php readfile（）仅在某些视频文件上提供错误500

Question

I have a problem with displaying some videos via a php script using readfile(). Some videos give a HTML status 500, others work fine. Something I do wrong, but I have no idea what. Can somebody hint me in the right direction? What might be the reason for error 500 ?

This is a simplified example I tested on my localhost to reproduce the error.

calling script:

<?php
  $videofiles=array("1.mp4", "2.mp4", "3.mp4", "4.mp4");
  for ($i=0; $i < count($videofiles); $i++) {
?>
    <div class="videos">
    <video controls>
        <source src="video.php?v=<?php echo $videofiles[$i]; ?>" type="video/mp4">
    </video>
    </div>
<?php
  }
?>

delivering script video.php:

<?php
  $video=$_GET['v'];  
  header("Content-Type: video/mp4"); 
  header("Content-Length: ".filesize($video));
  readfile($video);
?>

All rights are set correct (if I replace "video.php?v=..." by the direct filepath all videos show). I suspect that it has to do with file size - the larger (> 150MB) are those who do not show, but I don't know... for testing I used videos from the same mobile phone and of the same day without altering them.

Answer 1

Thanks for the answers!

I found in the error log:

PHP
Fatal error:  Allowed memory size of 134217728 bytes exhausted (tried to
allocate 138174464 bytes)

After that I inserted in the script

ini_set('memory_limit', '400M' );

this solved the problem.