<p>This plugin will scan your thumbnail-less posts and look for a suitable image to use as a thumbnail.<br />
It will look for images linked in the post content and will download and add them to the local library.<br />
Post scanning is performed only when <code>the_post_thumbnail</code> or <code>get_the_post_thumbnail</code> are called for<br />
that particular post.</p>
<p>So you designed your new thumbnail-based template, but you have tons of thumbnail-less posts and<br />
don’t want to spend too much time on scraping your old posts for a thumbnail picture. Maybe you<br />
think you will probably forget to set a thumbnail for your new posts. Maybe both, as was my case :).</p>
<p>When a thumbnail for a post is queried and nothing is found this plugin will scrape the post for<br />
an <code><img></code> tag and its <code>href</code> property. Once a suitabile image is found (based on the configured<br />
settings), it will be downloaded ad set as the post thumbnail. If no suitable image is found,<br />
a default one will be used.</p>
<p>This plugin is still in early development state. It just covers my needs (see the “To do” section<br />
for more details). It has been tested only with wordpress 3.0.1, but should work also with 2.9,<br />
since I used similar code with 2.9 (even if it was included in my template’s <code>functions.php</code>).</p>
<p>The plugin is not supported. This doesn’t mean that I will not look into submitted bugs. Anyway,<br />
don’t expect prompt answers, since this is done in my spare time.</p>
<h3>To do</h3>
<p>Many things should be done in future releases. Here are some:</p>
<ul>
<li>Current version always downloads selected linked images. This works good with images hosted on external sites.<br />
If your posts link to images hosted in your media library, you will end up with two images.</li>
<li>A more user friendly name should be used for images added to the library (e.g. Thumbnail for post …)</li>
<li>Somewhere, a button to reset the “previously scanned” status of all posts should be provided (on current version,<br />
you cas set or reset it for single posts in the edit page.</li>
<li>“previously scanned” status should probably be reset (or at least you should be asked to) when publishing a<br />
updating an existing post</li>
</ul>
<p>More ideas are wellcome.</p>


Automatic Thumbnail Generator

Automated on-demand generation of posts thumbnails.

Grégory Viguier

<p>This plugin is meant for developers, it allows to attach a thumbnail to taxonomy terms.</p>
<h4>UI for setting the thumbnails</h4>
<p>The thumbnail can be added on term creation or later on the term edition page.<br />
The terms list has a column displaying the current thumbnail (so far, no specific action here).<br />
The plugin uses the “new” media window (the one used since WP 3.5), not the old thickbox.<br />
I made some extra efforts to enhance accessibility. I’m not an a11y expert but the UI is not only a “Add thumbnail” button. For instance, the new <code>wp.a11y.speak()</code> is used when available. Please give me feedback if you think it can be improved.<br />
Works with or without JavaScript.<br />
If JavaScript is enabled, thumbnails are set via ajax in the term edition window, no need to update the term.<br />
By default, the UI is displayed for all public taxonomies, but this can be filtered that way:</p>
<pre><code>add_filter( 'sftth_taxonomies', 'my_taxonomies_with_thumbnail' );

function my_taxonomies_with_thumbnail( $taxonomies ) {
    unset( $taxonomies['post_tag'] );
    $taxonomies['my_custom_tax'] = 'my_custom_tax';
    return $taxonomies;
}
</code></pre>
<h4>Template tags</h4>
<p>Find them in <code>inc/template-tags.php</code>.<br />
<strong>Important note: for WP 4.4+, these functions use <code>term_id</code>. For WP < 4.4, they use <code>term_taxonomy_id</code>.</strong><br />
I tried to mimic the post thumbnail functions:</p>
<ol>
<li><code>get_term_thumbnail_id( $term_id )</code>: Retrieve term thumbnail ID.</li>
<li><code>has_term_thumbnail( $term_id )</code>: Check if a term has a thumbnail attached to it.</li>
<li><code>the_term_thumbnail( $term_id, $size = 'post-thumbnail', $attr = '' )</code>: Display the term thumbnail.</li>
<li><code>get_term_thumbnail( $term_id, $size = 'post-thumbnail', $attr = '' )</code>: Retrieve the term thumbnail.</li>
<li><code>set_term_thumbnail( $term_id, $thumbnail_id )</code>: Set a term thumbnail.</li>
<li><code>delete_term_thumbnail( $term_id )</code>: Detach a thumbnail from a term.</li>
</ol>
<h4>Store the data</h4>
<p>From WordPress 4.4, the term metas API is used.<br />
Below WordPress 4.4, there are two ways to store the thumbnail IDs:</p>
<ol>
<li>Use term metas with the plugin <a href="https://wordpress.org/plugins/meta-for-taxonomies/" rel="ugc">Meta for Taxonomies</a>.</li>
<li>Use an option (an array association of <code>term_taxonomy_id</code> => <code>thumbnail_id</code> integers). The option name can be customized by defining the constant <code>SFTTH_OPTION_NAME</code> in <code>wp-config.php</code>.</li>
</ol>
<h4>Get terms</h4>
<p>Use <code>get_terms()</code> with a specific parameter to retrieve only terms with a thumbnail:</p>
<pre><code>$terms = get_terms( array(
    'with_thumbnail' => true,
) );
</code></pre>
<p>From WordPress 4.4, you can also use a small helper to build your meta query:</p>
<pre><code>$terms = get_terms( array(
    'meta_query' => array(
        'relation' => 'AND',
        array(
            // Any meta query.
        ),
        sftth_meta_query(),
    ),
) );
</code></pre>
<p>Below WordPress 4.4, if you use the plugin <em>Meta for Taxonomies</em>, you should always cache thumbnails.<br />
When using <code>'with_thumbnail' => false</code> you will retrieve all terms, even those without a thumbnail, but the thumbnails will be cached, saving calls to the database later:</p>
<pre><code>$terms = get_terms( array(
    'with_thumbnail' => false,
) );
</code></pre>
<h4>Uninstall</h4>
<p>When uninstalling the plugin, you can decide to not delete the thumbnails, simply define a constant in <code>wp-config.php</code>:</p>
<pre><code>define( 'SFTTH_KEEP_DATA', true );
</code></pre>
<h4>Translations</h4>
<ul>
<li>US English</li>
<li>French</li>
</ul>
<h4>Requirements</h4>
<p>Should work starting from WP 3.5, but tested only in WP 4.2.2+ so far.</p>
<h4>Credits</h4>
<p>Photo used for the banner by <a href="https://www.flickr.com/photos/n1colas/2598073727/" rel="nofollow ugc">Nicolas Janik</a> (<a href="https://creativecommons.org/licenses/by/2.0/" rel="nofollow ugc">CC BY 2.0</a>).</p>


Taxonomy Thumbnail

Does the work well

So easy to use, writing this review takes longer than using and understanding the plugin.
*****

Automatic Thumbnail Generator vs Taxonomy Thumbnail