i don't see any html5 video tags all i see is flashplayer stuff.

I have tinkered with html5 before and i know what you are doing, a flash fall back.

It looks like this is a flash player crash issue.

Since firebox does not support mp4 codec it is calling upon flash player to run the mp4 file wrapped in flash, and its most likely flash player causing it to crash, not the html5 coding. loost the flash player wrapper and encode you video with webm or ogg which Firefox natively supports and you will have no need for the extra coding to support the mp4

i have some unorthodox flash player crash solutions that have worked, but you wont find them on this forum.

Click on my profile name here, and you will find a link.

Best Regards

Try this html file:

https://drive.google.com/file/d/0B4NWT1D6VPzsd2tpZVVMQ1VQT0k/edit?usp=sharing

It opens just fine on my machine in Firefox and its simple html5

You shouldn't need to paste long crash reports in the forum. When Firefox crashes, it usually records information about what was happening at that moment. You can submit that data to Mozilla and share it with forum volunteers to see whether it points to the solution. Please check the support article "Firefox Crashes" (especially the last section) for steps to get those crash IDs from the about:crashes page (the linkable ones will start with bp-), and then post some of the recent ones here.

Thanks all for your helpful replies.

I have changed the video source code now to:

<video id="video" autobuffer height="280" width="520" controls>
	 <source src="" >
	<source src="file:///C:/RPD_Computing_Programming/.......oggtheora.ogv"type="video/ogg">	 
  Your browser does not support the <code>video</code> element.
</video>

I use .ogv video file instead of .mp4 and Firefox handles this file fine now (with over 60 video player instances on the page). It was a while since I had last tried HTML5 video and I had forgotten it is not exactly straightforward with which browser supporting different formats.

Many thanks-all is fine for now :-)

Firefox should be able to play MP4 files via the video tag if Windows Media Foundation (media.windows-media-foundation.enabled = true) is working properly.

• http://www.ghacks.net/2013/05/10/hardware-accelerated-h-264-playback-coming-to-firefox-23/

If the player crashes with some mp4 file then it is possible that you have to recode the file.

Did you try each file individually to make sure they all work?

" Firefox should be able to play MP4 files via the video tag if Windows Media Foundation (media.windows-media-foundation.enabled = true) is working properly.

   http://www.ghacks.net/2013/05/10/hardware-accelerated-h-264-playback-coming-to-firefox-23/ 

If the player crashes with some mp4 file then it is possible that you have to recode the file.

Did you try each file individually to make sure they all work? "

I guess Mozilla are paying royalties to MMPEG-LA now ( https://developer.mozilla.org/en-US/docs/HTML/Supported_media_formats ) Last time i did any web stuff it didn't support. Also it cannot use the HIGH profile for lower machines, so depending on how iy was encoded and the particular machine.

Anyway the OP seemed to understand the html5 coding now, and should now be able to move forward on the format of his choosing

Best regards

Firefox uses OS means to play these files, so it won't work if you haven't installed the proper Windows Media Foundation support on Windows Vista and later.

• http://msdn.microsoft.com/en-us/library/windows/desktop/ms696274%28v=vs.85%29.aspx

I never had to do anything like that to get it to work, and just tested it, and it works just fine. In order to support mp4 the codec has to be supported in Firefox, i studies this quite some time ago and know that i never installed any of that. That is why Firefox can play webm right out of the box. There is no native support for webm in windows, thats why you have to use VLC to play it natively BECAUSE VLC HAS THE CODEC embedded AS THE SAME WITH MKV and i didn't have to go fiddling around with any Windows Media Foundation support, that is because the codec has to be supported within the browser, the OS does not run it unless you download it and play with a native player. Everything is handled within the browser.

Hi Carm, MPEG decoding is dependent on platform support, the patented technology isn't built in to Firefox.

You might want to read the articles that i posted as quoted: " Mozilla will release Firefox 21 next Tuesday and with it comes H.264 support to the browser " As it looks like you didn't read this. IF mpeg decoding was dependent on the platform there would have been no need for this article and support within the browser, right?

http://www.ghacks.net/2013/05/10/hardware-accelerated-h-264-playback-coming-to-firefox-23/

Since you are only partially correct in this matter. IF the browser calls say WMP to run the content then it is running it from the OS.

If you require proof, download opera and try running pure HTML5 code as in my example above and see if mp4 file is indeed dependent on the operating system or browser. OPERA DOES NOT SUPPORT MP4 Can you get it to play natively in the browser? I think with a little reading of the articles i posted as 100% PROOF i know what i am talking about.

There is also proof here:

https://developer.mozilla.org/en-US/docs/HTML/Supported_media_formats

and

https://hacks.mozilla.org/2012/03/video-mobile-and-the-open-web/

I can say that i dealt with this over two years ago and studies it in a professional working environment with a user base of over 10,000, so i do know that this is a 100% browser support issue unless you are calling WMP for example to handle mp4 content, that is completely different matter as talking about playing natively in the browser using html5

WMP is the Windows Media Player and that is a dedicated media player.

Windows Media Foundation (WMF) is a library (API) that other programs can call to perform specific tasks and in this case decoding H.264 and other media formats that it supports as you can read here:

• http://msdn.microsoft.com/en-us/library/windows/desktop/bb970511%28v=vs.85%29.aspx
• AAC decoder
• AAC encoder
• AVI/WAVE file source
• DV video decoder
• H.264 video decoder
• H.264 video encoder
• MJPEG decoder
• MP3 file sink*
• MP4/3GP file source
• MP4/3GP file sink

So do not confuse the two.

This only applies to windows, and i understand, that still does not explain why the opera browser does not play mp4 files. Hence the browser has to provide support for this.

IF windows indeed did provide support for this then using html5 in opera should pose no issue, correct?

Also it is important to note that windows does not support ogg, ogv, mkv, webm. However the Firefox browser can play them which means they do the decoding

Hi Carm, MPEG is a special case due to patents. Where the platform provides the decoding service, then Firefox can discover and hook into it.

You are correct that older versions of Firefox didn't even bother to try hooking into these decoding APIs. That was for "political" reasons, because Mozilla sought to drive everyone to use only open (not patent encumbered) codecs. Google had promised to go along with that, but never did, leaving Firefox as the lonely holdout, and Firefox users stuck using plugins to play MPEG-encoded media.

Since that was a losing battle, Firefox has gradually been adding support for these external decoders. On Windows Vista and higher, this is the Media Foundation API, and on Windows XP, Firefox 26 now uses DirectShow (I don't know what that is, actually). On Linux there is gstreamer, and on Mac, it's not yet possible. Android platforms are a mixed bag as well.

The browser needs to have support for using this API.
Firefox has added support, but Opera apparently not if it doesn't work.
Google Chrome has built-in support for a lot of formats.

• Bug 799318 - [meta] Support H.264/AAC/MP3 video/audio playback on desktop Firefox
• Bug 799315 - Windows Media Foundation backend for media playback (Vista and later)

• Bug 794282 - Enable GStreamer in official builds (Linux)
• Bug 851290 - Use GStreamer on Mac for H.264/MP3/AAC playback (instead of AV Foundation)

(adding to cor-el's list) Firefox 26/Windows XP/DirectShow:

• Bug 861693 - DirectShow backend for MP3 decoding on WinXP

P.S. I marked this question "solved" based on the last post by richardpd