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  1. Hello,

    I am a total newbie and not an enthusiast in the video area. Frankly with all respect, I am simply not interested in getting a second education in the field just to fix one video. Time is money, and I am willing to pay for one's time, just as I would expect someone to pay for mine in a relevant field. A link to a professional service that deals with that is appreciated as well. Contact me via this thread with your offers.

    Quick rundown of the situation:
    Video's recorded via a Sony digital camera in mp4 format. One video was deleted in camera by accident and recovered at the PC later on. As far as I remember no activity on the card after that deletion until recovery. 3 files from the session. 1 is 30mb and is fully functional with all atoms intact, showing streams in Mp4Creator. 2 Other files seem to have corrupt headers, the main file I need repaired is 230MBs, corrupt header, but footer seems to be intact, not truncated. At least per my limited understanding via WinHex. The 2nd 4mb file is missing both, but I am not really concerned with it.

    The functional mp4 info:
    MSNV: MPEG-4 (.MP4) for SonyPSP
    - mp42: MP4 v2 [ISO 14496-14]
    - isom: MP4 Base Media v1 [IS0 14496-12:2003]
    Recommended Display Size: 1280 x 720
    Created: 2009 Sep 09 22:24:51
    Modified: 2009 Sep 09 22:25:18


    mp4a: MPEG-4 AAC LC
    24000Hz 128 kb/s tot , stereo (2/0)

    mp4v MPEG-4 Video Stream is MPEG-4
    P-VOP

    9000kpbs Qf 0.326 Pics/s 29.971 Frames = same
    1280x720 sar 1.778 par 1.00 dar 1.778
    -------------

    So the 230MB file would have identical info, as it was recorded within a minute of the functional one.

    This might be an easy fix, or be impossible at all. Please chime in if your knowledgeable, as to if you can help and your fee.

    MOD:If my post is against TOS, please advise and I will correct.
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  2. Do you still have the flash card? And have you avoided using the card since the file was deleted and recovered? That's where proper recovery needs to start. The file that was "recovered" may have nothing useful in it.
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  3. No the card is not available any longer. I do not remember what I used to recover the file from the stick, but I distinctly remember that once my wife deleted the file in camera, I have told her to turn it off and not use it. Recovery was done first thing after getting home. I understand that there might be nothing useful in the file, but hope it is not true, as there was no action to possibly overwrite the data. WinHex does show a proper ending of the file, but the header is messed up. As to the rest of the data - no idea.
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  4. Because of the way the FAT file system is set up it's unusual that the beginning of the undeleted file is messed up -- unless files were written to the drive after the file was deleted.

    In the FAT file system the directory entry points to the first cluster of the file. Then the rest of the file is located via the FAT (file allocation table, a linked list of used/free clusters). When the file is deleted the linked list in the FAT is zeroed out (marking those clusters as free again), and the directory entry marked unused by overwriting the first character of the filename with a special token. The rest of the directory entry is not overwritten. So the pointer to the first cluster and the file size are still valid. File recovery software usually starts with that first cluster then assumes that successive free clusters constitute the rest of the file (which is not the case if the file is fragmented). So if the very first cluster is not a part of the file the implication is that another file was written to the drive (and used that cluster) after the file was deleted.

    Even with the first cluster of the file obliterated it still might be possible to recover other parts of the video. As you know the beginning of the file usually has information about the video and much of that information is exactly the same as in other videos from the camera. You might be able to copy the header data from a similar sized (or longer) MP4 file and then use some mp4 repair utility to extract usable parts of the file. I don't deal much with MP4 so I can't recommend anything.

    Cluster size can range from 2 KB to 64 KB depending on the size of the drive. Some disk utilities will tell you the cluster size if you still have the card or another card of the same size and format.
    Last edited by jagabo; 21st Feb 2010 at 19:36.
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  5. Thanks for the info. I am playing around with the file, trying to copy the header. The idea with recording a file close in length to original is nice, I will try. At least it would be a better option to compare than the working 30 meg file I have.
    Waiting on others to chime in, as well as perhaps take me up on the offer.
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  6. Member
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    Hi there, came to notice your post on the corrupted mp4 video file. Would you please shed some light for my corrupted mp4 video file too? Just one file (13.3MB) which I took during my trip to Thailand from a mobile phone. I have tried all my best in searching up google for many solutions thus it didn't help. I guess my best bet is to add the mp4 header which I have completely no idea where to copy and paste it into.
    I hope you can help me or point me in the right direction on fixing this.

    Million of thanks..... Appreciate your kind help.

    Regards,
    Vincent
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    Vince normally this is performed simply by overwriting the bad one with a known good one.
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  8. Member
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    Originally Posted by lowellriggsiam View Post
    Vince normally this is performed simply by overwriting the bad one with a known good one.
    Hi lowellriggsiam,
    How do we go around in overwriting the bad one with a known good one.
    There are so many data in WinHex.

    I've checked with WinHex on the mp4 video file and there is a big chunk of '0' at the beginning of the file but there seems to have data starts from Offset:523773 onwards.
    Any further advice?
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  9. Member
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    Originally Posted by greymfm View Post
    You could try to use this tool to repair corrupted movie files (MP4 and some other):

    http://grauonline.de/cmsimple2_6/en/?Solutions:HD_Video_Repair_Utility

    However, the tool will require a non-broken sample movie file of the same camera - this file is used to repair the corrupted one.
    IT WORKS!! Thank You, greymfm!! Appreciate your kindness in sharing that mp4 Repair Utility!
    My video capture device (Nokia N82) doesn't listed on the grauonline.de website but I've gave it a try, it works perfectly!!
    My video file is a .mp4, H.263 format.

    Here are the correct guides for people who wants to give it a try on the mp4 Repair Utility.
    1. Download the mp4 Repair Utility from http://grauonline.de/cmsimple2_6/en/?Solutions:HD_Video_Repair_Utility
    2. Extract the 'videorepair.zip'
    3. On a Windows PC, run 'guiscript.exe'
    4. Click 'Choose Movie' pick the damage mp4 video file.
    5. Click 'Choose reference movie' to load the playable mp4 video that uses the same video capture device.
    6. Press 'Scan'
    7. If the video is fixed, it will displayed in the white box and you can preview the video file.
    (As you can see, blank if movie was not repairable)

    Note: If the repaired mp4 video appears very choppy, try load other reference movie from the same video capture device.
    Good luck!!
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