How to always add caption element to images - even if empty?

Question

I want to add the caption ALWAYS to images, even if it is empty. This is my function to add the caption, but the caption element will not be generated when there is no content in it, how to add the caption element always?

add_filter('img_caption_shortcode', 'caption_shortcode_inline_text', 10, 3);
function caption_shortcode_inline_text($empty, $attr, $content) {
extract(shortcode_atts(array(
    'id'    => '',
    'align' => 'alignnone',
    'width' => '',
    'caption' => ''
), $attr));

// in this part I amtrying to always add the caption element but it doesn't work:

if (1 < (int) $width || 1 > (int) $width || $caption || !$caption)
    return '<div ' . $id . 'class="wp-caption ' . esc_attr($align) . '" style="width: ' . (10 + (int) $width) . 'px">'
    . do_shortcode($content) . '<p class="wp-caption-text">' . $caption . '</p></div>';
}

Answer 1

This works:

add_filter( 'disable_captions', create_function('$a', 'return true;') );
function image_send_to_editor_2($html, $id, $caption, $title, $align, $url, $size, $alt) {

    $width = 'auto';

    if ( preg_match( '/width="([0-9]+)/', $html, $matches ) ) {
        $width = $matches[1] . 'px';
    }

    $output = '<div id="attachment-' . $id . '" class="wp-caption align' . $align . '" style="width: ' . $width . ';">';
    $output .= $html;
    $output .= '<p class="wp-caption-text">' . $caption . '</p>';
    $output .= '</div>';
    return $output;

}

add_filter('image_send_to_editor', 'image_send_to_editor_2', 10, 8);