agricidaniel/seo-images

Image Optimization Analysis

Checks

Alt Text

• Present on all <img> elements (except decorative: role="presentation")
• Descriptive: describes the image content, not "image.jpg" or "photo"
• Includes relevant keywords where natural, not keyword-stuffed
• Length: 10-125 characters

Good examples:

• "Professional plumber repairing kitchen sink faucet"
• "Red 2024 Toyota Camry sedan front view"
• "Team meeting in modern office conference room"

Bad examples:

• "image.jpg" (filename, not description)
• "plumber plumbing plumber services" (keyword stuffing)
• "Click here" (not descriptive)

File Size

Tiered thresholds by image category:

| Image Category | Target | Warning | Critical | |----------------|--------|---------|----------| | Thumbnails | < 50KB | > 100KB | > 200KB | | Content images | < 100KB | > 200KB | > 500KB | | Hero/banner images | < 200KB | > 300KB | > 700KB |

Recommend compression to target thresholds where possible without quality loss.

Format

| Format | Browser Support | Use Case | |--------|-----------------|----------| | WebP | 97%+ | Default recommendation | | AVIF | 92%+ | Best compression, newer | | JPEG | 100% | Fallback for photos | | PNG | 100% | Graphics with transparency | | SVG | 100% | Icons, logos, illustrations |

Recommend WebP/AVIF over JPEG/PNG. Check for <picture> element with format fallbacks.

Recommended <picture> Element Pattern

Use progressive enhancement with the most efficient format first:

<picture>
  <source srcset="image.avif" type="image/avif">
  <source srcset="image.webp" type="image/webp">
  <img src="image.jpg" alt="Descriptive alt text" width="800" height="600" loading="lazy" decoding="async">
</picture>

The browser will use the first supported format. Current browser support: AVIF 93.8%, WebP 95.3%.

JPEG XL: Emerging Format

In November 2025, Google's Chromium team reversed its 2022 decision and announced it will restore JPEG XL support in Chrome using a Rust-based decoder. The implementation is feature-complete but not yet in Chrome stable. JPEG XL offers lossless JPEG recompression (~20% savings with zero quality loss) and competitive lossy compression. Not yet practical for web deployment, but worth monitoring for future adoption.

Responsive Images

• srcset attribute for multiple sizes
• sizes attribute matching layout breakpoints
• Appropriate resolution for device pixel ratios

<img
  src="image-800.jpg"
  srcset="image-400.jpg 400w, image-800.jpg 800w, image-1200.jpg 1200w"
  sizes="(max-width: 600px) 400px, (max-width: 1200px) 800px, 1200px"
  alt="Description"
>

Lazy Loading

• loading="lazy" on below-fold images
• Do NOT lazy-load above-fold/hero images (hurts LCP)
• Check for native vs JavaScript-based lazy loading

<!-- Below fold - lazy load -->
<img src="photo.jpg" loading="lazy" alt="Description">

<!-- Above fold - eager load (default) -->
<img src="hero.jpg" alt="Hero image">

Detected lazy-loader methods (lazy_method field)

scripts/parse_html.py classifies each image's lazy-loading mechanism via the lazy_method field on every image entry. Five values:

| lazy_method | Signal detected | Common stack | |---|---|---| | native | loading="lazy" HTML attribute | Modern browsers, plain HTML | | perfmatters | data-perfmatters-src/-srcset OR class perfmatters-lazy | WordPress + Perfmatters plugin | | ewww | data-ewww-src / data-eio OR class lazyload-eio | WordPress + EWWW Image Optimizer | | js-generic | data-src / data-lazy-src / data-original / data-srcset OR class lazyload/lazyloaded/lazy | Lazysizes, vanilla-lazyload, jQuery plugins | | none | Neither attribute nor class signal | Page is not lazy-loading this image |

When auditing image SEO, report lazy_method alongside loading so users know whether their site is using a JS-driven lazy-loader (in which case the native loading="lazy" attribute is intentionally absent — that is not a regression).

fetchpriority="high" for LCP Images

Add fetchpriority="high" to your hero/LCP image to prioritize its download in the browser's network queue:

<img src="hero.webp" fetchpriority="high" alt="Hero image description" width="1200" height="630">

Critical: Do NOT lazy-load above-the-fold/LCP images. Using loading="lazy" on LCP images directly harms LCP scores. Reserve loading="lazy" for below-the-fold images only.

decoding="async" for Non-LCP Images

Add decoding="async" to non-LCP images to prevent image decoding from blocking the main thread:

<img src="photo.webp" alt="Description" width="600" height="400" loading="lazy" decoding="async">

CLS Prevention

• width and height attributes set on all <img> elements
• aspect-ratio CSS as alternative
• Flag images without dimensions

<!-- Good - dimensions set -->
<img src="photo.jpg" width="800" height="600" alt="Description">

<!-- Good - CSS aspect ratio -->
<img src="photo.jpg" style="aspect-ratio: 4/3" alt="Description">

<!-- Bad - no dimensions -->
<img src="photo.jpg" alt="Description">

File Names

• Descriptive: blue-running-shoes.webp not IMG_1234.jpg
• Hyphenated, lowercase, no special characters
• Include relevant keywords

CDN Usage

• Check if images served from CDN (different domain, CDN headers)
• Recommend CDN for image-heavy sites
• Check for edge caching headers

Output

Image Audit Summary

| Metric | Status | Count | |--------|--------|-------| | Total Images | - | XX | | Missing Alt Text | ❌ | XX | | Oversized (>200KB) | ⚠️ | XX | | Wrong Format | ⚠️ | XX | | No Dimensions | ⚠️ | XX | | Not Lazy Loaded | ⚠️ | XX |

Prioritized Optimization List

Sorted by file size impact (largest savings first):

| Image | Current Size | Format | Issues | Est. Savings | |-------|--------------|--------|--------|--------------| | ... | ... | ... | ... | ... |

Recommendations

1. Convert X images to WebP format (est. XX KB savings)
2. Add alt text to X images
3. Add dimensions to X images
4. Enable lazy loading on X below-fold images
5. Compress X oversized images

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Image SERP Analysis

When DataForSEO MCP is available, enhance the image audit with competitive data.

/seo images serp <keyword>

Cross-reference on-page images with Google Images SERP rankings.

Workflow:

1. Fetch Google Images results via serp_google_images_live_advanced (depth=100)
2. Extract: top domains, image types, alt text patterns
3. Output competitor image SERP landscape

Output:

| Rank | Domain | Title/Alt | Image URL | Page URL | |------|--------|-----------|-----------|----------| | 1 | example.com | "Blue running shoes..." | .../shoes.webp | /products/... |

Analysis includes:

• Domain dominance: which sites own the most image positions (top 10 by count)
• Alt text patterns: common title/alt patterns in top-ranking images
• Format distribution: WebP vs JPEG vs PNG in top results
• Opportunity score: keywords where you have page rankings but no image presence

If DataForSEO MCP is not available, inform user and suggest installing the extension.

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Image File Optimization

Optimize image files for SEO: format conversion, metadata injection, compression.

/seo images optimize <path>

Optimize image file(s) for web and SEO. Converts to WebP/AVIF, injects IPTC metadata, compresses, and generates responsive variants.

Tools used (in order of preference):

• exiftool -- EXIF/IPTC/XMP read/write (install: sudo apt install libimage-exiftool-perl)
• cwebp -- WebP conversion (install: sudo apt install webp)
• ImageMagick convert -- Format conversion, resizing (pre-installed on most systems)
• FFmpeg -- Fallback for format conversion (pre-installed)

Before running: Check which tools are available with which exiftool cwebp convert ffmpeg.

Format Conversion

Convert images to modern formats with metadata preservation:

# WebP (recommended default) - with metadata preserved
cwebp -q 82 -metadata all input.jpg -o output.webp

# WebP via ImageMagick (fallback if cwebp not installed)
convert input.jpg -quality 82 output.webp

# AVIF via FFmpeg (slower encode, best compression)
ffmpeg -i input.jpg -c:v libaom-av1 -crf 30 -still-picture 1 output.avif

# Responsive variants (400w, 800w, 1200w)
convert input.jpg -resize 400x -quality 82 image-400.webp
convert input.jpg -resize 800x -quality 82 image-800.webp
convert input.jpg -resize 1200x -quality 82 image-1200.webp

Metadata Injection (IPTC for Google Rich Results)

Google Images displays IPTC Creator, Credit Line, and Copyright in search results. This is NOT a ranking factor but improves rich result display and brand attribution.

With exiftool (preferred):

# Read all metadata
exiftool image.jpg

# Inject IPTC + XMP metadata for Google Images rich results
exiftool \
  -IPTC:ObjectName="Product Photo Description" \
  -IPTC:Caption-Abstract="Detailed image description" \
  -IPTC:By-line="Brand Name Photography" \
  -IPTC:Credit="Brand Name" \
  -IPTC:CopyrightNotice="Copyright 2026 Brand Name" \
  -IPTC:Source="brandname.com" \
  -XMP:Title="Product Photo Description" \
  -XMP:Description="Detailed image description" \
  -XMP:Creator="Brand Name Photography" \
  -XMP:Rights="Copyright 2026 Brand Name" \
  image.jpg

# Batch inject to all images in directory
exiftool -overwrite_original \
  -IPTC:By-line="Brand Name" \
  -IPTC:CopyrightNotice="Copyright 2026 Brand Name" \
  *.jpg *.webp *.png

With ImageMagick (fallback):

identify -verbose image.jpg | head -50

convert input.jpg \
  -set comment "Product Photo Description" \
  -set IPTC:2:80 "Brand Name Photography" \
  -set IPTC:2:116 "Copyright 2026 Brand Name" \
  output.jpg

IMPORTANT: WebP supports EXIF and XMP but NOT IPTC natively. For WebP files, use XMP fields instead of IPTC. exiftool handles this conversion automatically.

AI-Generated Images: DigitalSourceType (Merchant Center requirement)

For product images produced by generative AI, Google Merchant Center requires IPTC DigitalSourceType: TrainedAlgorithmicMedia metadata. This is an operational policy requirement, not a ranking factor — feeds missing this label on AI-generated imagery can be disapproved.

Primary source: https://developers.google.com/search/docs/fundamentals/ai-optimization-guide (references the underlying Merchant Center policy on AI media labeling).

Audit command:

# Audit a directory for the IPTC label (counts: missing, ai, captured, etc.)
python scripts/iptc_ai_label.py audit ./images/ --json

# Audit a single image
python scripts/iptc_ai_label.py audit ./hero.webp --json

# Inject the AI label into an image
python scripts/iptc_ai_label.py inject ./ai-hero.webp \
    --source-type trainedAlgorithmicMedia

# Other vocabulary values:
#   compositeSynthetic  (mix of captured + AI elements)
#   digitalCapture      (fully captured photograph)

Raw exiftool equivalents (for ad-hoc usage):

# Inject manually
exiftool \
  -XMP-iptcExt:DigitalSourceType="https://cv.iptc.org/newscodes/digitalsourcetype/trainedAlgorithmicMedia" \
  ai-generated-product.jpg

# Audit: find images missing the label across a directory
exiftool -if 'not $XMP-iptcExt:DigitalSourceType' \
  -filename -DigitalSourceType *.jpg *.webp *.png

The IPTC vocabulary also defines:

• trainedAlgorithmicMedia — fully AI-generated (use this for diffusion-model product imagery)
• compositeSynthetic — mixes captured + AI-generated elements
• digitalCapture — fully captured photograph (no AI element)

When /seo images optimize is run on AI-generated assets, prompt the user to confirm the source type and inject the matching IPTC value automatically.

For AI-generated product titles and descriptions, Google Merchant Center also requires the AI-generated text to be separately specified and labeled in the feed. This is enforced at the feed layer, not the page layer — flag this in cross-reference with seo-ecommerce.

Metadata Audit

# Quick audit with exiftool
exiftool -IPTC:all -XMP:all -EXIF:ImageDescription image.jpg

# Batch audit - find images missing IPTC Creator
exiftool -if 'not $IPTC:By-line' -filename *.jpg *.webp *.png

Full Optimization Pipeline

For maximum image SEO, run this pipeline on each image:

1. Audit existing metadata: exiftool -IPTC:all -XMP:all image.jpg
2. Inject IPTC/XMP metadata: Creator, Copyright, Description
3. Convert to WebP: cwebp -q 82 -metadata all image.jpg -o image.webp
4. Generate responsive variants: 400w, 800w, 1200w
5. Verify metadata preserved: exiftool image.webp
6. Generate <picture> HTML: AVIF > WebP > JPEG fallback chain

What Matters vs What Doesn't for Google Images

| Factor | Impact | Where to Set | |--------|--------|--------------| | Alt text | CRITICAL (ranking) | HTML <img alt=""> | | Filename | HIGH (ranking) | File system (descriptive, hyphenated) | | Page context | HIGH (ranking) | Surrounding HTML content | | File size/speed | MEDIUM (indirect via CWV) | Compression + format conversion | | IPTC Creator/Copyright | LOW (display only) | Image file metadata | | EXIF camera data | NONE | Irrelevant for SEO | | IPTC Keywords | NONE | Google ignores these |

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Error Handling

| Scenario | Action | |----------|--------| | URL unreachable | Report connection error with status code. Suggest verifying URL and checking if site requires authentication. | | No images found on page | Report that no <img> elements were detected. Suggest checking if images are loaded via JavaScript or CSS background-image. | | Images behind CDN or authentication | Note that image files could not be directly accessed for size analysis. Report available metadata (alt text, dimensions, format from markup) and flag inaccessible resources. | | exiftool not installed | Fall back to ImageMagick for metadata. Recommend: sudo apt install libimage-exiftool-perl | | cwebp not installed | Fall back to ImageMagick or FFmpeg for WebP conversion. Recommend: sudo apt install webp | | DataForSEO MCP not available | Skip Image SERP Analysis section. Note extension is not installed. |