Yii count()

 echo Video::model()->count(); 

by using params:
Video::model()->count('video_type <> :type', array('type' => $video_type); 

using commandBuilder:

Yii::app()->db->createCommand()
            ->select('COUNT(*)')
            ->from('video')
            ->where('video_type <> '.$video_type)
            ->queryScalar();