Php Buffer a video file

Question

On my website I have a video player the video is taken from another server, the problem is that the video player play the video in real time, there is no chance to move it on the timebar. I have to make the function which will buffer the file to make sure that users can move the video on the timebar.

The timeline is working but after a while (about 30 min when the video finally is on the user computer)

I think that I have to create a while loop that will all the time refresh the video so user will see how the file is buffering on the timeline.

Basically right now there is no white bar on the timeline, there is just a blue one, and the white bar shows when the video is fully loaded :

Example : https://i.stack.imgur.com/6GHKk.png

I try to make this look, I starts with this :

$videolink = "example.com/video.flv";
if (is_file($videolink)) {
header('Content-Type: video/x-flv');
header("Content-Disposition: attachment; filename=video.flv");
$fd = fopen($filename, "r");
while(!feof($fd)) {
    echo fread($fd, 1024 * 5);
    flush_buffers();
    }
fclose ($fd);
exit();
}

But well, it doesn't work... the video not playing.

does anyone know how to fix it ??