diff --git a/src/wp-includes/media.php b/src/wp-includes/media.php
index a5642608fb..6150b99b82 100644
--- a/src/wp-includes/media.php
+++ b/src/wp-includes/media.php
@@ -503,8 +503,9 @@ function image_resize_dimensions($orig_w, $orig_h, $dest_w, $dest_h, $crop = fal
 	}
 
 	// if the resulting image would be the same size or larger we don't want to resize it
-	if ( $new_w >= $orig_w && $new_h >= $orig_h )
+	if ( $new_w >= $orig_w && $new_h >= $orig_h && $dest_w != $orig_w && $dest_h != $orig_h ) {
 		return false;
+	}
 
 	// the return array matches the parameters to imagecopyresampled()
 	// int dst_x, int dst_y, int src_x, int src_y, int dst_w, int dst_h, int src_w, int src_h
diff --git a/tests/phpunit/tests/image/dimensions.php b/tests/phpunit/tests/image/dimensions.php
index 20f2cf4626..79a7f0e575 100644
--- a/tests/phpunit/tests/image/dimensions.php
+++ b/tests/phpunit/tests/image/dimensions.php
@@ -128,6 +128,18 @@ class Tests_Image_Dimensions extends WP_UnitTestCase {
 		$this->assertEquals( array(0, 0, 0, 20, 400, 500, 480, 600), $out );
 	}
 
+	function test_640x480() {
+		// crop 640x480 to fit 640x480 (no change)
+		$out = image_resize_dimensions(640, 480, 640, 480, true);
+		// dst_x, dst_y, src_x, src_y, dst_w, dst_h, src_w, src_h
+		$this->assertEquals( array(0, 0, 0, 0, 640, 480, 640, 480), $out );
+
+		// resize 640x480 to fit 640x480 (no change)
+		$out = image_resize_dimensions(640, 480, 640, 480, false);
+		// dst_x, dst_y, src_x, src_y, dst_w, dst_h, src_w, src_h
+		$this->assertEquals( array(0, 0, 0, 0, 640, 480, 640, 480), $out );
+	}
+
 	/**
 	 * @ticket 19393
 	 */