Recovering recordings from dead Pace Twinview PVR

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 However, the tools are at least two years out of date, supplied in binary form only, and no longer run under any of my Ubuntu installs (lots of problems with missing libraries).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.

Smaller is better?

Work provide me with a laptop for business, changing them every three years or so. I’ve had a succession of IBM Thinkpads, which I have to say are truly the Rolls-Royce of laptops. Relatively compact and portable, stuffed with features and the kind of build quality that allows them to survive years of abuse (mine have travelled all over the world with me). My experiences with them have been exemplary … until the last few years, when IBM sold the Thinkpad business off to Lenovo. The last couple of machines have not been so great. My top of the range T40p needed 3 motherboards in as many years. My current T60p has already had 2 motherboards, a fan and a heatsink assembly in two years. And now the screen (a rather nice 15″ 1600×1200 job) is showing lines of dead pixels that probably indicate either the LVDS connector is failing, or I need yet another new motherboard. In addition Thinkpads seem to have been steadily growing. My last two machines have not fitted into my “old faithful” laptop bag, requiring a bigger heavier bag to carry them in.

So recently I found myself wondering why I needed a machine with 2 x 2.16GHz processors, 2GB of ram, and a 1600×1200 pixel 15″ screen. Fundamentally I do the same stuff on this machine that I did on my old Thinkpad 600 some 10 years ago. I do email. I browse the web. I use IM. I follow some (real NNTP!) newsgroups. I create documents and I read documents. I do presentations. I occasionally print stuff. So why do I now need the above monster specification, when I used to get by on a single 300Mhz processor, with 384MB of ram, and a 1024×768 13″ screen? And the more I thought about it, the less I could understand it. All I’ve done is adopt a much bigger and heavier machine, that runs a lot hotter, to do the same stuff. The bigger machine isn’t actually allowing me to do anything faster … I still think at the same speed. In fact, in one area my performance has actually decreased – I actually walk a lot slower with it because it weighs so much.

So at Christmas I decided to have my own personal “grand challenge” – to see how small a machine I could get away with to do my job. So I went out and bought my first ever laptop – an Acer Aspire One “netbook”. I got the one with 512MB of ram, and a 120GB hard drive. Cost me 200GBP here in the UK (I know, they’re a LOT cheaper in the USA – we get screwed on computer stuff here).

A day playing with the preloaded Linpus Lite linux (aka hacked Fedora 6) convinced me that while it was set up to be a foolproof computing appliance for the computer-illiterate, I needed something fuller-functioned. So after a little bit of fiddling with gparted, I now have the Aspire set up to triple boot any of (a) the original Linpus Lite, (b) Windows XP SP3 and (c) Ubuntu 8.10. Ubuntu will be my OS of choice, with Windows there purely for the odd work application that I have to use that isn’t supported under Linux. I kept Linpus purely to compare my performance tuning of Ubuntu to the stock preload.

To Ubuntu I added Thunderbird, Lotus Notes and Sametime (our corporate-standard groupware) and some VPN software. I then added OpenProj, Freemind and Dia, and upgraded the OpenOffice install to v3.0. And to my astonishment, in the last month I’ve needed nothing else.

There have been some teething problems though.

The first problem I experienced was that on Linux, Lotus Notes is implemented as an eclipse plugin, so unfortunately by the time it’s loaded there’s very little left of the 512MB of ram. I gave up after a couple of days, and sprang for another 1GB of ram, at another 13 GBP. Installing it required the complete disassembly of the Aspire … but in actual fact only took about 20 minutes with a set of jewellers screwdrivers. This maxes-out the memory on the Aspire One (at 1.5GB), but I now seem to have memory to burn, even when I have all my applications open at once.

The second problem is that as a long-term thinkpad user, I’m used to having a trackpoint (the little red “nipple” embedded in the keyboard) for moving the cursor. Compared to the control that that provides, a trackpad is a hopelessly painful experience. Fortunately I already had a Logitech bluetooth mouse (a V470), but unfortunately the Aspire One doesn’t come with internal bluetooth. So I had to add an external USB bluetooth adaptor. I imported a USB Bluetooth 2.0 EDR micro-stick from Hong Kong for 6 USD which resolved that problem, and is actually small enough to be left permanently attached, though longer term I’ll probably solder the internals of one to the motherboard somewhere.

Other than that, it’s proving a remarkably solid little performer. The keyboard is a little cramped, but just about big enough to almost-touch-type on. The screen is painfully small, but with multiple workspaces and compiz-fusion doing its thing, you can work around that. And I have external monitors at home and at the office, so it’s only really a problem while travelling anyway. If I have a lot of stuff going on then some applications can be a little sluggish, but even then it’s not problematic … just noticeable.

Boot times for standard Ubuntu were very slow compared to the preloaded Linpus lite, but a custom kernel tailored to the Aspire One has got that down to about 25 seconds, which is faster than standard Ubuntu boots on my T60p. Still not as fast as Linpus though – which is up in about 15 seconds. Battery life on the standard 3 cell battery is only about 2:20; a high capacity 6 cell 3rd party battery should take that to about 7 hours but for my working patterns that’s unnecessary, and would start to add to the weight and size again.

Which leads us to the question of do I declare the challenge beaten or not? I’d justified buying the Aspire One on the basis that if I couldn’t live with it, I’d simply give it to one of my daughters, as I figured it would be fine as a first machine for school-work etc. Well, at the moment I’m not prepared to give it up. It does everything that I need – just, and no more. In fact, these Aspire Ones would be great for my daughters, and the only thing holding me back from going out and buying them a pair is the faint hope that we may see some netbooks built around NVidias ION platform this year.

Replacing the Intel 945GSE chipset (which seems to be based on 3-4 year old designs) with the NVidia GeForce9400 chipset ought to result in a stupendous graphical performance hike for no increase in power consumption. The only question is, will anyone do it? The problem is that it makes low-end netbooks compete with mid-range laptops (problematic for the manufacturers), and Intel is sure to price the Atom/945 combination in such a way that its almost as cheap to take the pair as an Atom on its own – which would stuff any chance that Nvidia have. Will be interesting to see how it works out.

All change …

Due to poor support for my laptop hardware, I’ve been lagging behind the times recently, and I’ve not moved forward from Ubuntu 7.10 since I installed it about a year ago. And that’s despite the arrival of 8.04 which was supposed to be the long term support version, with lots of stability updates.

So imagine my surprise last week, to discover that when I tried a trial fresh install of Ubuntu 8.10 (which is all about new function, not stability), almost every issue I had on 7.10 had been fixed.

So, I now have hardware accelerated graphics on my Mobile FireGL chipset (and hence Compiz support), the ability to switch the external VGA output on (so I can actually present from this laptop under Linux!) and working suspend (and resume afterwards). And the icing on the cake is that my wireless works properly in our corporate environment, for the first time ever. So as of now, I’ve switched over to Ubuntu 8.10 as my main OS, and I’m upgrading to the latest versions of all my applications as we speak.

Which brings me to this post, which I’m currently making through a new tool, called gnome-blog. It’s a pared down to the minimum, extremely simple to use, and completely integrated into the Gnome panel blogging applet, that’s never more than a click away.

Hopefully it may get me posting a little more often.