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mp4 videos fail to load using <video> tag

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  • Last reply by TyDraniu

crb001
crb001
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I am trying to add an mp4 video to my website using the following code: 

<video width="320" height="240" controls>
  <source src="images/###.mp4" type="video/mp4">
</video>

where ### is the name of the video file. I get the following error message:

"No video with supported format or MIME type found."

In the console the following is displayed:

"Media resource http://127.0.0.1:5502/images/###.mp4 could not be decoded. video.html All candidate resources failed to load. Media load paused. video.html Media resource http://127.0.0.1:5502/images/###.mp4 could not be decoded, error: Error Code: NS_ERROR_DOM_MEDIA_METADATA_ERR (0x806e0006)"

Runs just fine in Chrome and I have no pop-up blockers installed. Autoplay is set to be allowed for all websites.

Windows 11 version 23H2. Firefox version: 126.0 (64-bit)

I am trying to add an mp4 video to my website using the following code: <pre><nowiki> <video width="320" height="240" controls> <source src="images/###.mp4" type="video/mp4"> </video></nowiki></pre> where ### is the name of the video file. I get the following error message: "No video with supported format or MIME type found." In the console the following is displayed: "Media resource http://127.0.0.1:5502/images/###.mp4 could not be decoded. video.html All candidate resources failed to load. Media load paused. video.html Media resource http://127.0.0.1:5502/images/###.mp4 could not be decoded, error: Error Code: NS_ERROR_DOM_MEDIA_METADATA_ERR (0x806e0006)" Runs just fine in Chrome and I have no pop-up blockers installed. Autoplay is set to be allowed for all websites. Windows 11 version 23H2. Firefox version: 126.0 (64-bit)

cor-el modificouno o

All Replies (4)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Does Firefox play the video if you paste its URL in the location bar ?

crb001
crb001 Question owner
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No, it only shows "No video with supported format or MIME type found." Upon further investigation I see that the video used Codec: MPEG-H Part2/HEVC (H.265) (hvc1). Could this be the issue?

TyDraniu
TyDraniu
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crb001 said
No, it only shows "No video with supported format or MIME type found." Upon further investigation I see that the video used Codec: MPEG-H Part2/HEVC (H.265) (hvc1). Could this be the issue?

Yes. You can check your supported codecs in about:support in the Media section.

TyDraniu
TyDraniu
  • Top 10 Contributor
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You can also go to about:config and set media.wmf.hevc.enabled = 1.