Is there a way to tell the file size of an .ogg video before it is fully loaded?

问题

I know one difference between ogg video and mp4 video is that ogg video doesn't have metadata describing the file size, so when an ogg video is loaded, the controls can't show the time remaining until the file has fully loaded. This can be a problem if the ogg video is more than a few minutes long. Is there a way to get this filesize when the page is requested?

(Client-side developer, asking a question that I think has a server-side answer. I welcome suggested edits to this question, if you can think of a way to ask it more specifically.)

回答1:

Well although not the most direct, you could try this.

First, set up a .htaccess to transparently grab all .ogv videos and process them with PHP

.htaccess

RewriteEngine On
RewriteRule ^(.*)\.ogv$ ogv.php?file=$1

ogv.php

<?php
$file = $_GET['file'] . '.ogv';

while ( strpos($file, '..') !== false )
{
    $file = str_replace('..', '', $file);
}

$filesize = filesize($file);

header("Content-Type: video/ogg");
header("Content-Transfer-Encoding: binary"); 
header("Content-Length: {$filesize}");
readfile($file);
exit()
?>

HTML:

<video src="video.ogv" id="video" controls></video>

<script>
var video_src = document.getElementById('video').src;
var xhr = new XMLHttpRequest();
xhr.open('GET', video_src, false);
xhr.send(null);
var size = xhr.getResponseHeader('Content-Length');
alert(size);
</script>

So here's how this system works. Just link a .ogv video like normal but the .htaccess file captures the request first and sends it to ogv.php. The PHP file then specifically sends out a file size header in case the server doesn't automatically. Okay, that still doesn't do you a whole lot of good, right? Well, you can then make an Ajax request for the video and extract the filesize from the HTTP headers.

Hope this helps.

来源：https://stackoverflow.com/questions/5333800/is-there-a-way-to-tell-the-file-size-of-an-ogg-video-before-it-is-fully-loaded