How to force play and not download the video

[SivopCi]

Hi there,
I have a problem with fotorama video playback.
Indeed, I don't play youtube videos my videos on my server and when I click to play, it downloads the video...
Do you please have a solution for me?
The title mime of my video is a pm4 and here is my code:

`
<div class="fotorama" data-autoplay="true" data-nav="thumbs" data-transition="dissolve" data-loop="true">
<?php
$image = null;
$video = null;
$image_b = null;
$image_c = null;

	$image   = "images/produits/".$reference.".png";
	$video   = "images/produits/".$reference.".mp4";
	$image_b = "images/produits/".$reference."-b.png";
	$image_c = "images/produits/".$reference."-c.png";

	if(file_exists($image))   {echo '<img src="'.$image.'" class="img-fluid">';}
	if(file_exists($video))   {echo '<a href="'.$video.'" data-video="true"><img src="'.$image.'"></a>';}
	if(file_exists($image_b)) {echo '<img src="'.$image_b.'" class="img-fluid">';}
	if(file_exists($image_c)) {echo '<img src="'.$image_c.'" class="img-fluid">';}
	?>
	</div>

`

Thanks for your help