如何使用wordpress timthumb替代方案获取wordpress特色图像URL

我正在尝试通过此函数传递wp_get_attachment_image_src调用

<?php 
           $url = wp_get_attachment_image_src( get_post_thumbnail_id( $post->ID ), 'single-post-thumbnail' );      // Required
$width = 300;                                                                  // Optional. Defaults to '150'
$height = 200;                                                                 // Optional. Defaults to '150'
$crop = true;                                                                  // Optional. Defaults to 'true'
$retina = false;                                                               // Optional. Defaults to 'false'
// Call the resizing function (returns an array)
$image = matthewruddy_image_resize( $url, $width, $height, $crop, $retina );
// Outputs resized image URL, http://yourwordpressdomain.com/wp-content/uploads/01/image1-300x200.png
echo $image['url']; ?>

输出不会呈现图像 url，而是呈现

<img src=" Array">

请帮忙！我还尝试基于此代码创建一个wordpress函数，但也没有运气：

function tuts_custom_img( $thumb_size, $image_width, $image_height ) {
  global $post;
  $params = array( 'width' => $image_width, 'height' => $image_height );
  $url = wp_get_attachment_image_src( get_post_thumbnail_id( $post->ID, '' ), $thumb_size );
  $custom_img_src = matthewruddy_image_resize( $url[0], $params );
  return $custom_img_src;
}