controller.php

<?php

public function clipGetVideo($request, $response, $args) {
	$clipid = $args['clipid'];

	$clip = GameClip::where('id', $clipid)->first();

	$fh = fopen($clip->File, 'rb');
	$stream = new \Slim\Http\Stream($fh);

	$file_size = filesize($clip->File);
	$seek_end   = (empty($seek_end)) ? ($file_size - 1) : min(abs(intval($seek_end)),($file_size - 1));
	$seek_start = (empty($seek_start) || $seek_end < abs(intval($seek_start))) ? 0 : max(abs(intval($seek_start)),0);

	$response = $response
		->withBody($stream)
		->withHeader('Content-type', 'video/mp4')
		->withHeader('Content-length', filesize($clip->File))
		->withHeader('Content-Range', sprintf("bytes %d-%d/%d", $seek_start, $seek_end, $file_size))
		->withStatus(206);

	return $response;
}