A couple of years ago the kids discovered the benefits of our PVR, and suddenly (a) there was no space on the PVR, and (b) we could never find anything we recorded amongst the zillions of recordings of CBeebies, CBBC and CITV. And then we inherited an old Pace Twinview PVR from my father-in-law, who had traded up to a Humax 9200. So I set it up for the kids on “their” TV. This meant that they could record whatever they wanted, without filling up the PVR in the lounge. And for a fair time, life was good.
And then the Twinview started playing up, and eventually died. And suddenly I have three kids who want me to recover all the recordings that they’ve been making.
No problem I think – those recordings are probably just recorded directly off air as transport streams (.ts files) which I can easily transform (using ffmpeg) either into something like H264 video and MP3 in an mp4 container, which they can then watch on the PS3, or an MPEG2 file which I can then make into a standard DVD. So I say not to worry, I’ll fix it for them.
Which was hasty. Very hasty. And possibly a big mistake.
So I extract the hard drive from the PVR. Good news, it’s a simple 20GB PATA laptop drive which will fit nicely into my Thinkpad ultrabay. So I boot up Ubuntu, and do a quick “fdisk -l /dev/sdb” to discover that there are three partitions, all of which are unrecognised by fdisk. They are however flagged with partition identifier 0xE0, which after a bit of Googling turns out to be a completely proprietary filesystem, designed by ST microelectronics, called ST AVFS – presumably the ST Microelectronics Audio Visual FileSystem.
So currently I’m struggling to find a way to get at the data. It’s not possible to just mount the partitions, but it turns out that there has been some work done on some linux command line tools (TwinRIP) to extract the data from those partitions. However, the tools are at least two years out of date, supplied in binary form only, and no longer run under any of my Ubuntu installs (lots of problems with missing libraries). Now, it transpires that there is a GUI program to do much the same under Windows (TDU), which looks to be more recently updated, and (plus point) can directly produce MPEG output files. It will be interesting to see if that runs under Windows 7 RC, which is the only Windows install I currently have on my Thinkpad!
Update: And the results are in. The TDU program doesn’t work any better than the Linux one. And Windows 7 doesn’t want to talk (reliably) to the hard drive, whether mounted using my Thinkpad ultrabay, or a USB caddy. Worse, the author of TDU & TwinRIP has not published any source code, so there’s no chance of my doing anything geeky at this point, so I’ve declared defeat, and told the kids that their old recordings are now officially lost 😦
The only upside is that this gives me another free 20GB PATA laptop drive to play with, if only I can think of a use for something so small.