| 1 |
<?php |
| 2 |
/** |
| 3 |
* Metasync_Image_Converter |
| 4 |
* Converts uploaded JPEG/PNG images to WebP or AVIF on upload. |
| 5 |
* Supports "replace" and "alongside" strategies. |
| 6 |
* |
| 7 |
* @package Search Atlas SEO |
| 8 |
* @copyright Copyright (C) 2021-2025, Search Atlas Group - [email protected] |
| 9 |
* @since 2.6.0 |
| 10 |
*/ |
| 11 |
|
| 12 |
if (!defined('ABSPATH')) { |
| 13 |
exit; |
| 14 |
} |
| 15 |
|
| 16 |
class Metasync_Image_Converter { |
| 17 |
|
| 18 |
private array $settings; |
| 19 |
|
| 20 |
private const SUPPORTED_MIMES = [ |
| 21 |
'image/jpeg', |
| 22 |
'image/png', |
| 23 |
]; |
| 24 |
|
| 25 |
private const EXT_AVIF = '.avif'; |
| 26 |
private const EXT_WEBP = '.webp'; |
| 27 |
private const ORIGINAL_EXT_PATTERN = '/\.(jpe?g|png)$/i'; |
| 28 |
|
| 29 |
/** |
| 30 |
* Get file extension for a given format. |
| 31 |
*/ |
| 32 |
private static function get_format_extension(string $format): string { |
| 33 |
return $format === 'avif' ? self::EXT_AVIF : self::EXT_WEBP; |
| 34 |
} |
| 35 |
|
| 36 |
public function __construct(array $settings) { |
| 37 |
$this->settings = $settings; |
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|
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// Fires after WP generates all thumbnail sizes |
| 40 |
add_filter('wp_generate_attachment_metadata', [$this, 'convert_on_upload'], 10, 2); |
| 41 |
|
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// If "alongside" strategy, rewrite <img> tags to <picture> |
| 43 |
if ($settings['conversion_strategy'] === 'alongside') { |
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// Core WordPress |
| 45 |
add_filter('the_content', [$this, 'rewrite_to_picture_tags'], 20); |
| 46 |
add_filter('post_thumbnail_html', [$this, 'rewrite_to_picture_tags'], 20); |
| 47 |
add_filter('widget_text', [$this, 'rewrite_to_picture_tags'], 20); |
| 48 |
|
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// WooCommerce frontend images |
| 50 |
add_filter('woocommerce_single_product_image_thumbnail_html', [$this, 'rewrite_to_picture_tags'], 20); |
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add_filter('woocommerce_product_get_image', [$this, 'rewrite_to_picture_tags'], 20); |
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add_filter('woocommerce_cart_item_thumbnail', [$this, 'rewrite_to_picture_tags'], 20); |
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add_filter('woocommerce_placeholder_img', [$this, 'rewrite_to_picture_tags'], 20); |
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} |
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} |
| 56 |
|
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/** |
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* Hook into metadata generation to convert the main file and all sub-sizes. |
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*/ |
| 60 |
public function convert_on_upload(array $metadata, int $attachment_id): array { |
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$file = get_attached_file($attachment_id); |
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$mime = get_post_mime_type($attachment_id); |
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|
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if (!$file || !in_array($mime, self::SUPPORTED_MIMES, true)) { |
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return $metadata; |
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} |
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|
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// Check exclusions |
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if ($this->is_excluded($file)) { |
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return $metadata; |
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} |
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|
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$format = $this->settings['conversion_format']; |
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$quality = (int) $this->settings['conversion_quality']; |
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$strategy = $this->settings['conversion_strategy']; |
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|
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// Convert main/full file |
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$converted = $this->convert_file($file, $format, $quality); |
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|
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if ($converted && $strategy === 'replace') { |
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$this->replace_original($attachment_id, $file, $converted, $metadata, $format); |
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} |
| 83 |
|
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// Convert sub-sizes (thumbnails, medium, large, etc.) |
| 85 |
if (!empty($this->settings['convert_existing_sizes']) && !empty($metadata['sizes'])) { |
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$upload_dir = dirname($file); |
| 87 |
foreach ($metadata['sizes'] as $size_name => &$size_data) { |
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$size_file = $upload_dir . '/' . $size_data['file']; |
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$size_converted = $this->convert_file($size_file, $format, $quality); |
| 90 |
|
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if ($size_converted && $strategy === 'replace') { |
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@unlink($size_file); |
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$size_data['file'] = basename($size_converted); |
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$size_data['mime-type'] = "image/{$format}"; |
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} |
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} |
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unset($size_data); |
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} |
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|
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// Store converted format in meta for later use by picture tag rewriter |
| 101 |
if ($converted && $strategy === 'alongside') { |
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update_post_meta($attachment_id, '_metasync_converted_format', $format); |
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} |
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|
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return $metadata; |
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} |
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|
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// ── Static Methods for External Use (Batch Optimizer, AJAX) ── |
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|
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/** |
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* Convert an existing attachment to next-gen format. |
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* Used by batch optimizer and single-image AJAX actions. |
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*/ |
| 114 |
public static function convert_attachment(int $attachment_id, array $settings): bool { |
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$file = get_attached_file($attachment_id); |
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$mime = get_post_mime_type($attachment_id); |
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|
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if (!$file || !in_array($mime, self::SUPPORTED_MIMES, true)) { |
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return false; |
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} |
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|
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$format = $settings['conversion_format'] ?? 'webp'; |
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$quality = (int) ($settings['conversion_quality'] ?? 82); |
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$strategy = $settings['conversion_strategy'] ?? 'alongside'; |
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|
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// Store original file size before conversion for savings display |
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$original_size = filesize($file); |
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|
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$converted = self::do_convert_file($file, $format, $quality); |
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if (!$converted) { |
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return false; |
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} |
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|
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// Store original size meta for savings calculation |
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if ($original_size) { |
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update_post_meta($attachment_id, '_metasync_original_filesize', $original_size); |
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} |
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|
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if ($strategy === 'replace') { |
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$metadata = wp_get_attachment_metadata($attachment_id); |
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if ($metadata) { |
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self::do_replace_original($attachment_id, $file, $converted, $metadata, $format); |
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wp_update_attachment_metadata($attachment_id, $metadata); |
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} |
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} |
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|
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// Convert sub-sizes |
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if (!empty($settings['convert_existing_sizes'])) { |
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$metadata = wp_get_attachment_metadata($attachment_id); |
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if ($metadata && !empty($metadata['sizes'])) { |
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$upload_dir = dirname($file); |
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foreach ($metadata['sizes'] as $size_name => &$size_data) { |
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$size_file = $upload_dir . '/' . $size_data['file']; |
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$size_converted = self::do_convert_file($size_file, $format, $quality); |
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|
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if ($size_converted && $strategy === 'replace') { |
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@unlink($size_file); |
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$size_data['file'] = basename($size_converted); |
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$size_data['mime-type'] = "image/{$format}"; |
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} |
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} |
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unset($size_data); |
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if ($strategy === 'replace') { |
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wp_update_attachment_metadata($attachment_id, $metadata); |
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} |
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} |
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} |
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|
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update_post_meta($attachment_id, '_metasync_converted_format', $format); |
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return true; |
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} |
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|
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/** |
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* Revert an attachment's conversion (alongside strategy only). |
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* Deletes the converted files and removes the meta marker. |
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*/ |
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public static function revert_attachment(int $attachment_id): bool { |
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$format = get_post_meta($attachment_id, '_metasync_converted_format', true); |
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if (!$format) { |
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return false; |
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} |
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|
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$file = get_attached_file($attachment_id); |
| 184 |
if (!$file) { |
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return false; |
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} |
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|
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// Check if original still exists (alongside strategy) |
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if (!file_exists($file)) { |
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return false; // Cannot revert replace strategy |
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} |
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|
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$ext = self::get_format_extension($format); |
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|
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// Delete converted full-size file |
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$converted_path = preg_replace(self::ORIGINAL_EXT_PATTERN, $ext, $file); |
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if ($converted_path && file_exists($converted_path)) { |
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@unlink($converted_path); |
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} |
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|
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// Delete converted sub-sizes |
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$metadata = wp_get_attachment_metadata($attachment_id); |
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if ($metadata && !empty($metadata['sizes'])) { |
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$upload_dir = dirname($file); |
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foreach ($metadata['sizes'] as $size_data) { |
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$size_converted = preg_replace(self::ORIGINAL_EXT_PATTERN, $ext, $upload_dir . '/' . $size_data['file']); |
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if ($size_converted && file_exists($size_converted)) { |
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@unlink($size_converted); |
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} |
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} |
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} |
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|
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delete_post_meta($attachment_id, '_metasync_converted_format'); |
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delete_post_meta($attachment_id, '_metasync_original_filesize'); |
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return true; |
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} |
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|
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// ── Core Conversion (static, reusable) ── |
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|
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/** |
| 221 |
* Convert a single image file. Returns path to converted file or null on failure. |
| 222 |
*/ |
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protected static function do_convert_file(string $source, string $format, int $quality): ?string { |
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if (!file_exists($source)) { |
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return null; |
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} |
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|
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$ext = self::get_format_extension($format); |
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$dest = preg_replace(self::ORIGINAL_EXT_PATTERN, $ext, $source); |
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|
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// Try Imagick first, fall back to GD if it fails (e.g. missing encode delegate) |
| 232 |
if (extension_loaded('imagick')) { |
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try { |
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$result = self::do_convert_with_imagick($source, $dest, $format, $quality); |
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if ($result) { |
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return $result; |
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} |
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} catch (\Exception $e) { |
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error_log('[MetaSync Media Opt] Imagick conversion failed, trying GD: ' . $e->getMessage()); |
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} |
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} |
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|
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if (extension_loaded('gd')) { |
| 244 |
try { |
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return self::do_convert_with_gd($source, $dest, $format, $quality); |
| 246 |
} catch (\Exception $e) { |
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error_log('[MetaSync Media Opt] GD conversion failed: ' . $e->getMessage()); |
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} |
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} |
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|
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return null; |
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} |
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|
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private static function do_convert_with_imagick(string $src, string $dest, string $fmt, int $q): ?string { |
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$img = new \Imagick($src); |
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$img->setImageFormat($fmt === 'avif' ? 'avif' : 'webp'); |
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$img->setImageCompressionQuality($q); |
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$img->stripImage(); |
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|
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if ($img->writeImage($dest)) { |
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$img->destroy(); |
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return $dest; |
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} |
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|
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$img->destroy(); |
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return null; |
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} |
| 268 |
|
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private static function do_convert_with_gd(string $src, string $dest, string $fmt, int $q): ?string { |
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$info = getimagesize($src); |
| 271 |
if (!$info) { |
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return null; |
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} |
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|
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$gd_img = match ($info['mime']) { |
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'image/jpeg' => imagecreatefromjpeg($src), |
| 277 |
'image/png' => imagecreatefrompng($src), |
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default => null, |
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}; |
| 280 |
|
| 281 |
if (!$gd_img) { |
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return null; |
| 283 |
} |
| 284 |
|
| 285 |
if ($info['mime'] === 'image/png') { |
| 286 |
imagepalettetotruecolor($gd_img); |
| 287 |
imagealphablending($gd_img, true); |
| 288 |
imagesavealpha($gd_img, true); |
| 289 |
} |
| 290 |
|
| 291 |
$success = match ($fmt) { |
| 292 |
'webp' => imagewebp($gd_img, $dest, $q), |
| 293 |
'avif' => function_exists('imageavif') ? imageavif($gd_img, $dest, $q) : false, |
| 294 |
default => false, |
| 295 |
}; |
| 296 |
|
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imagedestroy($gd_img); |
| 298 |
return $success ? $dest : null; |
| 299 |
} |
| 300 |
|
| 301 |
/** |
| 302 |
* Replace original file with converted version. |
| 303 |
*/ |
| 304 |
private static function do_replace_original(int $id, string $old_path, string $new_path, array &$meta, string $fmt): void { |
| 305 |
@unlink($old_path); |
| 306 |
|
| 307 |
wp_update_post([ |
| 308 |
'ID' => $id, |
| 309 |
'post_mime_type' => "image/{$fmt}", |
| 310 |
]); |
| 311 |
|
| 312 |
update_attached_file($id, $new_path); |
| 313 |
$meta['file'] = _wp_relative_upload_path($new_path); |
| 314 |
} |
| 315 |
|
| 316 |
// ── Instance Wrappers (Upload Hook) ── |
| 317 |
|
| 318 |
/** |
| 319 |
* Instance wrapper around static conversion method. |
| 320 |
*/ |
| 321 |
private function convert_file(string $source, string $format, int $quality): ?string { |
| 322 |
return self::do_convert_file($source, $format, $quality); |
| 323 |
} |
| 324 |
|
| 325 |
/** |
| 326 |
* Instance wrapper around static replace method. |
| 327 |
*/ |
| 328 |
private function replace_original(int $id, string $old_path, string $new_path, array &$meta, string $fmt): void { |
| 329 |
self::do_replace_original($id, $old_path, $new_path, $meta, $fmt); |
| 330 |
} |
| 331 |
|
| 332 |
/** |
| 333 |
* Rewrite <img> tags to <picture> with next-gen source. |
| 334 |
*/ |
| 335 |
public function rewrite_to_picture_tags(string $content): string { |
| 336 |
if (empty($content)) { |
| 337 |
return $content; |
| 338 |
} |
| 339 |
|
| 340 |
// Skip if already wrapped in <picture> (avoid double-wrapping from multiple filters) |
| 341 |
if (strpos($content, '<picture>') !== false) { |
| 342 |
return $content; |
| 343 |
} |
| 344 |
|
| 345 |
return preg_replace_callback('/<img\s[^>]+>/i', function ($matches) { |
| 346 |
$img_tag = $matches[0]; |
| 347 |
|
| 348 |
// Check if this image should be excluded |
| 349 |
if ($this->is_tag_excluded($img_tag)) { |
| 350 |
return $img_tag; |
| 351 |
} |
| 352 |
|
| 353 |
// Extract src |
| 354 |
if (!preg_match('/src=["\']([^"\']+)["\']/i', $img_tag, $src_match)) { |
| 355 |
return $img_tag; |
| 356 |
} |
| 357 |
|
| 358 |
$original_src = $src_match[1]; |
| 359 |
$format = $this->settings['conversion_format']; |
| 360 |
$ext = self::get_format_extension($format); |
| 361 |
|
| 362 |
// Build the converted file URL |
| 363 |
$converted_url = preg_replace(self::ORIGINAL_EXT_PATTERN, $ext, $original_src); |
| 364 |
|
| 365 |
// Only wrap if the converted URL is different |
| 366 |
if ($converted_url === $original_src) { |
| 367 |
return $img_tag; |
| 368 |
} |
| 369 |
|
| 370 |
// Verify the converted file actually exists on disk before rewriting |
| 371 |
$converted_path = $this->url_to_path($converted_url); |
| 372 |
if (!$converted_path || !file_exists($converted_path)) { |
| 373 |
return $img_tag; |
| 374 |
} |
| 375 |
|
| 376 |
$mime = $format === 'avif' ? 'image/avif' : 'image/webp'; |
| 377 |
|
| 378 |
// Also handle srcset if present |
| 379 |
$source_srcset = ''; |
| 380 |
if (preg_match('/srcset=["\']([^"\']+)["\']/i', $img_tag, $srcset_match)) { |
| 381 |
$converted_srcset = preg_replace('/\.(jpe?g|png)/i', $ext, $srcset_match[1]); |
| 382 |
$source_srcset = sprintf(' srcset="%s"', esc_attr($converted_srcset)); |
| 383 |
} |
| 384 |
|
| 385 |
// Extract sizes attribute to pass to <source> |
| 386 |
$sizes_attr = ''; |
| 387 |
if (preg_match('/sizes=["\']([^"\']+)["\']/i', $img_tag, $sizes_match)) { |
| 388 |
$sizes_attr = sprintf(' sizes="%s"', esc_attr($sizes_match[1])); |
| 389 |
} |
| 390 |
|
| 391 |
return sprintf( |
| 392 |
'<picture><source type="%s"%s%s>%s</picture>', |
| 393 |
esc_attr($mime), |
| 394 |
$source_srcset ?: sprintf(' srcset="%s"', esc_attr($converted_url)), |
| 395 |
$sizes_attr, |
| 396 |
$img_tag |
| 397 |
); |
| 398 |
}, $content); |
| 399 |
} |
| 400 |
|
| 401 |
/** |
| 402 |
* Convert a URL to a local file path. Returns null if URL is external. |
| 403 |
*/ |
| 404 |
private function url_to_path(string $url): ?string { |
| 405 |
$upload_dir = wp_get_upload_dir(); |
| 406 |
$base_url = $upload_dir['baseurl']; |
| 407 |
$base_path = $upload_dir['basedir']; |
| 408 |
|
| 409 |
if (strpos($url, $base_url) === 0) { |
| 410 |
return str_replace($base_url, $base_path, $url); |
| 411 |
} |
| 412 |
|
| 413 |
return null; |
| 414 |
} |
| 415 |
|
| 416 |
/** |
| 417 |
* Check if a file path matches exclusion patterns. |
| 418 |
*/ |
| 419 |
private function is_excluded(string $file): bool { |
| 420 |
$exclude_urls = array_filter(array_map('trim', explode(',', $this->settings['exclude_urls'] ?? ''))); |
| 421 |
if (empty($exclude_urls)) { |
| 422 |
return false; |
| 423 |
} |
| 424 |
|
| 425 |
foreach ($exclude_urls as $pattern) { |
| 426 |
if (stripos($file, $pattern) !== false) { |
| 427 |
return true; |
| 428 |
} |
| 429 |
} |
| 430 |
return false; |
| 431 |
} |
| 432 |
|
| 433 |
/** |
| 434 |
* Check if an img tag has an excluded CSS class. |
| 435 |
*/ |
| 436 |
private function is_tag_excluded(string $tag): bool { |
| 437 |
$exclude_classes = array_filter(array_map('trim', explode(',', $this->settings['exclude_classes'] ?? ''))); |
| 438 |
if (empty($exclude_classes)) { |
| 439 |
return false; |
| 440 |
} |
| 441 |
|
| 442 |
if (preg_match('/class=["\']([^"\']+)["\']/i', $tag, $class_match)) { |
| 443 |
$classes = explode(' ', $class_match[1]); |
| 444 |
foreach ($exclude_classes as $excluded) { |
| 445 |
if (in_array($excluded, $classes, true)) { |
| 446 |
return true; |
| 447 |
} |
| 448 |
} |
| 449 |
} |
| 450 |
return false; |
| 451 |
} |
| 452 |
|
| 453 |
} |
| 454 |
|
