Storage: From film to optical
Jun 1, 2009 12:00 PM, By Collin Lajoie
Here’s a look back at the evolution from analog tape to modern digital servers, optical and flash storage products.
First NLE and video server
According to Schubin, the emergence of what could technically be considered the first storage and playout server system goes back to the evolution of editing and a partnership between CBS and Memorex.
“This company called CMX, which was a joint venture between CBS and Memorex … came up with a machine [the CMX 600] that even today is mind-boggling in its technology,” Schubin says. “So here we are at the end of the 1960s, and they have taken hard drive disc packs, which the discs themselves were about the size of a microwave oven, and the disc reader, or drive was about the size of a washing machine. So it's like sticking a microwave oven on top of a washing machine.”
These packs, Schubin says, could record about a half-hour's worth of black and white video onto disc drives and play them back. The offline editor's interface consisted of a light pen with a photo sensor that would allow the editor to click things off the screen immediately by touching it with the light pen, and that would create an edit decision list (EDL) in the computer.
“Well, the question was, how do you get that information over to the online editors? So CMX built an online editing system,” Schubin says. “This is in the era before floppy discs, so there was no way to transfer the information over to the computer in the online edit room except by punched paper tape, which was what teletypewriters used.”
Editors would then take these massive stacks of punched paper tape, he says, from the offline room to the online editor, and they would redo the edits on the actual content that was to go to air. And so the CMX 600 is widely recognized today as the first nonlinear editor.
Then in 1988, in line with the introduction of the first digital videotape recorder, now-defunct Editing Machines Corp. (EMC) had the idea of editing within a computer.
“So [what] they came out with didn't really catch on,” Schubin says. “But the following year, another company came out with the concept of nonlinear editing a little more thought out than the EMC version, and that company was called Avid. So that was Avid's first product.”
According to Schubin, the initial Avid product was an offline editor that would eventually take the place of many U-matic machines. And as technology improved, with the introduction of 8in floppy drives down to 3.5in floppy drives, the EDL was transferred from offline to online editing via disk. The quality of the Avid system then improved to the point that the online edit stage wasn't necessary, Schubin says, and that's when it went from being a nonlinear editor to a server.
But the Avid system, and similar systems from companies including Abekas and Ampex that eventually replaced the tape cart system in broadcast facilities, was being used mainly for production, according to Don Craig, CTO and co-founder of Omneon.
“Prior to 1990, the ‘servers’ were used strictly for production applications, and it was companies like Abekas and Ampex who made very special-purpose [systems]. They weren't called servers; they were just called disc recorders, recording relatively short clips that were used in production,” Craig says.
In the broadcast space, beyond production, it was time delay that helped popularize the use of video servers, according to Luff. “Time zone delay was actually one of the first things servers were used for. People were using it for delay of content for rebroadcast either on the same day or literally just a time zone delay — set an input channel recording and one hour later start an output channel playing the same video, and it becomes a continuous loop,” Luff says. “The earliest uses of servers had absolutely nothing to do with backup and had everything to do with cache, which time delay is really just a long cache.”
Craig worked with a company called Tektronix.
“In the early '90s, we started to see very compact and practical applications of JPEG2000-based compression techniques, and that coupled with the performance we started to see with the 3.5in tape drives was what enabled the [Tektronix] Profile to happen,” Craig says.
According to Craig, the creation of Profile came out of a merger between Tektronix and Grass Valley, because they were looking to build a platform rather than just an application. The first incarnation of Profile supported four channels of video for a total of 32GB of storage.
“It had to act like a tape machine, and it had to act like four tape machines in one — that was really the selling point,” Craig says. “So for the price of one tape machine, you could have four tape machines in one; the only catch was you couldn't remove the tape.” The fact that there was no removable tape didn't bother many broadcasters upon Profile's introduction.
Soon after the release of Profile, Craig left Tektronix to work abroad, but returned in 1998 to co-found Omneon. “Our initial goal was to do transmission servers along the lines of Profile, but with more comprehensive network I/O,” Craig says. “The notion with Omneon was we'd interconnect everything with a computer network, and the initial products were done with IEEE 1394, or FireWire. So [adhering to] the decisions in 1998, we elected to use Fibre Channel for disk I/O, we elected to use FireWire 1394 for video interconnect within the system, and we elected to use Ethernet for control and file transfer to these systems.”
Using FireWire, there was no connectivity limit on the number of devices that could send and receive video within the context of one server, according to Craig. And that's how Omneon set itself apart from Profile, which under Grass Valley was relaunched as the K2 line in 2005, adding some clustering features to the original design, Craig says.
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