For now, we'll only search for "mp4" files (download_functions.php)

In the future, we'll need to add analysis of all files for merging and use that to decide on the output file format.

web/includes/download_functions.php

@@ -105,7 +105,7 @@ function downloadEvents(
     $maxTimeSecs = -1;
     $maxTime = '';
     foreach ($events_by_monitor_id[$mid] as $event) {
-      $filePath = findVideoEventFile($event);
+      $filePath = findVideoEventFile($event, "mp4");
       if ($filePath ==='') {
         ZM\Warning('The file path for event '.$event->Id().' was not found.');
         continue;