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No H.264 support in HTML5, Firefox 49, Linux

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  • 33 have this problem
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  • Last reply by AliceWyman

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Hi, my Firefox doesn't have support for H.264 decoding, although ffmpeg and other software compiled with support for it. According to https://www.youtube.com/html5 there is no H.264 and MSE & H.264 support. On pages with html5

Hi, my Firefox doesn't have support for H.264 decoding, although ffmpeg and other software compiled with support for it. According to https://www.youtube.com/html5 there is no H.264 and MSE & H.264 support. On pages with html5 <video> tag with type="video/mp4" Firefox tells "Video format or MIME type is not supported". At about:support page there is line: "Supports Hardware H264 Decoding = No; Failed to create H264 decoder". I have recompiled Firefox with --enable-debug, and now I see the error "[6748] WARNING: Unable to create a decoder, no platform found.: file /var/tmp/portage/www-client/firefox-49.0/work/firefox-49.0/dom/media/platforms/PDMFactory.cpp, line 153". Video driver is the nvidia proprietary driver. I also ask this question in this thread (with additional info related to distrib) https://forums.gentoo.org/viewtopic-t-1054580.html. Please help.

Chosen solution

I have found the cause of the problem, it is Plex Media Server. This package contains libavcodec.so.57 which Firefox tries to link against and fails to do so (system-wide installed ffmpeg contains libavcodec.so.56).

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Chosen Solution

I have found the cause of the problem, it is Plex Media Server. This package contains libavcodec.so.57 which Firefox tries to link against and fails to do so (system-wide installed ffmpeg contains libavcodec.so.56).

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(For the record) For details on the problem and its solution, see this thread that nshibalov posted on the Gentoo Forums: https://forums.gentoo.org/viewtopic-p-7991240.html?sid=38ed7080bf31ac898795875a04c62f4e [SOLVED] Firefox 49, no H.264 support