Convert uploaded PNG files to AVIF or WebP

plugins/webp-uploads/helper.php

@@ -29,12 +29,14 @@ function webp_uploads_get_upload_image_mime_transforms(): array {
 		'image/jpeg' => array( 'image/' . $output_format ),
 		'image/webp' => array( 'image/webp' ),
 		'image/avif' => array( 'image/avif' ),
+		'image/png'  => array( 'image/' . $output_format ),
 	);
 
 	// Check setting for whether to generate both JPEG and the modern output format.
 	if ( webp_uploads_is_jpeg_fallback_enabled() ) {
 		$default_transforms = array(
 			'image/jpeg'              => array( 'image/jpeg', 'image/' . $output_format ),
+			'image/png'               => array( 'image/png', 'image/' . $output_format ),
 			'image/' . $output_format => array( 'image/' . $output_format, 'image/jpeg' ),
 		);
 	}

plugins/webp-uploads/picture-element.php

@@ -56,7 +56,7 @@ function webp_uploads_wrap_image_in_picture( string $image, string $context, int
 	/**
 	 * Filter the image mime types that can be used for the <picture> element.
 	 *
-	 * Default is: ['image/avif', 'image/webp']. Returning an empty array will skip using the `picture` element.
+	 * Default is: ['image/avif', 'image/webp', 'image/jpeg', 'image/png]. Returning an empty array will skip using the `picture` element.
 	 *
 	 * The mime types will output in the picture element in the order they are provided.
 	 * The original image will be used as the fallback image for browsers that don't support the picture element.

plugins/webp-uploads/readme.txt

@@ -13,7 +13,7 @@ Converts images to more modern formats such as WebP or AVIF during upload.
 
 This plugin adds WebP and AVIF support for media uploads within the WordPress application. By default, AVIF images will be generated if supported on the hosting server, otherwise WebP will be used as the output format. When both formats are available, the output format can be selected under `Settings > Media`. Modern images will be generated only for new uploads, pre-existing images will only converted to a modern format if images are regenerated. Images can be regenerated with a plugin like [Regenerate Thumbnails](https://wordpress.org/plugins/regenerate-thumbnails/) or via WP-CLI with the `wp media regenerate` [command](https://developer.wordpress.org/cli/commands/media/regenerate/).
 
-By default, only modern image format sub-sizes will be generated for JPEG uploads - only the original uploaded file will still exist as a JPEG image, generated image sizes use be WebP or AVIF files. To change this behavior, there is a checkbox in `Settings > Media` "Also output JPEG" that - when checked - will result in the plugin generating both JPEG and WebP or AVIF images for every sub-size (noting again that this will only affect newly uploaded images, i.e. after making said change).
+By default, only modern image format sub-sizes will be generated for JPEG or PNG uploads - only the original uploaded file will still exist as a JPEG/PNG image, generated image sizes will be WebP or AVIF files. To change this behavior, there is a checkbox in `Settings > Media` "Output fallback images" that - when checked - will result in the plugin generating both the original format as well as WebP or AVIF images for every sub-size (noting again that this will only affect newly uploaded images, i.e. after making said change).
 
 _This plugin was formerly known as WebP Uploads._
 

plugins/webp-uploads/settings.php

@@ -86,10 +86,10 @@ function webp_uploads_add_media_settings_fields(): void {
 		return;
 	}
 
-	// Add JPEG Output settings field.
+	// Add fallback image output settings field.
 	add_settings_field(
 		'perflab_generate_webp_and_jpeg',
-		__( 'Also output JPEG', 'webp-uploads' ),
+		__( 'Output fallback images', 'webp-uploads' ),
 		'webp_uploads_generate_webp_jpeg_setting_callback',
 		'media',
 		'perflab_modern_image_format_settings',
@@ -145,7 +145,7 @@ function webp_uploads_generate_avif_webp_setting_callback(): void {
 	<label for="perflab_modern_image_format">
 		<?php esc_html_e( 'Generate images in this format', 'webp-uploads' ); ?>
 	</label>
-	<p class="description" id="perflab_modern_image_format_description"><?php esc_html_e( 'Select the format to use when generating new images from uploaded JPEGs.', 'webp-uploads' ); ?></p>
+	<p class="description" id="perflab_modern_image_format_description"><?php esc_html_e( 'Select the format to use when generating new images from uploaded images.', 'webp-uploads' ); ?></p>
 	<?php if ( ! $avif_supported ) : ?>
 		<br />
 		<div class="notice notice-warning inline">
@@ -172,9 +172,9 @@ function webp_uploads_generate_webp_jpeg_setting_callback(): void {
 	?>
 		<label for="perflab_generate_webp_and_jpeg">
 			<input name="perflab_generate_webp_and_jpeg" type="checkbox" id="perflab_generate_webp_and_jpeg" aria-describedby="perflab_generate_webp_and_jpeg_description" value="1"<?php checked( '1', get_option( 'perflab_generate_webp_and_jpeg' ) ); ?> />
-			<?php esc_html_e( 'Output JPEG images in addition to the modern format', 'webp-uploads' ); ?>
+			<?php esc_html_e( 'Also generate fallback images in the original upload format', 'webp-uploads' ); ?>
 		</label>
-		<p class="description" id="perflab_generate_webp_and_jpeg_description"><?php esc_html_e( 'Enabling JPEG output can improve compatibility, but will increase the filesystem storage use of your images.', 'webp-uploads' ); ?></p>
+		<p class="description" id="perflab_generate_webp_and_jpeg_description"><?php esc_html_e( 'Enabling fallback image output can improve compatibility, but will increase the filesystem storage use of your images.', 'webp-uploads' ); ?></p>
 	<?php
 }
 
@@ -196,7 +196,7 @@ function webp_uploads_use_picture_element_callback(): void {
 		}
 	</style>
 	<div id="webp_uploads_picture_element_notice" class="notice notice-info inline" <?php echo $jpeg_fallback_enabled ? 'hidden' : ''; ?>>
-		<p><?php esc_html_e( 'This setting requires JPEG also be output as a fallback option.', 'webp-uploads' ); ?></p>
+		<p><?php esc_html_e( 'This setting requires fallback image output to be enabled.', 'webp-uploads' ); ?></p>
 	</div>
 	<div id="webp_uploads_picture_element_fieldset" class="<?php echo ! $jpeg_fallback_enabled ? 'disabled' : ''; ?>">
 		<label for="webp_uploads_use_picture_element" id="webp_uploads_use_picture_element_label">
@@ -228,9 +228,9 @@ function webp_uploads_use_picture_element_callback(): void {
 			?>
 			<em><?php esc_html_e( '(experimental)', 'webp-uploads' ); ?></em>
 		</label>
-		<p class="description" id="webp_uploads_use_picture_element_description"><?php esc_html_e( 'The picture element serves a modern image format with a fallback to JPEG. Warning: Make sure you test your theme and plugins for compatibility. In particular, CSS selectors will not match images when using the child combinator (e.g. figure > img).', 'webp-uploads' ); ?></p>
+		<p class="description" id="webp_uploads_use_picture_element_description"><?php esc_html_e( 'The picture element serves a modern image format with a fallback to the original upload format. Warning: Make sure you test your theme and plugins for compatibility. In particular, CSS selectors will not match images when using the child combinator (e.g. figure > img).', 'webp-uploads' ); ?></p>
 		<div id="webp_uploads_jpeg_fallback_notice" class="notice notice-info inline" <?php echo $picture_element_option ? '' : 'hidden'; ?>>
-			<p><?php esc_html_e( 'Picture elements will only be used when JPEG fallback images are available. So this will not apply to any images you may have uploaded while the "Also generate JPEG" setting was disabled.', 'webp-uploads' ); ?></p>
+			<p><?php esc_html_e( 'Picture elements will only be used when fallback images are available. So this will only apply to  images you have uploaded while the "Also generate fallback images" setting was enabled.', 'webp-uploads' ); ?></p>
 		</div>
 	</div>
 	<script>
@@ -239,7 +239,7 @@ function webp_uploads_use_picture_element_callback(): void {
 			document.getElementById( 'webp_uploads_jpeg_fallback_notice' ).hidden = ! this.checked;
 		} );
 
-		// Listen for clicks on the JPEG output checkbox, enabling/disabling the
+		// Listen for clicks on the fallback output checkbox, enabling/disabling the
 		// picture element checkbox accordingly.
 		document.getElementById( 'perflab_generate_webp_and_jpeg' ).addEventListener( 'change', function () {
 			document.querySelector( '.webp-uploads-use-picture-element' ).classList.toggle( 'webp-uploads-disabled', ! this.checked );

plugins/webp-uploads/tests/test-helper.php

@@ -367,12 +367,14 @@ public function test_it_should_return_default_transforms_when_filter_returns_non
 				'image/jpeg' => array( 'image/avif' ),
 				'image/webp' => array( 'image/webp' ),
 				'image/avif' => array( 'image/avif' ),
+				'image/png'  => array( 'image/avif' ),
 			);
 		} else {
 			$default_transforms = array(
 				'image/jpeg' => array( 'image/webp' ),
 				'image/webp' => array( 'image/webp' ),
 				'image/avif' => array( 'image/avif' ),
+				'image/png'  => array( 'image/webp' ),
 			);
 		}
 
@@ -431,6 +433,7 @@ public function test_it_should_return_jpeg_and_webp_transforms_when_option_gener
 			$this->assertSame(
 				array(
 					'image/jpeg' => array( 'image/jpeg', 'image/avif' ),
+					'image/png'  => array( 'image/png', 'image/avif' ),
 					'image/avif' => array( 'image/avif', 'image/jpeg' ),
 				),
 				$transforms
@@ -439,6 +442,7 @@ public function test_it_should_return_jpeg_and_webp_transforms_when_option_gener
 			$this->assertSame(
 				array(
 					'image/jpeg' => array( 'image/jpeg', 'image/webp' ),
+					'image/png'  => array( 'image/png', 'image/webp' ),
 					'image/webp' => array( 'image/webp', 'image/jpeg' ),
 				),
 				$transforms