Corrupt VOD File

[dchadd]

Hi guys. We had an issue with our VOD file recorded with our teradek cube. It seems to have gotten corrupt. I have tried numerous recovery programs and all dont seem to be working. I am kind of desperate. Is anyone able to help? Thanks.


Good File
https://drive.google.com/open?id=0B5pYxuLXfvPFTHVFOVQ0V1dhclE
Bad File
https://drive.google.com/open?id=0B5pYxuLXfvPFU3Q2YTNGLVZjOHM

[Baldrick]

Tried graus video repair tool?

(I tried it...and it crashed...)

[dchadd]

I did try it and every other tool I could find. I think the issue is that the cube isn't a device that people use file recovery on often. So these programs don't understand the file structure.

Anyone know how to manually rewrite the header and footer to make it work?

[Baldrick]

Use a hex editor and try replace or add some of the beginning from another file. Then run it through video repair tool.

[dchadd]

It's not even detecting the codec on the reference file.


Repair session information
Input file: C:\Users\dchadd\Desktop\Cube_255_02761-tc051516_145352 - Copy.mp4 (623433164 bytes)
Reference file: C:\Users\dchadd\Desktop\Cube_255_02761-tc051516_124756.mp4
Output folder: C:\Users\dchadd\Desktop\repaired\


Entropy scan results
Your complete input file has been analysed in small blocks, and the entropy results show which blocks may contain video data (and which may not). A value less than 0.6 typically means that there is definitively no video data in that block, a value greater than 0.6 means it may contain video data.
start block (KB) - end (KB) -- entropy (must be higher than 0.6 for video data)
--------------------------------------------------------------------------------------------



Video scan results
Your complete input file has been analysed for video data and this shows the amount of data found. Note: If no data was found (or less than expected), the entropy scan result above can give you an explanation why no (or not enough) data was found. Video data found: 0 bytes (DEMO version saves only 50% of this)
Audio data found: 0 bytes (DEMO version saves only 50% of this)


Your reference movie
Video codec:
Audio codec:

[JVRaines]

I did try it and every other tool I could find. I think the issue is that the cube isn't a device that people use file recovery on often. So these programs don't understand the file structure.

I doubt that's the problem. According to the manufacturer, Cube uses h.264:

VIDEO CODEC
Compression Algorithm: Baseline, Main and High Profile H.264
Main and Baseline profiles
Bit Rate: 250 Kbps to 10 Mbps

More likely your file is so trashed that it doesn't look anything like h.264.

[dchadd]

I doubt that's the problem. According to the manufacturer, Cube uses h.264:

Well what is weird to me about that is the "good working file" for reference isn't being detected by the recovery program. It cannot tell what audio or video codec it is using in the report.

Your reference movie
Video codec:
Audio codec:

Teradek is trying on their end to help, just waiting to hear back if they could fix it or not. Sounds like a common thing because he said "sometimes we can sometimes we can't." Thanks so much for trying I appreciate it.

[dchadd]

Hey guys,

Thanks for all your help. Teradek was able to fix the file headers and make the file work. No information was lost. I am asking to see if they can tell me what they did for the future and if they share I will post it here. The file headers in the hex editor look totally different than the reference working file even.

Thanks again.

[dchadd]

Here is some information from our engineers:

The software untrunc was used to recover your video.
If still experiencing you can try to to "semi-manually" reconstruct the moov atom, which is a tedious process. They use Apple's documentation of the MOV / QuickTime format, which is practically interchangeable with the MP4 format (for typical videos).

Hope this helps.

Here was their reply.

[JVRaines]

Thanks for posting about untrunc. Never heard of it but sounds promising. Looks like it's only for Linux at the present time.

[Baldrick]

Yep. untrunc sounds interesting. But I can't even build untrunc in linux....even after I installed libav....avcodec.h is missing.

edit: Fixed now. Testing with your file now.

edit2: Yep. It worked fine. I'm now going to build a windows version of untrunc...I have no idea how though...maybe cygwin.