DVR unknown recording format

[zilog jones]

I have a Walker WP645TS-HD set top box, a DVB-T/DVB-S2 combo box which I believe is manufactured by Vestel (sold by Walker in Ireland).

It has a USB recording function, but uses some odd file format that I am having no success trying to play on a PC.

The files and directory structure looks like this:

RECS
|
|-2012071100013501.ifo
|-2012071100013501.keyinfo
|-2012071100013501.rec.nav
|-2012071100013501
|
|-chunk.0
|-chunk.1
|-chunk.2
|-etc.

The "chunk" files look like where the actual data is stored. The first one is always 0 bytes, then each one is 64 MB until the last. I've tried renaming these to .TS, .VOB, .M2TS and some other common formats but was not able to play them in MPC or VLC. The recording are a variety of MPEG-2 SD and MPEG-4 HD.

Has anyone experience with files like these? Is there any software I could try to extract useful streams from them?

[Ghitulescu]

Considering that an HD programme has at least 4GB, I would correctly assume it will fill 1000 chunks of 64MB each?

Anyway, have you tried to record only one show, and see whther by binary concatenating them you'll obtain a valid file?

If not, then I believe you met a DRM issue - many "recorders" that are able to use external drives are legaly forced to employ various techniques NOT to allow the use of the recorded data outside its own gear (even identical models).

Have you tried a "recovery" software? One that "guestimates" the type of the assumed broken files?

[zilog jones]

Considering that an HD programme has at least 4GB, I would correctly assume it will fill 1000 chunks of 64MB each?

I have a recording of about 45 minutes and there's 53 "chunk" files, totaling 3.24 GB. Not sure where you got the 1000 from, 4 GB would be 64 files :)

Anyway, have you tried to record only one show, and see whther by binary concatenating them you'll obtain a valid file?

How would I go about doing this?

If not, then I believe you met a DRM issue - many "recorders" that are able to use external drives are legaly forced to employ various techniques NOT to allow the use of the recorded data outside its own gear (even identical models).

This STB is designed primarily for FTA services so I don't know why they would do this, but it probably is pretty generic hardware...

Have you tried a "recovery" software? One that "guestimates" the type of the assumed broken files?

I have no experience with software like this. Could you name some examples? Preferably something free...

[Asmodian]

binary concatenating is as easy as:

copy /B file1.ext+file2.ext file.ext

might get more annoying doing 53 of them.

Give it a try and if it works and if you need help writing a batch to concatenate all of them let us know.

edit:
just curious but how large are these?
2012071100013501.ifo
2012071100013501.keyinfo
2012071100013501.rec.nav

"keyinfo" makes me think there might be some encryption.