diff --git a/tests/phpunit/tests/http/functions.php b/tests/phpunit/tests/http/functions.php
index 9a2b1ba172..79e0727460 100644
--- a/tests/phpunit/tests/http/functions.php
+++ b/tests/phpunit/tests/http/functions.php
@@ -3,10 +3,15 @@
 /**
  * @group http
  * @group external-http
- *
- * @requires extension openssl
  */
 class Tests_HTTP_Functions extends WP_UnitTestCase {
+	public function setUp() {
+		if ( ! extension_loaded( 'openssl' ) ) {
+			$this->markTestSkipped( 'Tests_HTTP_Functions requires openssl.' );
+		}
+
+		parent::setUp();
+	}
 
 	function test_head_request() {
 		// this url give a direct 200 response
diff --git a/tests/phpunit/tests/image/functions.php b/tests/phpunit/tests/image/functions.php
index 0f2ae01e1c..9cc3f09d2a 100644
--- a/tests/phpunit/tests/image/functions.php
+++ b/tests/phpunit/tests/image/functions.php
@@ -108,10 +108,12 @@ class Tests_Image_Functions extends WP_UnitTestCase {
 	/**
 	 * Test save image file and mime_types
 	 * @ticket 6821
-	 *
-	 * @requires extension fileinfo
 	 */
 	public function test_wp_save_image_file() {
+		if ( ! extension_loaded( 'fileinfo' ) ) {
+			$this->markTestSkipped( 'The fileinfo PHP extension is not loaded.' );
+		}
+
 		include_once( ABSPATH . 'wp-admin/includes/image-edit.php' );
 
 		// Mime types
@@ -158,10 +160,12 @@ class Tests_Image_Functions extends WP_UnitTestCase {
 	/**
 	 * Test that a passed mime type overrides the extension in the filename
 	 * @ticket 6821
-	 *
-	 * @requires extension fileinfo
 	 */
 	public function test_mime_overrides_filename() {
+		if ( ! extension_loaded( 'fileinfo' ) ) {
+			$this->markTestSkipped( 'The fileinfo PHP extension is not loaded.' );
+		}
+
 		// Test each image editor engine
 		$classes = array('WP_Image_Editor_GD', 'WP_Image_Editor_Imagick');
 		foreach ( $classes as $class ) {
@@ -194,10 +198,12 @@ class Tests_Image_Functions extends WP_UnitTestCase {
 	/**
 	 * Test that mime types are correctly inferred from file extensions
 	 * @ticket 6821
-	 *
-	 * @requires extension fileinfo
 	 */
 	public function test_inferred_mime_types() {
+		if ( ! extension_loaded( 'fileinfo' ) ) {
+			$this->markTestSkipped( 'The fileinfo PHP extension is not loaded.' );
+		}
+
 		// Mime types
 		$mime_types = array(
 			'jpg'  => 'image/jpeg',
@@ -290,11 +296,14 @@ class Tests_Image_Functions extends WP_UnitTestCase {
 		unlink( $file );
 	}
 
-	/**
-	 * @requires extension openssl
-	 * @requires function imagejpeg
-	 */
 	public function test_wp_crop_image_url() {
+		if ( !function_exists( 'imagejpeg' ) )
+			$this->markTestSkipped( 'jpeg support unavailable' );
+
+		if ( ! extension_loaded( 'openssl' ) ) {
+			$this->markTestSkipped( 'Tests_Image_Functions::test_wp_crop_image_url() requires openssl.' );
+		}
+
 		$file = wp_crop_image( 'https://asdftestblog1.files.wordpress.com/2008/04/canola.jpg',
 							  0, 0, 100, 100, 100, 100, false,
 							  DIR_TESTDATA . '/images/' . rand_str() . '.jpg' );
@@ -314,10 +323,11 @@ class Tests_Image_Functions extends WP_UnitTestCase {
 		$this->assertInstanceOf( 'WP_Error', $file );
 	}
 
-	/**
-	 * @requires extension openssl
-	 */
 	public function test_wp_crop_image_url_not_exist() {
+		if ( ! extension_loaded( 'openssl' ) ) {
+			$this->markTestSkipped( 'Tests_Image_Functions::test_wp_crop_image_url_not_exist() requires openssl.' );
+		}
+
 		$file = wp_crop_image( 'https://asdftestblog1.files.wordpress.com/2008/04/canoladoesnotexist.jpg',
 							  0, 0, 100, 100, 100, 100 );
 		$this->assertInstanceOf( 'WP_Error', $file );
diff --git a/tests/phpunit/tests/image/meta.php b/tests/phpunit/tests/image/meta.php
index a29c4a3e35..30613d48a8 100644
--- a/tests/phpunit/tests/image/meta.php
+++ b/tests/phpunit/tests/image/meta.php
@@ -4,11 +4,17 @@
  * @group image
  * @group media
  * @group upload
- *
- * @requires extension gd
- * @requires extension exif
  */
 class Tests_Image_Meta extends WP_UnitTestCase {
+	function setUp() {
+		if ( ! extension_loaded( 'gd' ) )
+			$this->markTestSkipped( 'The gd PHP extension is not loaded.' );
+		if ( ! extension_loaded( 'exif' ) )
+			$this->markTestSkipped( 'The exif PHP extension is not loaded.' );
+		if ( ! is_callable( 'wp_read_image_metadata' ) )
+			$this->markTestSkipped( 'wp_read_image_metadata() is not callable.' );
+		parent::setUp();
+	}
 
 	function test_exif_d70() {
 		// exif from a Nikon D70