Using wp_read_audio_metadata()

Question

I am trying to get some metadata from an mp3 file in WordPress. Specifically the length variable. Here is a bit of my code. It's not shown here but I have included the wp-admin/includes/media.php file. When I look at my page http://beta.openskyministry.org/podcasts/ I just see empty tags for <itunes:length></itunes:length>

Let me know If you need anything else to help answer my question.

$aud_meta = wp_read_audio_metadata($aud_url); ?>

    <item>


        <title><?php the_title(); ?></title>

        <itunes:author><?php echo htmlspecialchars((get_bloginfo('name'))); ?></itunes:author>

        <itunes:summary><?php echo  htmlspecialchars(strip_tags(get_the_excerpt())); ?></itunes:summary> 

        <itunes:length><?php echo $aud_meta['length_formatted']; ?></itunes:length>

Answer 1

WordPress already stores media metadata, so there's no need to go over it. Solution is as simple as:

add_action( 'wp_head', function(){
    global $post;
    if ( is_single($post) ) {
        $args = array( 
            'post_type'     => 'attachment',
            'numberposts'   => 1,
            'post_parent'   => $post->ID,
            'post_mime_type' => 'audio'
        );  
        $attachments = get_posts( $args );
        if($attachments){
            $meta = wp_get_attachment_metadata( $attachments[0]->ID );
            echo "<itunes:length>{$meta['length_formatted']}</itunes:length>";
        }           
    }
});

For the records, wp_read_audio_metadata() expects the file path, not the URL. If needed, it should be:

$path = get_attached_file( $attachment->ID );
$meta = wp_read_audio_metadata($path);
echo "<itunes:length>{$meta['length_formatted']}</itunes:length>";

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