Change WP Image editor quality for mime types

modules/images/webp-uploads/load.php

@@ -742,3 +742,33 @@ function webp_uploads_get_image_sizes_additional_mime_type_support() {
 
 	return $allowed_sizes;
 }
+
+/**
+ * Updates the quality of images used in the wp editor.
+ * For WP version less than 6.2 returns 82,
+ * Otherwise returns default quality.
+ *
+ * @since n.e.x.t
+ *
+ * @param int    $quality   Quality level between 1 (low) and 100 (high).
+ * @param string $mime_type Image mime type.
+ * @return int The updated quality for mime types.
+ */
+function webp_uploads_set_wp_image_editor_quality( $quality, $mime_type ) {
+	global $wp_version;
+
+	$valid_mime_transforms = webp_uploads_get_upload_image_mime_transforms();
+
+	// Return early for non image or invalid mime types.
+	if ( ! isset( $valid_mime_transforms[ $mime_type ] ) ) {
+		return $quality;
+	}
+
+	if ( version_compare( '6.2', $wp_version, '>=' ) ) {
+		return $quality;
+	}
+
+	// Default quality set to 82 for all mimes for WP version less than 6.2.
+	return 82;
+}
+add_filter( 'wp_editor_set_quality', 'webp_uploads_set_wp_image_editor_quality', 10, 2 );

tests/modules/images/webp-uploads/load-tests.php

@@ -775,6 +775,7 @@ public function it_should_create_webp_for_full_size_which_is_smaller_in_webp_for
 		$this->opt_in_to_jpeg_and_webp();
 
 		add_filter( 'webp_uploads_discard_larger_generated_images', '__return_true' );
+		remove_all_filters( 'wp_editor_set_quality' );
 
 		// Look for an image that contains only full size mime type images.
 		$attachment_id = self::factory()->attachment->create_upload_object( TESTS_PLUGIN_DIR . '/tests/testdata/modules/images/leafs.jpg' );
@@ -801,6 +802,7 @@ public function it_should_create_webp_for_some_sizes_which_are_smaller_in_webp_f
 		$this->opt_in_to_jpeg_and_webp();
 
 		add_filter( 'webp_uploads_discard_larger_generated_images', '__return_true' );
+		remove_all_filters( 'wp_editor_set_quality' );
 
 		// Look for an image that contains all of the additional mime type images.
 		$attachment_id = self::factory()->attachment->create_upload_object( TESTS_PLUGIN_DIR . '/tests/testdata/modules/images/balloons.webp' );
@@ -918,11 +920,63 @@ public function it_should_create_mime_types_for_allowed_sizes_only_via_global_va
 		$this->assertImageNotHasSizeSource( $attachment_id, 'not_allowed_size_200x150', 'image/webp' );
 	}
 
+	/**
+	 * Test image quality for image conversion.
+	 *
+	 * @test
+	 */
+	public function test_set_quality_with_image_conversion() {
+		global $wp_version;
+		// Set conversions for uploaded images.
+		add_filter( 'image_editor_output_format', array( $this, 'image_editor_output_formats' ) );
+		$expected_webp = 82;
+		if ( version_compare( '6.2', $wp_version ) ) {
+			$expected_webp = 86;
+		}
+
+		$editor = wp_get_image_editor( TESTS_PLUGIN_DIR . '/tests/testdata/modules/images/dice.png', array( 'mime_type' => 'image/png' ) );
+
+		// Quality setting for the source image. For PNG the fallback default of 82 is used.
+		$this->assertSame( 82, $editor->get_quality(), 'Default quality setting for PNG is 82.' );
+
+		// A PNG image will be converted to WEBP whose quality should be 82 for wp version 6.2 and above.
+		$editor->save();
+		$this->assertSame( $expected_webp, $editor->get_quality(), 'Output image format is WEBP. Quality setting for it should be 82 for WP version 6.2 and above.' );
+
+		unset( $editor );
+
+		$editor = wp_get_image_editor( TESTS_PLUGIN_DIR . '/tests/testdata/modules/images/leafs.jpg' );
+
+		// Quality setting for the source image. For JPG the fallback default of 82 is used.
+		$this->assertSame( 82, $editor->get_quality(), 'Default quality setting for JPG is 82.' );
+
+		// A JPG image will be converted to WEBP whose quality should be 82 for wp version 6.2 and above.
+		$editor->save();
+		$this->assertSame( $expected_webp, $editor->get_quality(), 'Output image format is WEBP. Quality setting for it should be 82 for WP version 6.2 and above.' );
+
+		unset( $editor );
+		remove_filter( 'image_editor_output_format', array( $this, 'image_editor_output_formats' ) );
+	}
+
 	/**
 	 * Runs (empty) hooks to satisfy webp_uploads_in_frontend_body() conditions.
 	 */
 	private function mock_frontend_body_hooks() {
 		remove_all_actions( 'template_redirect' );
 		do_action( 'template_redirect' );
 	}
+
+	/**
+	 * Changes the output format when editing images. PNG and JPEG files
+	 * will be converted to WEBP (if the image editor in PHP supports it).
+	 *
+	 * @param array $formats Output formats.
+	 *
+	 * @return array
+	 */
+	public function image_editor_output_formats( $formats ) {
+		$formats['image/png']  = 'image/webp';
+		$formats['image/jpeg'] = 'image/webp';
+		return $formats;
+	}
 }

tests/utils/TestCase/DominantColorTestCase.php

@@ -24,7 +24,7 @@ public function provider_get_dominant_color() {
 			),
 			'green_jpg'     => array(
 				'image_path'            => TESTS_PLUGIN_DIR . '/tests/testdata/modules/images/dominant-color/green.jpg',
-				'expected_color'        => array( '00ff00', '00ff01' ),
+				'expected_color'        => array( '00ff00', '00ff01', '02ff01' ),
 				'expected_transparency' => false,
 			),
 			'white_jpg'     => array(