AVIF Local Support

Built by a Boston photographer for site owners who care about visual quality and full control. This plugin prioritizes image quality over everything else — no subscriptions, no external services.

Features

• Local Processing — All conversion happens on your server. No subscriptions or external API calls. Works great on a shared CPU with 2GB RAM.
• Quality First — Uses LANCZOS resizing, preserves ICC color profiles, and keeps EXIF/XMP/IPTC metadata intact.
• Fully Tunable — Control quality (0–100), speed (0–10), chroma subsampling (4:2:0, 4:2:2, 4:4:4), and bit depth (8/10/12-bit).
• Smart Fallback — Serves AVIF to supported browsers, JPEG to everyone else via picture elements.
• Automatic Conversion — Convert on upload or via daily scheduled background scans.
• LQIP Placeholders — Generate ThumbHash-based low-quality image placeholders for smooth loading.

How It Works

Front end: The plugin wraps your img tags in picture elements with an AVIF source. Browsers that support AVIF load the smaller, higher-quality file — others gracefully fall back to JPEG.

Conversion: Uses ImageMagick CLI (fastest), Imagick PHP extension (high quality), or GD Library (fallback) to convert JPEGs to AVIF on upload or via background jobs.

LQIP: Generates compact (~30 byte) ThumbHash placeholders that display instantly while images load.

Server Setup

The plugin supports three conversion engines, in order of preference:

ImageMagick CLI (Fastest, Recommended)

Uses the ImageMagick command-line binary directly:

• System binary: ImageMagick 7.x built with HEIF/AVIF support (via libheif)
• No PHP extension required
• Benefits: Fastest performance, LANCZOS resizing, full metadata preservation (EXIF, XMP, IPTC, ICC)
• Typical paths: /usr/bin/magick, /usr/local/bin/magick, or Homebrew on macOS

To verify AVIF support:

magick -list format | grep -i avif

Imagick PHP Extension (High Quality)

Uses the PHP Imagick extension:

• PHP extension: imagick
• System libraries: ImageMagick built with HEIF/AVIF support (via libheif)
• Benefits: LANCZOS resizing, full metadata preservation (EXIF, XMP, IPTC, ICC), color profile handling

To install on Ubuntu/Debian:

apt install php-imagick imagemagick libheif-dev

GD Library (Fallback)

Uses PHP’s built-in GD library:

• PHP extension: gd built with AVIF support (provides imageavif on PHP 8.1+)
• Note: Some distro builds omit AVIF support; limited metadata preservation

MIME Type Configuration

Ensure your web server is configured to serve .avif files as image/avif.

Documentation

• ImageMagick installation
• PHP Imagick installation
• PHP GD installation
• ImageMagick format support

Need help with setup?

If you’re not sure what to install or upgrade, copy your Server Diagnostics from the plugin status/tools screen (or run wp avif status --format=json) and paste it into an LLM.

Example prompt:

I need AVIF support for WordPress. Based on this diagnostics output, give me step-by-step commands to install or upgrade ImageMagick, libheif, and PHP Imagick on my server.

After applying changes, verify with:

wp avif status
magick -list format | grep -i avif
WP-CLI Commands

Manage AVIF conversions from the command line.

Status

Show system status and AVIF support diagnostics:

wp avif status
wp avif status --format=json

Convert

Convert JPEG images to AVIF format:

wp avif convert --all
wp avif convert 123
wp avif convert --all --dry-run

Options:

• — Specific attachment ID to convert
• --all — Convert all attachments missing AVIF versions
• --dry-run — Show what would be converted without actually converting

Statistics

Show AVIF conversion statistics:

wp avif stats
wp avif stats --format=json

Logs

View or clear conversion logs:

wp avif logs
wp avif logs --limit=50
wp avif logs --clear

Options:

• --clear — Clear all logs
• --limit= — Number of logs to show (default: 20)

Delete

Delete AVIF files for an attachment or all attachments:

wp avif delete 123
wp avif delete --all --yes

Options:

• — Attachment ID to delete AVIF files for
• --all — Delete all AVIF files in the media library
• --yes — Skip confirmation prompt when using –all

LQIP Commands

Manage LQIP (ThumbHash) placeholders:

wp lqip stats
wp lqip generate --all --force
wp lqip generate 123
wp lqip delete --all --yes

For more information, visit wp-cli.org.

Contributing

Contributions welcome! Please submit issues and pull requests on GitHub.

License

GPL v2 or later — View License