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What is gmpopenh264.dll?

  • 3 replies
  • 1 has this problem
  • 1 view
  • Last reply by cor-el

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I see that it's supposed to be an add-on for Firefox. Norton has told me that it is safe and a very commonly downloaded file, but an online search has given me conflicting reports, with many sites saying that it is a virus.

I see that it's supposed to be an add-on for Firefox. Norton has told me that it is safe and a very commonly downloaded file, but an online search has given me conflicting reports, with many sites saying that it is a virus.

Chosen solution

There is always a possibility that a virus uses the same name as a legitimate file. If Firefox downloaded and installed the file automatically and placed the file in the gmp-gmpopenh264 folder in the profile folder then it should be fine. If the file is located elsewhere then something is wrong.

For plugins you can check their location on the about:plugins page that you can open via the location/address bar.

This plugin is automatically installed by Mozilla to comply with the WebRTC specification and to enable WebRTC calls with devices that require the H.264 video codec. Visit https://www.openh264.org/ to view the codec source code and learn more about the implementation.
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The gmpopenh264.dll file is the OpenH264 video Codec that is used in WebRTC to play DRM protected content. See "Add-ons -> Plugins" (about:addons).

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Thanks. Why are there so many sites saying it's a virus?

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Chosen Solution

There is always a possibility that a virus uses the same name as a legitimate file. If Firefox downloaded and installed the file automatically and placed the file in the gmp-gmpopenh264 folder in the profile folder then it should be fine. If the file is located elsewhere then something is wrong.

For plugins you can check their location on the about:plugins page that you can open via the location/address bar.

This plugin is automatically installed by Mozilla to comply with the WebRTC specification and to enable WebRTC calls with devices that require the H.264 video codec. Visit https://www.openh264.org/ to view the codec source code and learn more about the implementation.