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By William Van Winkle |
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Solving Storage In most discussions about digital video, hard drives are often only mentioned from a capacity standpoint. Everybody knows that video chews through a ton of megabytes, so the more capacity for storage the better. But there's a lot more to video and storage than capacity. DV and HDV video, the two most common formats in today's consumer to prosumer digital camcorders, both have a constant data rate of 25 Mbps. You'll often hear that modern hard drives have no problem keeping up with this kind of throughput. And that's true...to a point. A drive like Seagate's Barracuda 7200.10 boasts a maximum sustained transfer rate of 78 MBps. Even the dated Barracuda 7200.7 sported a maximum sustained rate of 58 MBps. However, the 7200.7's minimum sustained rate is 32 MBps, or 256 Mbps. The average consumer is not going to try to overlap 10 DV clips in a single render to flood his scratch disk's bandwidth, but a prosumer might.
Moreover, you have to figure that there could be other applications in the system that could pop up with disk bandwidth needs of their own. Having a point-to-point technology like SATA reduces many of the problems seen with parallel ATA, and adding in a second current-gen SATA drive configured in a striped RAID with the first should add all the bandwidth any consumer could ask. Alternatively, you should consider how many concurrent video streams might be reading from a single hard drive. "If you're transferring video from a drive to one monitor, there's absolutely no advantage to having an enterprise drive over a desktop drive," says Willis Whittington, senior product marketing manager for the enterprise compute business at Seagate. "But if you've suddenly got 20 clients out there all looking at that same video, then the enterprise drive's performance is much higher when it comes to seeking time. You can get to the different points on the disk a lot faster so you can handle more clients." This might be an important consideration when equipping a small hotel or large bed and breakfast, for example. And conceivably, you might find clients with applications requiring them to run multiple videos concurrently on each station. Just when you think you can guess what your systems will and won't be used for, someone will surprise you. To this point, we should be careful not to assume too much about consumers and small businesses. Sure, mom and pop may only need one or two video layers for their home movie projects, but some buyers may turn out to be like Shane Carruth, who wrote, directed, produced, and edited the mind-bending time travel movie Primer, which went on to win two awards at the 2004 Sundance Film Festival. Carruth made Primer in his spare time on one desktop PC primarily using Adobe Premiere and After Effects, with a little help from Photoshop and 3ds Max. He made the movie on a budget of $7,000, and the project took two years to complete while holding down a regular job. Carruth shot the original footage on Super 16mm film, but in the present and with a little more budget, a similar would-be film maker would likely want to have an all-digital workflow and shoot in high-definition. HD can mean different things to different people. Only three years ago, HD televisions were considered to be sets based on 720 lines of resolution. Today, that number is up to 1080. Now consider that DV entails 480 lines and HDV uses 1080, but that's 1080 interlaced, meaning each frame only contains half of the image. Ideally, you'd want 1080 progressive, wherein each frame contains the entire image. Moreover, HDV uses MPEG-2 compression. We all know from DVDs that MPEG-2 can look decent, but you still lose a fair amount of subtlety. Because of this, digital video purists will want to shoot with an uncompressed format. Today's serious videographers and film makers of any type want an all-digital workflow above the level of 1080i HD. Much contemporary professional work is now being done in 2K, meaning 2,000 lines of resolution, and this is quickly transitioning into 4K. To put it into perspective, 4K is 8 megapixels per frame and a massive 6 Gbps in bandwidth, or over 850 MBps. Today, digital projectors in cinemas show images in which individual pixels are clearly visible. At 4K, it will be like looking through a window out the back of the theater. "Video editing, like games, hits all the system bottlenecks, including storage," says Adobe's Dennis Radeke. So an unequivocal yes to faster storage and more of it. If you want to move up to real-time—two or more streams of video playing simultaneously—the requirements start to go up. If you move up to a format that has more data per stream like DVCPro HD, 50 Mbit MPEG-2, XDCam HD, etc., those requirements go up again. Finally, the frontier now is realtime, uncompressed HD editing, which is 165MB per second per stream. Take two streams along with all your graphics and other stuff and you've exceeded the bandwidth of SCSI Ultra-320. For this, you're going to need some super fast and large storage." Which brings us back to the discussion of enterprise drives—but first we need to make a distinction. There are two ways to look at video. You can have relatively simple video streaming, wherein all you really care about is the consistency with which data flows onto and off of the platters in a sustained, linear fashion. Then you have editing, wherein (for professionals) you need maximum control over how data gets written and processed. In both cases, as Seagate's Whittington explains it, error correction can be critical. "With a regular drive, if the information that comes off is found to be in error when the drive checks against its own ECC, the drive will discount that data and go back to the drive and reread it. It'll keep doing that, changing parameters all the while, to optimize the readback until it reads all the data. Once that's done and the data is correct, it gets sent to the host and then to your screen. On a desktop drive, that process can take more than 30 seconds. And during 30 seconds, there's a lot of data coming in that you have to buffer. And if your buffer isn't big enough—and in 30 seconds it wouldn't be—then you lose it, which means your screen goes black for a while until the data can resume. If you use a high-performance drive, data recovery is a minimum of 2.5 to 3 times faster, and possibly a whole order of magnitude faster, which means no blank screen and no lost data."
Obviously, a buffer underrun cause by error correction will create a jarring, unacceptable gap in any streaming recording or playback session. This is why Seagate modified the Barracuda desktop drive into a far more error tolerant version called the DB35, which is primarily slanted at consumer DVR applications, although resellers should keep the model in mind when designing corporate live recording and video presentation systems. But as we've seen, some multi-stream applications can overload desktop SATA drives, and HD editing with multiple layers can slam a regular drive into whimpering submission. SCSI and SAS drives also feature advanced error correction controls, but unlike with SATA, users can optimize drive settings through the use of a small, free utility. Why pay all that extra money for a SAS drive when the DB35 features similar error handling? Honestly, there isn't much difference in the actual head-to-platter transfer rates between SAS and SATA drives. However, in the absence of much seeking, drive bandwidth is essentially proportional to the rotational rate of the spindle and diameter of the disk. Heads cover a lot more platter real estate at 15,000 RPM than at 7,200 RPM, so more data can be written or read in the same time. High-end SATA drives like the Western Digital Raptor WD1500ADFD run at 10,000 RPM, but use a 3.0" rather than a conventional 3.5" platter, so you don't get the same boost at the platter's outer edge. Neither does the Raptor supply those error correction benefits. No, the only way to go when video performance is critical is a SCSI or SAS drive, and given current market trends, we really mean SAS unless you're trying to support an organization's existing technology infrastructure. To improve digital video performance beyond the bounds of a single SAS drive, the obvious next step is to move into a SAS RAID. Adaptec and LSI dominate this adapter field, and while we have some terrific experience with Adaptec's management software, the key thing to remember is that discrete SAS RAID is going to deliver markedly better results than an on-board, integrated SAS solution that leans on the CPU for RAID computations rather than a discrete storage processor. Moving to a four-drive striped array will increase bandwidth by almost a factor of four, but be sure to note that this applies to reading. Writes involve a lot of extra computation overhead. To be sure, striped writes are faster than single-drive writes, but the process doesn't scale as linearly as reads. Additionally, it doesn't always make sense for digital video RAIDs to be based on SAS.
"We almost always go with internal SATA RAIDs," says Ashley Guy, president of video system reseller Guy Graphics. "They're cheap, they're fast, they're fairly reliable. From a performance standpoint, a guy might want just a RAID 0. If you need to add data protection, go RAID 5. You don't really need to go beyond that until you reach uncompressed video. But even then, we're doing machines for uncompressed HD editing using 15 SATA drives RAIDed together." Most towers can only accommodate 10 or so hard drives, and with SATA capacities now topping out at 750GB per drive, the maximum amount of storage one might fit in a full tower might be 7.5TB—if you have enough drive ports. Recall Radeke's comment about uncompressed HD editing involving 165MB per second per stream, and suddenly 7.5TB doesn't seem so big anymore. To come up with a 15-drive SATA solution likely entails installing a SAS controller and feeding to an external drive enclosure—a perfectly cost-efficient solution that can scale up in performance to SAS if and when the need arises. Of course, some resellers find that clients are willing to go with SAS from the outset for any of several reasons. "If you're going to be working with extremely large files," says VP Technologies' Yoav Chutnoff, "I think that's the main reason to go to SAS. When customers are working with 100GB, 200GB files, which isn't all that large per se, they may just keep it on the station using SATA. But I haven't seen too many people who get higher-end solutions working with such small files." The Software Side Of course, the whole point of pounding out a perfect DV hardware configuration is for the sake of running DV software more effectively. As promised, we're not going to veer off into a wild, in-depth software tangent, but we wanted to spotlight a couple of items that illustrate the benefits of following some of the above hardware guidance and might give you some ideas on what sorts of applications and usages to present your customers. Your starting point, of course, is Adobe Premiere Pro 2.0, the industry's de facto video editing software. Consumers can fall back on Premiere Elements 3.0, a simplified version of the master editor that still contains about 80% of the Pro version's total functionality. At only $99.99, Premiere Elements is a steal, and the $150 bundle with Photoshop Elements is a must for any consumer who wants to go beyond chimp-level editing but doesn't want to be overwhelmed with a staggering learning curve. Premiere Pro has that learning curve, and the wealth of books, tutorial videos, classes, forums, etc. that revolve around Premiere and After Effects (the motion graphics and FX adjunct to Premiere) is gargantuan...and necessary. It goes without saying that you and your sales staff should at least be fluent in Adobe's basics. This need is magnified by the fact that you probably won't be selling Premiere by itself. Rather, if you're selling a solution-oriented system, you'll probably be pushing Adobe's Production Studio, which includes current versions of After Effects, Premiere, Photoshop, Dynamic Link, and Bridge in the Standard version. For another $500, the Premium version adds Audion, Encore, and Illustrator. Any decent treatment of Production Studio would be another cover story unto itself. Suffice it to say that the package will take users on an end-to-end journey from content capturing through granular editing into post-production and finally out to export for any medium from low-bandwidth Web streaming to blue laser optical disc. This process involves graphic design, image retouching, audio waveform editing, disc menu construction, and so much more that it's like trying to take in the Grand Canyon at a glance. In a word, it's impossible. It takes months just to explore the package's main pathways and years to know it intimately. Despite Production Studio's immense scope and power, though, there are still many ways in which the suite can be improved upon by third parties, and this is where your reseller value kicks back into play.
Longtime After Effects users know that rendering slaughters CPU resources. (This is why After Effects now leans so heavily on OpenGL acceleration.) This has always been part of the reason you throw as much processor performance into a DV workstation as possible; Adobe chews up as much as you can throw at it and keeps wanting more. Not only does CPU speed largely determine overall rendering duration, that rendering period is time in which the system is unable to perform other tasks because there's no processor bandwidth left. Enter GridIron's Nucleo Pro (www.gridironsoftware.com/NucleoPro). In a nutshell, Nucleo Pro institutes a background render queue for After Effects. This means that Nucleo Pro takes over the job of assigning how system resources get applied to After Effects render tasks. Maximum Mode will make After Effects the priority on all CPU cores for times when every minute counts. Optimum Mode leaves enough overhead for other applications so that the user generally won't even feel the impact of renders running in the background. GridIron goes further by optimizing how After Effects utilizes RAM resources, then aggregates disk writes into a single operation in order to alleviate storage bottlenecks. But wait, there's more. Nucleo Pro also introduces the Spec-Preview and Spec-Render functions, "Spec" meaning speculative. If you remember speculative browser caching from the days of dial-up, you'll get the idea immediately. Whenever one creates changes in an After Effects project, Nucleo assumes that the user will want to soon preview and/or render those changes, so it starts to do those processes in advance of the user requesting it. This can drop actual preview/render times precipitously and put a ton of project efficiency back into users' hands. And talk about a way to leverage hardware investment. Nucleo Pro makes sure that the CPU and RAM resources customers pay extra money for aren't just sitting around idle. "For our stuff, what you really need most is RAM," advises Robyn Paton, manager of marketing for GridIron Software. "We'll eat up as much RAM as you can throw at our software, because that's what we use to aid in the processing. We're running separate instances of After Effects on each one of those CPU cores, and each one of those software instances need RAM. It'll take as much as you can give it, especially in 64-bit. If we can speed effects rendering up, that's always a good thing, because the more time that you have to work on effects, the better effects you get in the end." From a system resources standpoint, with Nucleo Pro speed is good but size is better. On the other hand, too much hardware can in a sense act like a render farm in your machine, with processing loads getting broken up, crunched across an array of resources, and then recombined for final output. According to GridIron, though, small video jobs may suffer in the face of an overabundance of hardware resources because they get too spread around, there's too much effort spent recombining, and overall efficiency drops. So before you go all out to recommend DV stations with eight CPU cores and 32GB of memory, make sure with some hands-on testing that your customer's extra money will be well-spent. On the other hand, while GridIron maintains that there's still a place for the likes of Pinnacle and Canopus rendering cards depending on the project and industry, the $495 spent on Nucleo Pro may just save the user several times that amount by removing the need for such specialized hardware. Of course, there's more to DV than editing. First, you have to capture video, and while there's plenty to consider on the camera side, one of the biggest unsung problems is the process of moving footage from the camera to the PC. As anyone with even a consumer camcorder knows, the traditional method entails capturing footage to a tape in the camcorder, connecting the camcorder to a PC after shooting, then playing back the footage via FireWire or some similar method into a video capture/editing package. One of the advantages of migrating from analog to DV (and other digital formats) was that DV automatically segmented a tape of footage into clips corresponding to each start and stop of the capture session. (With analog, the footage needed to be fed into the PC in its entirety, then the user either needed to create clips manually or have the capture/editing utility perform automatic clip creation based on detected scene changes.) But even with digital's advantages, the process of moving from shooting into editing is cumbersome, and with DV Rack from Serious Magic, resellers can step in with a relatively little-known way for end-users to become more productive by saving substantial time in a project's early stages. "This is the first package designed for shooters, the people who go out and shoot video," says Karl Soule, product manager, professional products for Serious Magic. "In traditional video workflow, everything is linearly stored to the tape. There's no easy way to go through and name clips, no easy access to one particular piece of video. In most cases, people end up shooting on tape, going back to the studio, and then spending at least an hour of time going through an hour of footage to find out what was good and bad. With DV Rack, the whole idea is to let you record right to the hard drive through the FireWire connection. Each time you shoot, you generate an individual clip." Teamed with a 1394-enabled notebook, DV Rack frees users from shooting through an eyepiece. Now, they can have a 15" or 17" viewing screen. Moreover, by adding on a USB or FireWire external hard drive to the notebook, shooters have access to a storage base of 500GB or more for raw footage clips, all of which is accessible in realtime. According to Serious Magic, DV Rack does most of its work by spooling into a buffer in system memory. This eliminates any chance of hard disk congestion impacting recording performance. In fact, DV Rack works just fine even recording DV footage to a 4,200 RPM drive. This isn't to say that users can throw away all of their tapes. Now, though, the tape can act as a backup device, not the primary recording medium. The idea of recording direct to disk is nothing new. Analog systems have been able to spool straight to hard or optical media for years, and even Premiere supports such camera-to-drive functionality. The difference is that no prior product has sported this level of feature depth, usability, and convenience. "Until now, there was no easy way of going back and scrubbing through a clip," says Serious Magic's Soule. "The waveform monitor and vectorscopes, which are used for like double-checking your video and making sure that you're getting the best possible image out of the camera, using the lighting correctly, and so on are nonexistent. Because you don't need them in the edit bay. You need them out in the field when you're shooting. The whole goal of DV Rack is to provide all the tools necessary to make sure you're getting the best possible image out of the camera and then save all the time of recording to tape and then transfer that from tape to the computer."
One of the hot features in the new version of DV Rack is onionskinning, which is very useful for stop-motion animation or other scenarios in which near-perfect alignment between shots is desirable. With onionskinning, you take a very thin layer of one video clip and put it over the top of the camera's current output so you can see the new shot through the previous one and line them up correctly. A common editing problem that onionskinning solves is the size of the subject. In the finished video, a subject will be talking, talking, and then—pop! Suddenly, he'll look three inches taller and bigger overall because the camera position or zoom amount changed between shots. Or there's the interviewer's favorite, the jumping lapel microphone that appears on the left before lunch and the right afterward. In the DVD extras for The Lord of the Rings, there's a story about how one very emotional scene had to be reshot multiple times because of a costume difference between shots, one shot was out of focus, and so on. With onionskinning, such continuity problems are greatly minimized, lowering production costs and increasing the project's final quality. "There is a special module in the software that's designed for beginners called the SureShot module," says Soule, "and it walks you through with a wizard and a little bar, saying like to adjust the iris on your camera until this bar is touching this red and this green area, or adjust focus until this bar gets as big as it can be. We put that in there for people who don't know what the scopes are."
Of course, one of the great reseller facets of the DV Rack proposition is that not only do you get to add a whitebook into your DV solution, but you can swing in with any number of external storage products. Premiere and After Effects are all about functionality, and you should have them in your lineup if only because they're the default apps for small business video. But Nucleo Pro increases the value of your hardware, and DV Rack not only adds more hardware opportunity but also simplifies the experience your hardware is supporting. As such, these titles are very complementary to your hardware efforts. Take this as a guideline when configuring a full DV solution for clients who may not have a clearly defined set of video applications in mind. Lights, Channel...Action! Digital video is equal parts entertainment and tool, and regardless of which side of that fence you and your customers sit on, the fact is that everyone, regardless of audience, is now embracing the trend. Your digital video pre-sale process needs to begin by showing customers how much more video can do for their operations. In many cases, video adds a whole new level of opportunity for your customer to reach his customer in a way that is more unique and effective than anything he's done before. If the customer already has Web staff on hand, blending in video is a simple matter if they have got the right tools. If the client has graphic design people in-house, it's not a large step to move from static images to dynamic action. Those who do Flash are already half-way there; it's only another step or two into the digital video world. Many customers may not be up to the level of realtime HD editing yet. That's fine. But don't let them make the mistake of dodging HD altogether. You've seen the difference between SD and HD even at the local electronics retailer or movie theater. Go find a decent-quality 50" or 60" display running 720p or (even better) 1080i content and see if you aren't blown away. If so, then rest assured that others have the same impression, which is why digital signage, presentations, and other visual forms of communication will increasingly shift to those resolutions. High-def is the next norm, and if your customers are producing content in anything less, their projects are already destined to be dismissed. One can always scale down from high-def into lower resolution formats as needed; you can't go the other way and make pixels out of thin air...not and have it be presentable, anyway. Starting in HD is worth every penny. You won't be selling in the digital video realm for long before realizing that, like with consumer electronics, some gear isn't accessible to ordinary resellers through distribution. Some cameras, such as Canon's H1, require you to be an authorized reseller in order to purchase them. So your next step is to find a local pro camera shop that is authorized and partner with it. You may only make a 10% commission on that particular hardware item, but at least you get to remain the sole point of contact for your client. There are myriad other ways to add value, as well. One might be to guide your clients through the maze of selecting an appropriate host for their online video content. (If the provider offers you a finder's fee, even better.) Another could be to configure the morass of options menus present throughout the Adobe Production Studio suite to fit your client's needs during the installation phase of the system build, everything from acceleration settings to audio format defaults to the selection of royalty-free content sitting ready on the local hard drive. Point your clients toward as much digital video education as possible, because the more their expertise grows, the sooner they'll be back needing to scale up on speed and functionality. In fact, for customers with less experience, you may even want to include copies of Adobe Premiere Pro 2.0 Classroom in a Book ($32.99 on Amazon) or Adobe Premiere Pro 2 Bible (also $32.99) and build the cost of the text into your bill of materials. It goes without saying that if you've got a digital video whiz on staff, you can build some community credibility and another sales channel by hosting your own classes. And remember: Digital video is no longer a niche; it's a part of our everyday life, both personal and business. There are few doors that video can't open if you market creatively, and among existing customers the odds are that you can open plenty of doors still wider. Most of your competition has yet to seize on this angle. Let digital video set your sales in motion. |
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