Small External Digital Recorders
Posted 30 March 2011 - 02:30 PM
Also need to know about the availability of the recorders and their media. I know that KiPro Mini's are backordered, and SxS cards are scarce.
Posted 30 March 2011 - 02:49 PM
I used to build them, but I suspect my machinations can no longer compete with the integrated devices with custom ASICs.
Posted 05 April 2011 - 03:45 PM
Records lossless on SSD or normal HDD off the shelf.
It´s a kind of super iPad with SDI connectors - a mobile workstation that runs on Windows 7.
I did some writeup: http://frankglencair...essed-recorder/
Posted 05 April 2011 - 04:12 PM
Posted 06 April 2011 - 01:14 PM
Posted 07 April 2011 - 04:37 AM
Potentially-interesting but perhaps slightly offtopic technical analysis follows.
I know from experience that actually formatting video sequences into DPX files is quite a large processing load, if you do it in software, because the byte order on the SDI line is not the same as the byte order in any of DPX's many options - so you end up having to touch every single pixel. This is something that can take a low-power (a few watts) x86 processor uncomfortably close to saturation (where uncomfortably close is more than about 50% utilized in a hard realtime context like video recording). There is therefore a great temptation to treat the disk as a raw block device and dump the contents of the SDI input's frame buffer onto it sequentially, developing your own scheme for storing metadata. This is basically what Codex call a "virtual filesystem", or at least about half of it, where they've also written code to read their proprietary disk layout and dump it out to an external device as a standard format such as DPX or Quicktime.
There are other upsides to the raw-device approach, too - you get access to the absolute speed of the raw device with no overhead for filesystem, you don't consume any CPU time on filesystem or data wrangling stuff, and if done properly you don't have to touch every frame if you want to alter a chunk of metadata after the fact of recording it, which is a problem anyone recording DPX sequences will have. Renumbering a long take, for instance, can be quite time-consuming on an S2 box. On the downside, you have to ensure you've created some sort of reliability scheme to allow for power loss during a take, and some people would also see a proprietary filesystem as a way to lock people into one vendor, especially if they surreptitiously encrypted the data to frustrate reverse-engineering. I take an extremely dim view of this sort of shenanigans; that stuff's for the low end.
The downsides are that the disk is then not readable in any other device without special software (and writing filesystem drivers for windows is a minefield, so this is hard to solve in the general case). A device that does put DPX files onto a standard filesystem avoids this and there is no reason that an SSD "magazine" from such a device should not be readable on any computer with an external SATA port (which can be added to almost all current PCs with an adaptor cable costing a few dollars). This is one of the reasons why I find S2's technical approach unfathomable: they're using proprietary disk packs with a standard format on them, for the worst of both worlds.
The upshot of all this is that in the end, it doesn't matter if Codex's disk packs are proprietary or not - you wouldn't be able to read them on non-Codex gear anyway. You could theoretically read S2 packs on anything capable of reading ext3 disks that had an adequate SATA or SCA interface (depending on which version of the equipment), with a suitably configured adapter cable.