Disable Image Compression

Property	Value
description	Force WordPress generated image quality to 100.
tags	lib, php, wp, oop
rating

Human: 3 - Mixed authorship

Roughly half AI, half human. Core content reviewed, but minor risk remains.

Overview

Force WordPress image quality to 100 for generated image derivatives.

The snippet hooks into the editor quality and format-specific quality filters for JPEG, WebP, and AVIF. Use it when image optimization is handled elsewhere and WordPress should not apply its default compression during upload processing.

Variants

Procedural

Add Macro

Add wp-disable-image-compression macro.

<?php
/**
 * Disable WordPress image compression on upload.
 */

/**
 * Force max image quality.
 */
if ( ! function_exists( 'mac_force_max_image_quality' ) ) {

    function mac_force_max_image_quality( int $quality ): int {
        return 100;
    }
}

/**
 * Apply max quality to all supported formats.
 */
add_filter( 'wp_editor_set_quality', 'mac_force_max_image_quality', 10, 1 );
add_filter( 'jpeg_quality', 'mac_force_max_image_quality', 10, 1 );
add_filter( 'webp_upload_quality', 'mac_force_max_image_quality', 10, 1 );
add_filter( 'avif_upload_quality', 'mac_force_max_image_quality', 10, 1 );

OOP

Add Macro

Add wp-disable-image-compression--oop macro.

<?php
/**
 * Disable WordPress image compression on upload.
 *
 * Forces quality to 100 for formats handled by WordPress.
 * Intended to defer optimization to external tools (e.g. ShortPixel).
 *
 * @package mac-core
 */

declare(strict_types=1);

namespace MacCore\Services\Media;

use MacCore\Contracts\Service;

final class DisableImageCompression implements Service
{
    public function register(): void
    {
        // Editor image quality (covers JPEG & WebP in modern WP).
        \add_filter(
            'wp_editor_set_quality',
            [$this, 'force_max_quality'],
            10,
            1
        );

        // Legacy JPEG quality filter.
        \add_filter(
            'jpeg_quality',
            [$this, 'force_max_quality'],
            10,
            1
        );

        // Modern formats.
        \add_filter(
            'webp_upload_quality',
            [$this, 'force_max_quality'],
            10,
            1
        );

        \add_filter(
            'avif_upload_quality',
            [$this, 'force_max_quality'],
            10,
            1
        );
    }

    public function force_max_quality( int $quality ): int
    {
        return 100;
    }
}