WP Image Compress To WebP

WordPress plugin that automatically converts newly uploaded JPG, JPEG, and PNG images into WebP format at quality 80, then removes the original source files.

Overview

This plugin hooks into the WordPress media upload pipeline and:

• Converts original uploaded images to WebP
• Converts generated intermediate sizes (thumbnails, medium, large, etc.) to WebP
• Deletes the original non-WebP files after successful conversion
• Updates attachment metadata so generated sizes point to WebP files

It also includes a lightweight admin dashboard for local license key management.

Features

• Automatic conversion of newly uploaded jpg, jpeg, and png files
• WebP quality fixed at 80 (current implementation)
• Original and intermediate files are removed only after successful WebP generation
• Uses Imagick when available, with fallback to GD (imagewebp)
• Admin page under WebP Compress for license activation/deactivation
• Dashboard button to convert existing JPEG/PNG media to WebP with progress
• Dashboard button to regenerate thumbnails for all image attachments with progress
• Nonce-protected license form handling and capability checks (manage_options)

Requirements

• WordPress (plugin-based installation)
• PHP with at least one of:
  • Imagick extension, or
  • GD extension with WebP support (imagewebp)

Without these capabilities, image conversion will fail and original uploads will remain unchanged.

Installation

1. Copy wp-image-compress-to-webp into wp-content/plugins/.
2. In WordPress admin, go to Plugins and activate WP Image Compress To WebP.
3. Open WebP Compress in the admin menu to review dashboard and license status.
4. Upload images through Media Library as usual.

Usage

Automatic conversion flow

After activation, no additional setup is required for conversion:

1. Upload a supported image (jpg, jpeg, png).
2. Plugin attempts to generate a .webp version at quality 80.
3. On success, the original uploaded file is deleted.
4. Generated image sizes are also converted to WebP and updated in metadata.

License dashboard

Go to WebP Compress in WP Admin:

• Enter a license key and click Save & Activate License
• Click Deactivate License to clear stored key and status

Note: Current license activation is local format validation only (no external API validation).

Convert existing media

Go to WebP Compress in WP Admin and click Convert Old Images to WebP.

• The dashboard shows conversion progress for old JPEG/PNG attachments.
• Existing items are processed in batches to avoid request timeouts.

Regenerate all thumbnails

Go to WebP Compress in WP Admin and click Regenerate All Thumbnails.

• The dashboard shows regeneration progress for image attachments.
• Items are processed in batches to avoid request timeouts.

Current behavior and limitations

• New uploads are converted automatically; existing media can be converted manually from the dashboard.
• Only jpg, jpeg, and png are handled.
• Conversion quality defaults to 80 and can be adjusted via the wicw_webp_quality filter.
• No remote license server check is implemented yet.

Project structure

• wp-image-compress-to-webp.php — Plugin bootstrap and module loading
• src/image-converter.php — Upload and intermediate size conversion logic
• src/license.php — License key storage and local validation
• src/admin.php — Admin menu, dashboard rendering, and asset loading
• assets/admin-dashboard.css — Dashboard styling

Security notes

• Direct file access is blocked with ABSPATH checks.
• License actions require admin capability checks.
• Form submissions are protected using WordPress nonces.
• User-provided license input is sanitized before storage.

Version

Current plugin version: 1.0.0