Auto Image Optimizer Documentation

SSP — Image Optimizer Pro (Docs)

SSP Documentation

SSP Image Optimizer Pro

Overview

SSP Image Optimizer Pro is a powerful local image optimization solution for WordPress. Compress images, convert between formats (PNG/JPG/WebP/GIF/BMP/AVIF), enable lazy loading, and auto-optimize uploads — all without external APIs for maximum speed and privacy.

100% Local: All optimization happens on your server. No images are sent to external services, ensuring complete privacy and faster processing.
Admin LocationDashboard → Image Optimizer (top-level menu)
RequirementsWordPress 5.8+, PHP 7.4+
Supported FormatsJPEG, PNG, GIF, WebP, BMP, AVIF

Dashboard

The dashboard provides an overview of your optimization statistics and server capabilities.

Statistics

Total ImagesAll images in your media library.
OptimizedImages that have been compressed.
PendingImages awaiting optimization.
WebPNumber of WebP versions generated.
ConvertedImages converted to a different format.
Space SavedTotal bytes saved across all optimizations.

Server Capabilities

The dashboard shows which image processing libraries and formats your server supports:

  • GD — PHP’s built-in image library (required).
  • ImageMagick — Advanced image processing (recommended).
  • WebP — Modern web format support.
  • AVIF — Next-gen compression format.
Note: AVIF support requires PHP 8.1+ with GD AVIF support, or ImageMagick with AVIF delegate.

Media Library

Browse, optimize, and convert your images from the Media Library tab.

Image Cards

Each image displays badges indicating its status:

FORMATCurrent file format (JPG, PNG, WebP, etc.).
OptimizedImage has been compressed.
PendingImage has not been optimized yet.
WebPWebP version is available.

Filters

  • Status — Filter by All, Pending, Optimized, or Has WebP.
  • Type — Filter by format (JPEG, PNG, GIF, WebP, BMP).
  • Search — Find images by filename.

Image Actions

  • Optimize — Compress the image with current settings.
  • Convert — Change the image to a different format.
  • Restore — Restore from backup (if available).

Bulk Operations

  1. Select images using checkboxes (or click Select All).
  2. Click Optimize to compress selected images.
  3. Or click Convert to change their format.
Tip: Use Quick Optimize All on the dashboard to optimize all pending images in one click.

Format Conversion

Convert images between any supported formats for optimal performance.

Bulk Conversion

  1. Go to the Convert tab.
  2. Select source format (or “All Formats”).
  3. Select target format (WebP, JPEG, PNG, or AVIF).
  4. Click Convert All.

Format Comparison

JPEGBest for photos. Lossy compression, excellent size reduction. No transparency. Universal browser support.
PNGBest for graphics/logos. Lossless compression, supports transparency. Larger files for photos.
WebPBest for all web images. 26% smaller than JPEG. Supports transparency. 97% browser support.
AVIFBest quality/size ratio. 50% smaller than JPEG. Supports transparency. 92% browser support.
GIFBest for simple animations. Limited to 256 colors. Universal support.
Recommendation: Convert photos to WebP for the best balance of quality, file size, and browser compatibility.

Keep Both Formats

When enabled in Settings, the plugin keeps both the original and converted file. This provides a fallback for older browsers that don’t support WebP/AVIF.

Compression Settings

Control how aggressively images are compressed.

Compression Modes

LosslessMaximum quality (95%). Minimal file size reduction. Best for archival.
BalancedRecommended. Good quality (80-85%) with significant size reduction.
AggressiveMaximum compression (65-70%). Visible quality loss on close inspection.
CustomSet individual quality levels for each format.

Quality Sliders

When using Custom mode, adjust quality for each format individually:

  • JPEG Quality — 50-100% (default: 82%)
  • PNG Quality — 50-100% (default: 82%)
  • WebP Quality — 50-100% (default: 80%)
  • AVIF Quality — 50-100% (default: 75%)
Tip: Quality below 70% may show visible artifacts. Start with 80% and reduce if needed.

Auto-Processing

Automatically optimize and convert images as they’re uploaded.

Auto-Optimize on Upload

When enabled, every image uploaded to the media library is automatically compressed using your current quality settings.

Auto-Convert on Upload

When enabled, uploaded images are automatically converted to your preferred format (WebP, JPEG, PNG, or AVIF).

Optimize Thumbnails

When enabled, all generated thumbnail sizes are also optimized and converted, not just the original image.

SettingSettings tab → Auto-Processing section
DefaultAuto-Optimize enabled, Auto-Convert disabled
Recommended: Enable Auto-Optimize and Optimize Thumbnails for hands-off optimization.

WebP & AVIF Generation

Generate modern image formats alongside your original images.

Also Create WebP Versions

When enabled, a WebP copy is created for every JPEG/PNG image. This doesn’t replace the original — both files exist side by side.

Also Create AVIF Versions

Same as WebP, but creates AVIF versions for even smaller file sizes. Requires server AVIF support.

Serve WebP Automatically

When enabled, the plugin automatically serves WebP images to browsers that support them, falling back to the original format for older browsers.

How It WorksThe plugin checks the browser’s Accept header and rewrites image URLs to WebP versions when available.
FallbackBrowsers without WebP support receive the original JPEG/PNG.
Note: Some caching plugins may interfere with automatic WebP serving. Clear cache after enabling.

Lazy Loading

Defer loading of off-screen images to improve page load speed.

How It Works

  • Images below the viewport are loaded with a placeholder.
  • As the user scrolls, images are loaded just before they enter view.
  • Uses native browser lazy loading with IntersectionObserver fallback.

Load Threshold

Controls how far before reaching the viewport images start loading (in pixels). Default: 200px.

  • 0px — Load exactly when entering viewport.
  • 200px — Load 200px before entering viewport (recommended).
  • 500px+ — Pre-load images further in advance.

Excluding Images

Add the class no-lazy to any image to exclude it from lazy loading:

<img src="hero.jpg" class="no-lazy" alt="Hero image">
Best practice: Exclude above-the-fold images (hero images, logos) from lazy loading to prevent layout shift.

Image Resizing

Automatically resize large images to reasonable dimensions.

Resize Large Images

When enabled, images exceeding the maximum dimensions are automatically scaled down during optimization.

Maximum Dimensions

Max WidthMaximum allowed width in pixels (default: 2560px)
Max HeightMaximum allowed height in pixels (default: 2560px)

Images are resized proportionally — aspect ratio is always preserved.

Note: Resizing is one-way. If you need larger versions later, restore from backup or re-upload.

Backups & Safety

Protect your original images with automatic backups.

Backup Original Images

When enabled, the original unoptimized image is saved before any compression or conversion. You can restore it at any time.

Backup Location/wp-content/uploads/ssp-image-backups/
Naming{attachment_id}_{filename}
ProtectionDirectory is protected with .htaccess to prevent direct access.

Preserve EXIF Metadata

When enabled, camera information, GPS data, and other metadata is preserved. When disabled, metadata is stripped to reduce file size.

Skip Already Optimized

When enabled, images that have already been optimized are skipped during bulk operations to save time.

Restoring Images

  1. Go to the Media Library tab.
  2. Find the image you want to restore.
  3. Click the Restore button (only appears if backup exists).
Tip: Keep backups enabled until you’re confident with your quality settings.

Tools

Maintenance utilities for managing your optimized images.

Regenerate WebP Images

Recreates all WebP versions using current quality settings. Useful after changing WebP quality.

Manage Backups

  • View current backup folder size.
  • Click Clear All Backups to permanently delete all backup files.
Warning: Clearing backups is permanent. You won’t be able to restore original images afterward.

Reset Statistics

Resets all optimization counters (total optimized, space saved, etc.) to zero. Does not affect actual images.

CDN URL

If you use a CDN, enter your CDN URL in Settings. Image URLs will be rewritten to use your CDN domain.

Examplehttps://cdn.yoursite.com

FAQ & Troubleshooting

Images not being optimized?

  • Check that GD or ImageMagick is installed.
  • Verify the image format is supported.
  • Check “Skip Already Optimized” isn’t blocking re-optimization.
  • Ensure sufficient disk space and PHP memory.

WebP not being served?

  • Verify “Serve WebP Automatically” is enabled.
  • Check that WebP files exist in uploads folder.
  • Clear any caching plugins.
  • Check browser supports WebP (test in Chrome).

AVIF conversion failing?

  • AVIF requires PHP 8.1+ with GD AVIF support.
  • Or ImageMagick compiled with AVIF delegate.
  • Check server capabilities on Dashboard.

Images look too compressed?

  • Switch to “Balanced” or “Lossless” mode.
  • Increase quality sliders (try 85%+).
  • Restore from backup and re-optimize.

What happens to thumbnails?

When “Optimize Thumbnails” is enabled, all WordPress-generated sizes (thumbnail, medium, large, etc.) are also optimized. If you convert an image to a different format, thumbnails are regenerated in the new format.

Can I use this with other image plugins?

Generally yes, but disable auto-optimization in one plugin to avoid double-processing. This plugin handles optimization locally without external APIs, so it won’t conflict with CDN services.

How much space can I save?

Typical savings with Balanced mode: JPEG 20-40%, PNG 30-60%, converting to WebP saves an additional 25-35% beyond JPEG.