Wordpress替换图像的默认宽度和高度值

I want to replace the default width and height values that are added by the visual editor in Wordpress.

I am using the add_filter function:

add_filter( 'post_thumbnail_html', 'remove_width_attribute', 10 );
add_filter( 'image_send_to_editor', 'remove_width_attribute', 10 );

and my function is:

function remove_width_attribute( $html ) {
  $html = preg_replace( '/\s*(?:(?:width=|height=)"(\d*)")/', 'style="max-width: ${1}px; max-height: ${2}px;"', $html );    
  return $html;
}

Input string is:

<img src="path/to/image.png" alt="" width="300" height="71" class="random-class pull-left" />

May also contain a tags wrapped around.

I want the output to be:

<img ..... style="max-width: 300px; max-height: 71px;">

Instead of using alternation, just match the width then height and capture the digits.

$html = preg_replace('/width="(\d+)"\s*height="(\d+)"/', 'style="max-width: $1px; max-height: $2px;"', $html);