `cloud-migration.jpg`) are ~1 KB placeholder files. Replace with real, high-quality images (800×500px, JPEG/WebP, ~50-100 KB each) for better visual quality.

2. **Self-host critical images** — Consider self-hosting team member photos for the About page instead of relying on Unsplash CDN. This eliminates third-party CDN dependency and gives full control over caching headers.

3. **Add `<picture>` with AVIF** — For local static images, use `<picture>` elements with AVIF as the primary format and WebP as fallback for maximum compression (AVIF is ~50% smaller than WebP for photographic content).

4. **Implement responsive images for OG image** — The current `og-image.jpg` at 3.6 KB is very small and may appear low-quality when shared on social media. Create a proper 1200×630px OG image (ideally ~50 KB after optimization).

5. **Service Worker image caching** — The existing `sw.js` service worker could be extended to cache Unsplash images with a stale-while-revalidate strategy for offline support and faster repeat visits.