Auto Featured Image

Must update change .php file to and then regenerate thumbnails in settings area. Make sure that settings>media>thumbnail size and uncheck exact to remain in proportion.

You may need to download the regenerate thumbnail widget as well:

<?php
/*
* Plugin Name: Auto Featured Image
* Description: Automatically generate featured image for new/old posts if Post Thumbnail is not set manually. In addition to post attachment, it also support external image, Youtube, Vimeo, DailyMotion. Originally designed by Aditya Mooley <adityamooley@sanisoft.com>.
* Version: 1.2
* Author: Ka Yue Yeung <kayuey@gmail.com>
* Author URI: http://ka-yue.com
*/

class Auto_Feautred_Image_Plugin {

public function __construct()
{
// run plugin every time people save post
add_action( ‘save_post’, array(__CLASS__, “generate_thumbmail”) );

// plugin should work for scheduled posts as well
add_action( ‘transition_post_status’, array(__CLASS__, “check_transition”) );

//
add_action( ‘admin_notices’, array(__CLASS__, “check_permission”) );

add_action( ‘admin_menu’, array(__CLASS__, “add_admin_menu”) ); // Add batch process capability
add_action( ‘wp_ajax_generatepostthumbnail’, array(__CLASS__, “ajax_process_post”) ); // Hook to implement AJAX request
}

/**
* Function to check whether scheduled post is being published. If so, afi_publish_post should be called.
*
* @param $new_status
* @param $old_status
* @param $post
* @return void
*/
static function check_transition( $new_status=”, $old_status=”, $post=” )
{
if (‘publish’ == $new_status && ‘future’ == $old_status) {
self::generate_thumbmail($post->ID);
}
}

/**
* Function to save first image in post as post thumbmail.
*/
static function generate_thumbmail( $post_id )
{
global $wpdb;

$post = get_post($dummy_wp = $post_id);

// reset post parent id
$post_parent_id = $post->post_parent === 0 ? $post->ID : $post->post_parent;

// check whether Post Thumbnail is already set for this post.
if ( has_post_thumbnail($post_parent_id) ) return “has thumbnail”;

// case 1: there is an image attachment we can use
// found all images attachments from the post
$attachments = array_values(get_children(array(
‘post_parent’ => $post_parent_id,
‘post_status’ => ‘inherit’,
‘post_type’ => ‘attachment’,
‘post_mime_type’ => ‘image’,
‘order’ => ‘ASC’,
‘orderby’ => ‘menu_order ID’)
));

// if attachment found, set the first attachment as thumbnail
if( sizeof($attachments) > 0 ) {
update_post_meta( $post_parent_id, ‘_thumbnail_id’, $attachments[0]->ID );
return;
}

// case 2: need to search for an image from content
// find image from content
// check is there any image we can use
$image_url = self::found_image_url($post->post_content);

// if no url found, do nothing
if( $image_url == null ) return;

// try to create an image attchment from given image url, and use it as thumbnail
$post_thumbnail_id = self::create_post_attachment_from_url($image_url);

// update post thumbnail meta if thumbnail found
if(is_int($post_thumbnail_id)) {
update_post_meta( $post_parent_id, ‘_thumbnail_id’, $post_thumbnail_id );
}

return;
}

/**
* @return Integer if attachment id if attachment is used.
* @return String if image url if external image is used.
* @return NULL if fail
*/
static function found_image_url($html)
{
$matches = array();

// images
$pattern = ‘/<img[^>]*src=\”?(?<src>[^\”]*)\”?[^>]*>/im’;
preg_match( $pattern, $html, $matches );
if($matches[‘src’]) {
return $matches[‘src’];
}

// youtube
$pattern = “/(http:\/\/www.youtube.com\/watch\?.*v=|http:\/\/www.youtube-nocookie.com\/.*v\/|http:\/\/www.youtube.com\/embed\/|http:\/\/www.youtube.com\/v\/)(?<id>[\w-_]+)/i”;
preg_match( $pattern, $html, $matches );
if( $matches[‘id’] ) {
return “http://img.youtube.com/vi/{$matches[‘id’]}/0.jpg”;
}

// vimeo
$pattern = “/(http:\/\/vimeo.com\/|http:\/\/player.vimeo.com\/video\/|http:\/\/vimeo.com\/moogaloop.swf?.*clip_id=)(?<id>[\d]+)/i”;
preg_match( $pattern, $html, $matches );
if( $vimeo_id = $matches[‘id’] ) {
$hash = unserialize(file_get_contents(“http://vimeo.com/api/v2/video/{$vimeo_id}.php”));
return “{$hash[0][‘thumbnail_medium’]}”;
}

// dailymotion
// http://www.dailymotion.com/thumbnail/150×150/video/xexakq
$pattern = “/(http:\/\/www.dailymotion.com\/swf\/video\/)(?<id>[\w\d]+)/i”;
preg_match( $pattern, $html, $matches );
if( $matches[‘id’] ) {
return “http://www.dailymotion.com/thumbnail/150×150/video/{$matches[‘id’]}.jpg”;
}

return null;
}

/**
* Function to fetch the image from URL and generate the required thumbnails
* @return Attachment ID
*/
static function create_post_attachment_from_url($imageUrl = null)
{
if(is_null($imageUrl)) return null;

// get file name
$filename = substr($imageUrl, (strrpos($imageUrl, ‘/’))+1);
if (!(($uploads = wp_upload_dir(current_time(‘mysql’)) ) && false === $uploads[‘error’])) {
return null;
}

// Generate unique file name
$filename = wp_unique_filename( $uploads[‘path’], $filename );

// move the file to the uploads dir
$new_file = $uploads[‘path’] . “/$filename”;

// download file
if (!ini_get(‘allow_url_fopen’)) {
$file_data = self::curl_get_file_contents($imageUrl);
} else {
$file_data = @file_get_contents($imageUrl);
}

// fail to download image.
if (!$file_data) {
return null;
}

file_put_contents($new_file, $file_data);

// Set correct file permissions
$stat = stat( dirname( $new_file ));
$perms = $stat[‘mode’] & 0000666;
@chmod( $new_file, $perms );

// get the file type. Must to use it as a post thumbnail.
$wp_filetype = wp_check_filetype( $filename, $mimes );

extract( $wp_filetype );

// no file type! No point to proceed further
if ( ( !$type || !$ext ) && !current_user_can( ‘unfiltered_upload’ ) ) {
return null;
}

// construct the attachment array
$attachment = array(
‘post_mime_type’ => $type,
‘guid’ => $uploads[‘url’] . “/$filename”,
‘post_parent’ => null,
‘post_title’ => ”,
‘post_content’ => ”,
);

// insert attachment
$thumb_id = wp_insert_attachment($attachment, $file, $post_id);

// error!
if ( is_wp_error($thumb_id) ) {
return null;
}

require_once(ABSPATH . ‘/wp-admin/includes/image.php’);
wp_update_attachment_metadata( $thumb_id, wp_generate_attachment_metadata( $thumb_id, $new_file ) );
update_attached_file( $thumb_id, $new_file );
return $thumb_id;
}

/**
* Function to fetch the contents of URL using curl in absense of allow_url_fopen.
*
* Copied from user comment on php.net (http://in.php.net/manual/en/function.file-get-contents.php#82255)
*/
static function curl_get_file_contents($URL) {
$c = curl_init();
curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($c, CURLOPT_URL, $URL);
$contents = curl_exec($c);
curl_close($c);

if ($contents) {
return $contents;
}

return FALSE;
}

/**
* Check whether the required directory structure is available so that the plugin can create thumbnails if needed.
* If not, don’t allow plugin activation.
*/
static function check_permission() {
$uploads = wp_upload_dir(current_time(‘mysql’));

if ($uploads[‘error’]) {
echo ‘<div class=”updated”><p>’;
echo $uploads[‘error’];

if ( function_exists(‘deactivate_plugins’) ) {
deactivate_plugins(‘auto-featured-image/auto-featured-image.php’, ‘auto-featured-image.php’ );
echo ‘<br /> This plugin has been automatically deactivated.’;
}

echo ‘</p></div>’;
}
}

static function add_admin_menu() // Register the management page
{
add_options_page(‘Auto Featured Image’, ‘Auto Featured Image’, ‘manage_options’, ‘generate-post-thumbnails’, array( “Auto_Feautred_Image_Plugin”, “construct_admin_interface”));
}

/**
* Admin user interface plus post thumbnail generator
*
* Most of the code in this function is copied from –
* Regenerate Thumbnails plugin (http://www.viper007bond.com/wordpress-plugins/regenerate-thumbnails/)
*
* @return void
*/
static function construct_admin_interface() {
global $wpdb;
?>

<div class=”wrap genpostthumbs”>
<h2>Auto Featured Image</h2>

<?php
// If the button was clicked
if ( !empty($_POST[‘generate-post-thumbnails’]) ) :

// Capability check
if ( !current_user_can(‘manage_options’) ) wp_die(‘Cheatin’ uh?’);

// Form nonce check
check_admin_referer( ‘generate-post-thumbnails’ );

// Get id’s of all the published posts for which post thumbnails does not exist.
$query = “SELECT ID FROM {$wpdb->posts} p WHERE p.post_status = ‘publish’ AND post_type = ‘post’ AND p.ID NOT IN (
SELECT DISTINCT post_id FROM {$wpdb->postmeta} WHERE meta_key IN (‘_thumbnail_id’, ‘skip_post_thumb’)
) ORDER BY ID DESC”;

$posts = $wpdb->get_results($query);

if ( empty($posts) ) {
echo ‘<p>Currently there are no published posts available to generate thumbnails.</p>’;
} else {

echo ‘<p>We are generating post thumbnails. Please be patient!</p>’;

// Generate the list of IDs
$ids = array();
foreach ( $posts as $post )
$ids[] = $post->ID;
$ids = implode( ‘,’, $ids );

$count = count( $posts );
?>

<div id=”message”>Processing…</div>

function genPostThumb( id ) {
$.post( “admin-ajax.php”, { action: “generatepostthumbnail”, id: id }, function() {
var percentDone = ( processedPostCount / totalPosts ) * 100;

$message.text( “Processing post #” + id + “. ” + Math.round(percentDone) + “% done.” );

processedPostCount++;

if ( postIds.length ) {
genPostThumb( postIds.shift() );
} else {
$message
.addClass(“updated”)
.html(“<p><strong>All done! Processed “+totalPosts+” posts.</strong></p>”);
}

});
}

// start ajax
genPostThumb( postIds.shift() );
});
// ]]>
</script>
<?php
}
else : // button is not clicked
?>
<p>Use this tool to auto generate featured image for your published posts.</p>
<p>If the script stops executing for any reason, just <strong>reload</strong> the page and it will continue from where it stopped.</p>

<form method=”post” action=””>
<?php wp_nonce_field(‘generate-post-thumbnails’) ?>
<p><input type=”submit” class=”button hide-if-no-js” name=”generate-post-thumbnails” id=”generate-post-thumbnails” value=”Generate Thumbnails” /></p>
<noscript><p><em>You must enable Javascript in order to proceed!</em></p></noscript>
</form>

<? endif; ?>
</div>
<?php
} //End afi_interface()

/**
* Process single post to generate the post thumbnail
*
* @return void
*/
static function ajax_process_post() {
if ( !current_user_can( ‘manage_options’ ) ) {
die(‘-1’);
}

$id = (int) $_POST[‘id’];

if ( empty($id) ) {
die(‘-1’);
}

set_time_limit( 60 );

// Pass on the id to our ‘publish’ callback function.
echo self::generate_thumbmail($id);

die(-1);
} //End ajax_process_post()
}

new Auto_Feautred_Image_Plugin();