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Why doesn't Firefox support my H.264 m4v videos ?

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  • 22 have this problem
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  • Last reply by awulb

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Hello,

It seems that Firefox (on Windows 7 and above, and android) supports H.264 codec for html5 video implementation (since version 20). However, it doesn't work on my own website which delivers H.264 videos (in m4v container).
Indeed, when I navigate on the page containing the html5 video player, I can read the following 'error' message : "Video format or MIME type is not supported".

I am using Firefox 23.0 on Windows 7 (and have tried the nightly version to see if it would work with it).
The used doctype is : <!doctype html> Video files are H.264 encoded in m4v containers (I have also tried mp4 containers but it doesn't work better).

Here is how I use the html5 video tag :

<video id="main_video" type="video/mp4" src="..." controls="" poster="...">

It is frustrating because H.264 video works well in this sample page : http://www.quirksmode.org/html5/tests/video.html

Any idea how I could solve my problem ?

Thank you !

Hello, It seems that Firefox (on Windows 7 and above, and android) supports H.264 codec for html5 video implementation (since version 20). However, it doesn't work on my own website which delivers H.264 videos (in m4v container).<br /> Indeed, when I navigate on the page containing the html5 video player, I can read the following 'error' message : "Video format or MIME type is not supported". I am using Firefox 23.0 on Windows 7 (and have tried the nightly version to see if it would work with it). <br /> The used doctype is : &lt;!doctype html&gt; Video files are H.264 encoded in m4v containers (I have also tried mp4 containers but it doesn't work better). Here is how I use the html5 video tag : <pre><nowiki> <video id="main_video" type="video/mp4" src="..." controls="" poster="..."></nowiki></pre> It is frustrating because H.264 video works well in this sample page : http://www.quirksmode.org/html5/tests/video.html Any idea how I could solve my problem ? Thank you !

Modified by cor-el

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Thank your for this piece of advice. The MIME type is correctly set in the .htaccess server side but I realized the url used for the 'src' attribute in my video tag does not contain the file extension, which seems to be problematic with firefox.