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I’m preparing to update some old pages to HTML5, and was surprised to see that it worked in Chrome, but not the latest Firefox (v.33.1... also tried v.32). What is odd is this... In Firefox it actually WILL play IF you "coax it". If you move the video position slider to someplace beyond the start (about 5 seconds in) and THEN click play, all is well. Further inspection showed that when I click play, the file pointer was jumping to the end of the file leaving my "poster" photo intact, leading the viewer to think there is nothing else they can do. If, however, you manually move the pointer back to anyplace beyond the first couple of seconds of the file (really !), and THEN click the PLAY button, FF will play the rest of the video fine.

Sometimes i think that to the more technically minded among us, the universe doles out the weirder problems, while God laughs.

I’d suspect video file corruption, but all my conversions were made with the very reliable ffmpeg utility, and tested with VLC. Again, it works fine from Chrome, which supposedly uses the same video format. Here’s a link...

FF will play the older type ogv files, so if this is one of those things where FF, now at version 33 is at fault, I’ll have to detect the browser and write the order myself with a document.write(). But it would be nice to know if there is a more straigh forward solution.

Note that I have tried adding the mime types to my HTACESS file. But the fact that the behavior is the same when point my browsers directly the file on my local machine, makles me doubt that is the problem.

http://pixyland.org/peterpan/OurWedding2a.html

And here is the page code

  







    



    















<table align="center" border="1"><tr><td align="center">

<div align="center">



<video width="640" height="480" controls="controls" poster="Imagezz/Wedding/arIMG_2280.JPG">

 <source src="../vids/Arrival.mp4" type="video/mp4">  

 <source src="../vids/Arrival.webm" type="video/webm"> 

 <source src="../vids/Arrival.ogv" type="video/ogg"> 





 

 <p>If you are unable to view the video, here are some links to download <br />

  in a a few well supported video formats. You may be able to just download <br />

  and play one of these files without the browser.<br /><br />

  <strong>Download Video:</strong>nbsp;

    nbsp;<a href="http://stackoverflow.com/feeds/vids/Arrival.mp4">"MP4"</a>

    nbsp;<a href="http://stackoverflow.com/feeds/vids/Arrival.webm">"WEBM"</a>

    nbsp;<a href="http://stackoverflow.com/feeds/vids/Arrival.ogv">"Ogg"</a>

 </p>



 </source></source></source></video>

 </div>

 </td></tr></table>

Version 32 of Google’s Chrome web browser introduced this nifty feature :

When a browser tab has an element that is producing audio, the browser’s tab shows the above audio notification icon to inform the user. I have seen that people have a few questions about this, specifically :

1. How does this feature work ?
2. Why wasn’t this done sooner ?
3. Are other browsers going to follow suit ?

Short answers : 1) Chrome offers a new plugin API that the Flash Player is now using, as are Chrome’s internal media playing facilities ; 2) this feature was contingent on the new plugin infrastructure mentioned in the previous answer ; 3) other browsers would require the same infrastructure support.

Longer answers follow…

Plugin History
Plugins were originally based on the Netscape Plugin API. This was developed in the early 1990s in order to support embedding PDFs into the Netscape web browser. The NPAPI does things like providing graphics contexts for drawing and input processing, and mediate network requests through the browser’s network facilities.

What NPAPI doesn’t do is handle audio. In the early-mid 1990s, audio support was not a widespread consideration in the consumer PC arena. Due to the lack of audio API support, if a plugin wanted to play audio, it had to go outside of the plugin framework.

There are a few downsides to this approach :

• If a plugin wants to play audio, it needs to access unique audio APIs on each supported platform. One of the most famous things I’ve ever written deals concerns this nightmare on Linux. (The picture worth a thousand words.)
• Plugin necessarily needs free unrestricted access to system facilities, i.e., security measures like sandboxing become more difficult without restricting functionality.
• Since the browser doesn’t mediate access to the audio APIs, the browser can’t reasonably be expected to know when a plugin is accessing the audio resources.

So that last item hopefully answers the question of why it has been so difficult for NPAPI-supporting browsers to implement what seems like it would be simple functionality, like implementing a per-tab audio notifier.

Plugin Future
Since Google released Chrome in an effort to facilitate advancements on the client side of the internet, they have made numerous efforts to modernize various legacy aspects of web technology. These efforts include the SPDY protocol, Native Client, WebM/WebP, and something call the Pepper Plugin API (PPAPI). This is a more modern take on the classic plugin architecture to supplant the aging NPAPI :

Right away, we see that the job of the plugin writer is greatly simplified. Where was this API years ago when I was writing my API jungle piece ?

The Linux version of Chrome was apparently the first version that packaged the Pepper version of the Flash Player (doing so fixed an obnoxious bug in the Linux Flash Player interaction with GTK). Now, it looks like Windows and Mac have followed suit. Digging into the Chrome directory on a Windows 7 installation :

AppData\Local\Google\Chrome\Application[version]\PepperFlash\pepflashplayer.dll

This directory exists for version 31 as well, which is still hanging around my system.

So, to re-iterate : Chrome has a new plugin API that plugins use to access the audio API. Chrome knows when the API is accessed and that allows the browser to display the audio notifier on a tab.

Other Browsers
What about other browsers ? “Mozilla is not interested in or working on Pepper at this time. See the Chrome Pepper pages.”