Video script

<html>
    <head>
        <title></title>

        <script type="text/javascript" src="jquery.min.js"></script>
        <script type="text/javascript">
            function videoEnded() {
                //Function called when the video is ended
                //We add a GET video to call our php function
                window.location.href = window.location.href+"?video=1";
            }
        </script>
    </head>

    <body>
        <?php
            if(isset($_COOKIE["alreadysawvideo"]))
            {

                //If the cookie is already set, then the video has already been saw
                //So we just redirect the user to the page we want.
                header("location: http://yoursite.com");

            } else if (!empty($_GET['video'])){

                //If the video GET thing is not empty it means the user just saw the video we can redirect him to the website
                //We add a cookie to remember for the next time that he already saw the video
                $year = time() + 31536000;
                setcookie('alreadysawvideo', 1, $year);

                header("location: http://yoursite.com");
            }
        ?>
        <video src="yourvideo.mp4" id="video" controls onended="videoEnded()"></video>
    </body>

</html>