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why firefox is not Supported H.264 H.264?

  • 5 replies
  • 11 have this problem
  • 12 views
  • Last reply by G-hot

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The newest generation of mainstream internet browsers all support native HTML 5 video playback without the need for third-party plugins like Adobe Flash.

Please refer to this link http://en.wikipedia.org/wiki/HTML5_video for the details.


Once the videos are converted to HTML5 compatible video files, you can embed it into your web pages. However, different browsers support different video codecs. Currently, Ogg Theora, H.264 and WEBM/VP8 are used in the different html 5


Browsers Ogg Theora H.264 WebM/VP8 IE 7/8 No <video> support No <video> support No <video> support IE 9 Not Supported Supported Supported only if user installs WebM for IE9 Chrome Supported Not Supported Supported Firefox Supported Not Supported Supported Safari Not Supported Supported Not Supported Opera Supported Not Supported Supported

The newest generation of mainstream internet browsers all support native HTML 5 video playback without the need for third-party plugins like Adobe Flash. Please refer to this link http://en.wikipedia.org/wiki/HTML5_video for the details. Once the videos are converted to HTML5 compatible video files, you can embed it into your web pages. However, different browsers support different video codecs. Currently, Ogg Theora, H.264 and WEBM/VP8 are used in the different html 5 <video> tag implementations by the browser vendors including Internet Explorer(IE), Moziila Firefox, Google Chrome, Apple Safari and Opera. Browsers Ogg Theora H.264 WebM/VP8 IE 7/8 No <video> support No <video> support No <video> support IE 9 Not Supported Supported Supported only if user installs WebM for IE9 Chrome Supported Not Supported Supported Firefox Supported Not Supported Supported Safari Not Supported Supported Not Supported Opera Supported Not Supported Supported

Modified by G-hot

All Replies (5)

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  1. In the Location bar, type about:config and press Enter. The about:config "This might void your warranty!" warning page may appear.
  2. Click I'll be careful, I promise!, to continue to the about:config page. Now type media.windows-media-foundation.enabled' and when the value shows double click it, it should be bold (and saying true) and h.264 shall playback.

Modified by kobe

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i don’t see "be bold" anywhere? and i have this set to media.windows-media-foundation.enabled;boolean true

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Hello G-hot, i think the problem is your os (xp), see:

To avoid patent issues, support for MPEG 4, H.264, MP3 and AAC is not built directly into Firefox. Instead it relies on support from the OS or hardware. Firefox supports these formats on the following platforms: Platform Firefox version Windows 7+ 21.0 Windows Vista 22.0 Android 20.0 Firefox OS 15.0

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


thank you

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Why only for Vista and 7?Man Add this for the XP system