A contemporary production infrastructure must support multiformat production workflows for multiple distribution channels to a myriad of consumer devices. Traditional, non-networked production islands might get the job done, but with lots of blood sweat and tears, and a lot of time too. In this instance, information technology has in fact come to the rescue!
Continuing the graphics discussion begun in the previous "Transition to Digital" e-newsletter, the creation of GFX elements places a heavy demand on the broadcast IT infrastructure. Every system component, GFX card, computer operating system, network and storage, is pressed to optimum performance. These are not your networked, home PCs.
System components
From a user’s perspective, the GFX application is the most important part of creative process. But without a sufficiently engineered and reliable compute infrastructure, the creative process will be stressful and frustrating.
The beginning and end of many GFX production workflows are GFX cards. Blackmagic cards support SDI I/O, machine control, and are compatible with most GFX authoring applications. Nvidia technologies address all aspects of GFX computing, providing GFX processors, compression codecs, chipsets and high end GFX integrated computers.
Important features of any GFX card are SD/HD capability, operating system compatibility (Windows or MAC OS X), HD tri-level sync and RS-422 control. Be aware that to lay HD renders and animations to tape will require a consistent data throughput of 200MB/s to accommodate the 1.5Gb/s uncompressed stream.
Typical minimum system requirements for a GFX compute platform:
- Processor(s): Dual core or multiprocessor; 64 bit > 3.0GHz; 800MHz FSB, Hyper Threaded
- RAM: 4GB 400MHz DDR
- System hard disk: 7200RPM (minimum)
- Media hard disk: High performance RAID
- NIC: GigE
- Display: the native resolution of the video format (1920x1080 or 1280 x 720)
The internal computer architecture is important. This will ultimately determine performance. Do not overlook chipset compatibility with the applications you intend to use. It is a given that there are separate system and media drives running on discreet controllers.
Media networks
Islands of high-end GFX computers won’t be enough. An entire infrastructure must be designed for speed. HD uncompressed files are just too large to move around broadcast media networks efficiently. A 1280 x 720 60p canvas, with 10-bits per color, for RGB, is 1.66Gb/s data rate. Over Gigabit Ethernet, transfers will be at greater than real time rates.
Storage Area Networks (SAN) connect multiple servers to a centralized pool of disk storage. SANs use Fibre Channel technology for interconnections to compute platforms through fabric switches that operate at multigigabit speeds. SAN storage may be SATA with transfer rates at 150MB/s and for SATA II, 300MB/s. iSCSI links storage devices over a SAN and transfers data by carrying SCSI commands over IP networks.
Blue Arc manufactures high performance high availability (HPHA) storage systems where software packet analysis resides in silicon, i.e. dedicated chips. This allows consistently high throughput up to the theoretical design limit.
Top tier switches, such as those manufactured by Extreme Networks and Force 10 Networks are necessary to ensure mission critical operation. Links must be trucked to reach multiple Gigabit throughput and attain better than real-time uncompressed HD transfers.
Centralized storage also simplifies backup. A standard IT schedule of incremental and full backups can be run at appropriate times.
Render farm Perhaps the most stressing use of broadcast IT GFX resources is in an HD animation render farm. Calculating pixel by pixel, line by line and frame by frame is compute intensive and barely, if ever, attainable in real time.
In this system, the components, GFX card, computers (nodes), OS, applications, network and storage must work in total harmony in an integrated design for the farm to operate at maximum capability. Less time to render allows more animations and more sophisticated animations to be done, and then taken to air more quickly. Creative GFX artists may even create a unique, differentiating effect that will garner more eyeballs, and maybe even create a buzz!
Somewhat akin to clustered computing, render farm implementation is a configuration capability sometimes innately supported by a GFX application. If not, dedicated middleware must manage the job, parsing the file into frames, assigning them to nodes for rendering and then reassembling these new frames into a file. A centralized SAN, rather than local disk, can reduce render time dramatically. Six-hour renders on a single machine can be done in less than an hour using a farm!
When implementing a render farm, the animation workflow must be considered. There is a trade off between frame render time and file transfer to the farm. The requirement to do very small and short animations may be more cost effectively accomplished with local machine renders. But for big animations, 30 seconds full screen HD, the less than real-time file transfers to the render farm are more than offset by rendering speed.
Issues Pay attention to the interaction of your GFX application and GFX card. How does color space interact? For example, if GFX are created using full-scale (0-255, 8-bit) values, will your GFX card convert them to legal ATSC or NTSC color space?
If your system will be used to take GFX to air, be sure that it will genlock to house sync. Will the application or GFX card be in control of video timing? This should be clearly established during system configuration and testing.
Consider configuring your GFX computers in a maintenance mode, where update packages only install patches for know bugs and do not install new features. This promotes system stability.
Security is important. Broadcasters have been hit by viruses and worms. Indiscriminate moving of GFX files using detachable media, such as drives, USB sticks or DVDs, offers an easy entry point into your infrastructure. A virus scan alone will not be enough.
Turnkey solutions Designing high performance GFX systems requires more than traditional IT skills. Should you build your own machines? If your staff does not include experienced IT architects, you will have to rely on either a vendor or a systems integrator.
If you buy an integrated package from HP or Dell, it will be a certified system and support should be part of the deal. You will avoid the headache of getting the GFX card, OS, applications and computer to work reliably together. Have a detailed test plan and stress the machine to death!
SGI and Alienware build high end computer systems for GFX applications. The Adobe OpenHD Alliance provides After Effects certified turnkey systems delivered by 10 member companies.
A glimpse into the future *Grid Computing
*The Grid Report
*HP offers render capacity on demand and has worked with DreamWorks on numerous film projects.
*Two articles about storage switches:
Network World
eWeek
*Holographic Storage
*Holographic storage was discussed at SMPTE last year and Turner.
Emerging technologies, such as grid computing, holographic storage and storage switches, may be naturals for graphics environments. (See sidebar).
Bang for your buck
As with any large capital investment, ROI will be an influencing factor in determining the constraints on GFX infrastructure engineering. A reliable, high-performance HD render farm and/or GFX environment will be expensive. Consider all possible benefits, both in dollar amount and in intangible process improvements. If animation is outsourced to boutiques, $500K invested in GFX resources represents 5% of an external yearly expenditure of $10 million. If this allows 10% of those animations to be done in-house, with 10 graphics artists and animators at $50K per year, the GFX infrastructure pays for itself in a year or so.
Once a decision has been made to move forward, cost cutting can lead to hidden expenses. TCO must be considered. If insufficient compute power, switch performance and storage capacity are purchased to save a few dollars, or because of the failure to adequately engineer the infrastructure, you will spend far more on in-house support, vendor site visits for troubleshooting and downtime for GFX production.
Pennywise and pound foolish
Don’t let the expense of installing high end GFX and animation systems stop you. Going cheap will only lead to trouble. The system will never operate optimally and production schedules will be destroyed.
Do it right. Be sure to look at your final product on different displays. Test different conversion scenarios. Let the designers have the capability to route to a variety of displays.
A properly engineered GFX infrastructure, used by informed, talented GFX artists produces elements that are a critical part of a broadcaster’s image. Graphics can be overdone or underdone, but they must be done. Like it or not, high-end graphics must be produced to remain competitive. But the differentiating point will be the quality, sophistication and tasteful integration of GFX into your programming.
