Creating and transmitting 4K content requires more storage, higher bandwidth and more computing power than HD. Image: anandtech.com
Is your facility ready for 4K? If not, then listen up because you will soon have some tough decisions to make, the first of which involves storage and bandwidth.
The production community has always led when it comes to advancing image quality. Always pushing the limits, asking for better pictures, immersive audio, higher highlights, deeper blacks. At the same time, I’ve never met the broadcaster who was anxious to tear up the TV station to support the latest innovation. Broadcasters tend to be more risk adverse for a variety of reasons.
Neither approach is good or bad, the choice has much to do with how long the equipment must last, continuity of service and budgets. But on the broadcast front, a revolution is about to take place, all centered on ATSC 3.0. One of the advancements that the new broadcast standard will support is 4K imagery.
Consider the infrastructure
Assume for the moment that producers will supply 4K content to TV stations. It then becomes necessary for the local affiliates to process, route, brand and transmit those images. What is needed?
Much like we saw with the evolution from SD to HD, 4K is influencing consumer expectations for high-quality content. And, like HD, 4K requires upgrades within the media workflow.
The migration from SD to HD was less disruptive than the move from HD to 4K will be because SD images can be easily up-scaled to HD just prior to transmission. However, it is not practical to up-scale SD or HD content in attempt to create acceptable 4K imagery. Once 4K must always be 4K or lower in resolution. This means an entirely new workflow has to be built.
As broadcasters build these new 4K workflows, they must pay attention to every production and transmission aspect involved. From capture and ingest through edit, transcode to delivery, signal integrity must be maintained.
The migration from SD to HD was less disruptive than the move from HD to 4K will be because SD images can be easily up-scaled to HD just prior to transmission.
Perhaps the first element in building a new 4K workflow involves storage. Of particular concern is the impact these much larger files will have on storage capacity and bandwidth. Analyst Coughlin Associates predicts that there will be a 5.8X increase in digital storage capacity used in the entertainment industry over the next few years and nearly a 4X increase in storage capacity shipped per year—an increase from 26,756PB to 102,661PB. This massive storage consumption includes storage associated with media workflows as well as long-term archive.
Although storage costs continue to fall, the larger file size offsets the aforementioned cost benefit. Engineers need to take a pragmatic approach to managing their facility’s data storage infrastructure. With 4K RAW footage requiring 1366MB/s per stream, building a system-wide collaborative production environment is difficult. The content must be compressed to allow existing networks, media workflow solutions, and creative talent to perform efficiently. Shared storage is a must for collaborative workflows, but must be architected in such a way as to provide the bandwidth needed in actual 4K production workflows.
4K islands and storage
Few facility operators and managers will enjoy the opportunity to build from the ground up. Instead, they will have to maintain existing operations while adding 4K capability. That is why many if not most will start by creating a separate 4K-capable workflow environment—an island. This equipment will provide the high-speed performance, future scalability, and application interoperability needed to manage 4K production. Only the island’s I/O need interface with traditional workflows. Such an approach protects existing operations and investments.
Because of the impact that 4K workflows have on storage infrastructure and because of the dependency a successful 4K workflow has on storage performance, implementing the right shared storage solution is critical. A best choice solution will meet the needs of both current and future workflows. Making a mistake on the storage and bandwidth side of the chosen solution will impact both performance and reliability. It is therefore important to keep a keen focus on system performance.
Storage has come a long way since IBM's first hard drive, which stored only 5MB. The 1956 drive consisted of a stack of fifty 24-inch discs and could be leased for $35,000 per year. That represents more than $308,000 in today's dollars. By 1985 a 40MB hard drive could be purchased for $40,000.
- Predictable Performance: As discussed earlier, 4K resolution is almost 4X greater than today’s HD formats. Additionally, 4K footage is captured at 60fps today, with 100fps anticipated in the future versus the 25fps or 30fps common with HD. The increase in both resolution and frame count provide the enhanced detail associated with 4K, while also reducing motion blur. But, the result is a 400% increase in bandwidth and storage capacity requirements compared with HD. Storage solutions must be able to provide the bandwidth needed for access to this content in real time along with low latency to guarantee zero frame loss. Even with compression, these storage networks have a bandwidth of 200Mbps.
- Interoperability: Collaborative workflows integrate a variety of applications that manage and manipulate content. Due to the improved quality of 4K content, there is more metadata, more editing inputs and outputs, and larger files. These and related factors place increased demands on the storage system being well-integrated with the facility’s other editing, media asset management, encoding and transcoding applications.
- Flexible Storage: An effective storage infrastructure balances concerns for data access and durability with requirements for performance and cost. Not all content can be kept in fast online storage forever, as it would be cost-prohibitive. An intelligent and flexible storage architecture provides fast online storage for immediate production work combined with a mechanism to seamlessly extend that online environment almost infinitely at a much lower cost. Layered across the storage infrastructure should be a centralized view of assets to streamline productivity and media access regardless of where assets are physically stored.
- Storage Network Infrastructure: 4K collaborative workflows require fast and predictable access to content. Collaboration also requires connectivity to different types of clients over different network topologies and protocols. The storage network must provide the necessary bandwidth and be flexible enough to also support required network and storage protocols.
Do your homework
The infrastructure to support 4K workflows and 4K content delivery is still evolving. And, if you are going to IBC, expect to see plenty of 4K workflow solutions on display. Keep in mind that some of these solutions are early versions and expect improvements to be made.
You do not need to upgrade or replace an entire production or broadcast environment with a 4K equivalent. Plan to upgrade in stages, beginning with a 4K-ready workflow environment that does not disrupt existing operations. This allows one to leverage technology and time. Wait and whatever you need will cost less and do more.
When building a 4K workflow, perhaps the most important element is a storage infrastructure. Look for a solution that addresses baseline 4K storage requirements as well as interoperability requirements with4K-ready creative applications. Look for a storage solution provider that offers a clear roadmap for easy, cost-effective and flexible scalability.
4K is here to stay, with 8K and 16K on the horizon. Now might be a good time to take some “baby-steps” toward that 4K environment, even if it is just an island.
Portions of this article were developed from this Quantum white paper, “4K: What you need to know and why it matters.” It is available at this link.
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