Media files typically have a header at the beginning of the file and sometimes a footer at the end. The data goes in between. Sometimes if either the header or footer are missing, they can be reconstructed by creating a working file of the same type and copying the hex codes over.
You usually have to be pretty accurate or you can get corrupt parts of the video as it decodes the data from the wrong start point.
All this is done using a Hex editor.http://ridiculousfish.com/hexfiend/http://www.versiontracker.com/dyn/moreinfo/macosx/10658
You'll be lucky if the file actually has any data in it though. It may be filled with zeroes when you open it in one of those programs - if so, it's not recoverable as you don't have any data. When a file is being written, it opens up a file reference. If it doesn't close it properly, it can flush the entire file. This is just the way that computers work. Even with resumable downloads like torrents, if the computer crashes during a 2GB download, it can easily reset back to zero instantly - the file size stays the same, the data is just zeroed out. Because it's not allocating new space, it can do this very quickly.
This is one advantage that tape recording still has over digital recording. It simply can't destroy any of the information that's already been stored. If you'd split the digital recording into a new file after every couple of minutes, you would only have lost at most 2 minutes of footage. It does become a bit of nuisance to join them up again though and you can get dodgy frames in something like HDV as it's not an i-frame compression like DV, DVC Pro or AIC.
Instead of doing it live using a computer where anything from a crash to a power outage can affect the capture, maybe use one of these:http://www.emedialive.com/Articles/R...ArticleID=8681
You then record to both hard drive and tape plus due to the filesystem limitations, it has to split the files into 2GB segments. They say it's inconvenient but 15 files isn't that bad if it saves your ass. Plus you can recover any of the broken files from the tape as a last resort.
You get standalone models that connect to any camera like the Quickstream and Firestore drives. Quickstream have a solid state model too that does HDV.
Either that or capture live to a laptop with a battery backup. The portable recorders take power from the camera battery.