How to add a credit line to a photo caption

Question

How to add a credit line to a photo caption

Sean Henderson

2013年10月23日 21:25

I'm trying to find a way to automatically add a photographer credit line to user-inserted photos. I've added custom fields to the media uploader for 'Photographer Name' and 'Photographer URL' but I can't figure out a way to automatically insert the input from these fields into the caption field so that they will automatically display with the photo.

Here's the code to generate the custom fields:

function attachment_field_credit( $form_fields, $post ) {
$form_fields['photographer-name'] = array(
    'label' = 'Photographer Name',
    'input' = 'text',
    'value' = get_post_meta( $post-ID, 'photographer_name', true ),
    'helps' = 'If provided, photo credit will be displayed',
);

$form_fields['photographer-url'] = array(
    'label' = 'Photographer URL',
    'input' = 'text',
    'value' = get_post_meta( $post-ID, 'photographer_url', true ),
    'helps' = 'Add Photographer URL',
);  

return $form_fields;
}

add_filter( 'attachment_fields_to_edit', 'be_attachment_field_credit', 10, 2 );

Thanks for your help.

Topic captions linking images Wordpress

Category Web

mrwweb · Accepted Answer · 2013年10月23日 21:25

I tried to do this once and almost got almost. Here's what I did learn. Depending on your needs, this solution may be workable.

You can append content to media when it's inserted into the editor using the get_image_tag filter:

/**
 * Filter to get caption and append image information to it.
 *
 * @return text HTML content describing with media attribution
 **/

add_filter('get_image_tag', 'my_append_media_credit', 20, 2);

function my_append_media_credit( $html, $id ) {

    $my_media_string = /* get your fields and put them together nicely */;

    $html = $html . $my_media_string;

    return $html;

}

However, you'll notice that I mentioned it only works for images when they're inserted into posts (and possibly updated, though I'd need to check out that). So if you're starting a site from scratch, that may get you far enough, but I got stuck on retroactively applying it to existing images in posts.

You could get some additional coverage for images with captions by filtering img_caption_shortcode which filters the [caption] shortcode output but that still leaves images without captions and already in posts uncovered.

UPDATE 10/23/13 2:20pm PST:

Here's the function I used to generate the $my_media_string in the code above:

/**
 * Function to lookup media creator fields and put them together.
 *
 * returns an html string with creator name and license name links.
 **/

function my_media_credit_string( $my_media_id ) {

    $my_name = get_post_meta( $my_media_id, 'my_creator_name', true );
    $my_name_url = get_post_meta( $my_media_id, 'my_creator_url', true );

    $my_creator = null;
    if( $my_name ) {
        if( $my_name_url ) {
            $my_creator = ' <a href="' . $my_name_url . '">' . $my_name . '</a>.';  
        } else {
            $my_creator = ' ' . $my_name;
        }
    }

    return '<span class="my-media-attr">Credit:' . $my_creator . '</span>';

}

So the first snippet would get this:

    $my_media_string = $my_media_credit_string( $id );

How to add a credit line to a photo caption

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