WHILE RECORDING, IF THE POWER SUDDENLY CUT OFF, ZERO KB RECORDED FILE.

[mete]

We are studying about a project in which is used Neuros MPEG4 Recorder 1. While dealing with this project, we had a problem. This problem is:
While recording, if the power suddenly cut off, we always see that the capacity of recorded file inside the memory card shows 0 (zero) KB. So, we are not able to get recorded files in sudden cut off power.
a. Has this problem been solved in any firmware? (or Neuros MPEG4 Recorder 2)
b. Is this problem caused whether from software or hardware?
c. Is there any way to recover this type of files?

[bobkart]

I seriously doubt that this problem can be fixed.  Without power, there is no course of action available to the recorder.  It is definitely a hardware problem.

Once could envision a system that doesn't suffer from this shortcoming, in which the output file was closed/reopened on a periodic basis (every second perhaps), then the most you could lose would be one second.  So with that possibility it could be argued that it could be fixed in the firmware.  Tough to say without knowing more.

As far as recovering the lost file, some utility that can recover deleted files may have a chance.  Data has been written to the card, but since the file never got closed, the connection from the file system isn't there.  Simialr to a file that has been deleted.  In the absence of such a recovery, formatting of the memory card is a last resort, to regain the lost capacity, but that won't get the lost data back.

I would suggest trying to make it so you don't lose power unexpectedly.  Batteries perhaps?

[dongle]

mete posted this topic in three different areas on this forum which is not really a good idea.

I did post an answer in another area and agree with bobkart. However a deleted file is not physically erased from the medium, its attributes are changed within the master file table (mft) which then shows the memory location(s) are available for a new file. The file is recoverable until the memory addresses are overwritten with new data. The file can still be recovered after a disk format (possibly) unless the format proceedure sets all bits to 1 or 0. Quick format does not do this. Even if the file is completely overwritten there are techniques that may still be able to detect the magnetic residue from the previous information. This is of course an extreme situation but it has trapped quite a few criminals.

A file that has not been closed properly (or regularly) does not leave data that can be recovered.

Wonderful things, batteries !