-// Compute the thumbnail for a link.
-//
-// With a link to the original URL.
-// Understands various services (youtube.com...)
-// Input: $url = URL for which the thumbnail must be found.
-// $href = if provided, this URL will be followed instead of $url
-// Returns an associative array with thumbnail attributes (src,href,width,height,style,alt)
-// Some of them may be missing.
-// Return an empty array if no thumbnail available.
-function computeThumbnail($url,$href=false)
+/**
+ * Compute the thumbnail for a link.
+ *
+ * With a link to the original URL.
+ * Understands various services (youtube.com...)
+ * Input: $url = URL for which the thumbnail must be found.
+ * $href = if provided, this URL will be followed instead of $url
+ * Returns an associative array with thumbnail attributes (src,href,width,height,style,alt)
+ * Some of them may be missing.
+ * Return an empty array if no thumbnail available.
+ *
+ * @param ConfigManager $conf Configuration Manager instance.
+ * @param string $url
+ * @param string|bool $href
+ *
+ * @return array
+ */
+function computeThumbnail($conf, $url, $href = false)