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FF35 H264 Videos Corrupted

  • 3 replies
  • 40 have this problem
  • 531 views
  • Last reply by gaer

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We use mp4 files using the h264 codec on our server to play videos. The files in FF prior to FF35 worked fine, they work in IE8+, and Chrome. In FF35 we now get the following message in the console

Media resource FILEPATH/FILENAME.mp4 could not be decoded.

If we then load the resource directly we get

Video can't be played because the file is corrupt.

Is there something we have to do to the mp4 files to get them working in FF35? This behavior has been replicated on FF35 on OS 10.6.8-10.9, Windows 7, and Windows 8. All systems were updated to FF35 after testing and having the videos play successfully with varying FFs between 32 and 34.

Thanks for any suggestions.

Also if links to the resources would be helpful please let me know.

Attached screenshots

Modified by chris1785

All Replies (3)

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Crashes or other problems with certain multimedia content in Firefox (such as Youtube videos and Flash animations or games) can often be resolved by performing the steps in these Knowledge Base articles:

On Windows Vista and above, you can disable Flash protected mode by following the instructions on these pages:

(See this Adobe blog post for technical details about Flash protected mode.)


For recent updates for Adobe Shockwave Flash, please update your version to 14. Please refer to the security updates and Adobe Security Bulletin for more information.

Please tell us if this helped!

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It doesn't appear specific to any plugin to us. +90% of our videos play fine, it is a limited number that won't play. We could re-encode the videos if we know what setting is causing the issue.

All systems we've tested on play our other video files fine and all the systems fail to play these files. We probably have 250 of the files that aren't working and +4000 of our other video files that are working.

The only difference between the non-working and working videos I can observe is that the non-working videos don't have audio.

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Have the same problem, most of my mp4 videos can be played, but some small part of them can't, and it reproduced only with FF35, tested it with 32 version, everything works fine. Regarding difference between working and non-working videos, for me all of them have audio, here is ffmpeg info for working:

 Metadata:
   major_brand     : isom
   minor_version   : 512
   compatible_brands: isomiso2avc1mp41
   encoder         : Lavf55.19.102
 Duration: 00:00:22.59, start: 0.046440, bitrate: 817 kb/s
   Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 480x270 [SAR 1:1 DAR 16:9], 714 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
   Metadata:
     handler_name    : VideoHandler
   Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 96 kb/s (default)
   Metadata:
     handler_name    : SoundHandler

And non-working file:

 Metadata:
   major_brand     : qt
   minor_version   : 0
   compatible_brands: qt
   creation_time   : 2015-02-13 08:18:00
 Duration: 00:00:56.65, start: 0.004000, bitrate: 897 kb/s
   Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, bt709), 540x960, 840 kb/s, 29.98 fps, 29.97 tbr, 600 tbn, 1200 tbc (default)
   Metadata:
     creation_time   : 2015-02-13 08:18:00
     handler_name    : Core Media Data Handler
   Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 16000 Hz, stereo, fltp, 53 kb/s (default)
   Metadata:
     creation_time   : 2015-02-13 08:18:00
     handler_name    : Core Media Data Handler

The only difference that i can find is a handler_name and creation_time.