Video Systems in an IT Environment

The Basics of Professional Networked Media and File-based Workflows

Al Kovalick

• Publisher: Routledge
• Year: 2013
• ISBN:
  9781136035937
• Edition: 2
• Topic: Languages & Linguistics
• Subtopic: Communication Studies
• Index: Languages & Linguistics

Audio/Video (AV) systems and Information Technology (IT) have collided. IT is being leveraged to create compelling networked media and file-based workflows. Video Systems in an IT Environment has helped thousands of professionals in broadcast, post and other media disciplines to understand the key aspects the AV/IT "tapeless convergence. World-renowned educator and speaker Al Kovalick adds his conversational and witty style to this text making the book an enjoyable learning experience. Now in its second edition, this book includes: basics of networked media, storage systems for AV, MXF and other file formats, Web services and SOA, software platforms, 14 methods for high availability design, element management, security, AV technology, transition issues, real-world case studies and much more. Each chapter weaves together IT and AV techniques providing the reader with actionable information on the issues, best practices, processes and principles of seamless AV/IT systems integration.

CHAPTER 1

Networked Media in an IT Environment

CONTENTS

1.0 Introduction

1.1 What is Networked Media?

1.2 Motivation Toward Networked Media

1.2.1 Force #1: Network Infrastructure and Bandwidth

1.2.2 Force #2: CPU Compute Power

1.2.3 Force #3: Storage Density, Bandwidth, and Power

1.2.4 Force #4: IT Systems Manageability

1.2.5 Force #5: Software Architectures

1.2.6 Force #6: Interoperability

1.2.7 Force #7: User Application Functionality

1.2.8 Force #8: Reliability and Scalability

1.2.9 The Eight Forces: A Conclusion

1.3 Three Fundamental Methods of Moving A/V Data

1.4 Systemwide Timing Migration

1.5 Can “IT” Meet the Needs of A/V Workfl ows?

1.6 Advantages and Disadvantages of Methods

1.6.1 Trade-off Discussion

1.7 It’s A Wrap: Some Final Words

References

1.0 INTRODUCTION

Among his many great accomplishments, Sir Isaac Newton discovered three fundamental laws of physics. Law number one is often called the law of inertia and is stated as Every object in a state of uniform motion remains in that state unless an external force is applied to it.

By analogy, this law may be applied to the recent state of A/V system technology. The traditional methods (state of uniform motion) of moving video [serial digital interface (SDI), composite …] and storing video (tape, VTRs) assets are accepted and comfortable to the engineering and production staff, fit existing workflows, and are proven to work. Some facility managers feel, “If it’s not broken don’t fix it.” Ah, but the second part of the law states “… unless an external force is applied to it.” So, what force is moving A/V systems today into a new direction—the direction of networked media? Well, it is the force of information technology (IT)¹ and all that is associated with it. Is this a benign force? Will its muscle be beneficial for the broadcast and professional A/V production businesses? What are the advantages and trade-offs of this new direction? These issues and many more are investigated in the course of this book. First, what is networked media?

1.1 WHAT IS NETWORKED MEDIA?

The term network in the context of our discussions is limited to a system of digital interconnections that communicate, move, or transfer information. This primarily includes traditional IT-based LAN (Ethernet in all forms), WAN (Telco-provided links), and Fibre Channel network technologies. Some secondary linkages such as IEEE-1394, USB, and SCSI are used for very short haul connectivity. The secondary links have limited geographical reach and are not as fully routable and extensible as the primary links.

In contrast to traditional A/V equipment,² networked media relies on technology and components supplied by IT equipment vendors to move, store, and manipulate A/V assets. With all respect to the stalwart SDI router, it is woefully lacking in terms of true networkability. Only by Herculean feats can SDI links be networked in similar ways to what Ethernet and Internet Protocol (IP) routing can offer.

The following fundamental methods and concepts are examples of networked media.

• Direct-to-storage media ingest, edit, playout, process, and so on

• 100 percent reliable file transfer methods

• A/V streaming over IT networks

• Media/data routing and distribution using Ethernet LAN connectivity, Fibre Channel, WAN, and other links with appropriate switching

• Networkable A/V components (media clients): ingest ports, edit stations, data servers, caches, playout ports, proxy stations, controllers, A/V process stations, and so on

• A/V-as-data archive; not traditional videotape archive

For the most part, file-based technology and workflows (so-called tapeless) use networked media techniques. So, file-based technology is implemented using elements of AV + IT systems and is contrasted to stream-based throughout this book. Also, the AV/IT systems domain is a superset of the file-based concepts domain. Figure 1.1 illustrates the relationships between the various actors in the AV/IT systems domain.

FIGURE 1.1 Professional video system components.

The world of networked media spans from a simple home video network to large broadcast and postproduction facilities. There are countless applications of the concepts in the list just given, and many are described in the course of the book. We will concentrate on the subset that is the realm of the professional/enterprise (and prosumer) media producer/creator. Figure 1.2 illustrates the domain of the general professional video system, whether digital or not.

FIGURE 1.2 Switching, routing, connectivity.

The components are connected via the routing domain to create an unlimited variety of systems to perform almost any desired workflow. Examples of these systems include the following:

1. Analog based (analog tape + A/V processing + analog connectivity)

2. Digitally based (digital tape + A/V processing + digital connectivity)

3. Networked based (data servers + A/V processing + networked connectivity)

4. Hybrid combinations of all the above

The distinction between digitally based and networked based may seem inconsequential, as networks are digital in nature. Think of it this way: all networks are digital, but not all digital interconnectivity is net-workable. The ubiquitous SDI link is certainly digital, but it is not easily networkable. Over the course of discussions, our focus highlights item #3 as primary, with the others taking on supporting roles. Items #1 and #2 are defined for our discussions as “traditional A/V” compared to item #3, which is referred to as “AV/IT or IT-based AV” throughout this book.

Again, looking at Figure 1.1, most of the components may be combined in various ways to make up an IT-based professional video system. However, three elements have extended applications beyond our consideration. The world of media acquisition and distribution is enormous and will not be considered in all its glory. Also, media distribution methods using terrestrial RF broadcast, cable TV networks, the Web, and satellite are beyond our scope. Additionally, live (sporting events, news, etc.) production methods (field cameras, vision mixers) fall into a gray area in terms of the application of IT. However, most new field cameras don’t use videotape; instead, they use use file-based optical disc or flash memory for storage. These offer nonlinear access and network ports.

1.2 MOTIVATION TOWARD NETWORKED MEDIA

Over the past few years, there has been a gradual increase in new A/V products that steal pages from the playbook of IT methods. Figure 1.3 shows the changing nature of video systems. At the core are untimed, asynchronous IT networks, data servers, and storage subsystems. At the edges are traditional timed (in the horizontal and vertical raster-scanning sense) A/V circuits and links that interface to the core. The core is expanding rapidly and consuming many of the functionalities that were once performed solely by A/V-specific devices. This picture likely raises many questions in your mind. How can not-designed-for-video equipment replace carefully designed video gear? How far can this trend continue before all notion of timed video has disappeared? What is fueling the expansion? Will the trend reverse itself after poor experiences have accumulated? Our discussions will answer these questions.

FIGURE 1.3 The expansion of the IT universe into A/V space

There is no single motivational force responsible for the shift to IT media. There are at least two levels of motivational factors: business related and technology related. At the business level there is what may be called the prime directive. Simply put, owners and managers of video and broadcast facilities are demanding, “I want more and better but with less.” That is a tall order, but this directive is driving many purchasing decisions every day. More what? More compelling content, more distribution channels, more throughput. Better what? Better quality (HD, for example), more compelling imagery, better production value, better branding. Less what? Less capital spending, less ongoing operational cost, fewer maintenance headaches. All these combine to create value and the real business driver—more profit. Of course, there are many aspects to more/better/less, but let us focus our attention on the technical side of the operations. If we want to achieve more/better/less, the technology selection is key. The following sections examine this aspect.

Of course, there are issues with the transition to the AV/IT environment from the comfortable world of traditional A/V video. All is not peaches and cream. The so-called move to IT has lots of baggage. The following sections focus on the positive workflow-related benefits of the move to IT. However, in Chapter 10, several case studies examine real-world examples of those who took the bold step to create hybrid IT and A/V environments. In that chapter you will feel the pains and joys of the implementers on the bleeding edge. In that consideration we examine the cultural, organizational, operational, and technical implications of the move to IT.

At least eight technical forces are combining to create a resulting vector that is moving media systems in the direction of IT. Let us call the area enclosed by the boundary contour of Figure 1.4 the system IQ. This metric is synthetic, but consider the area (bigger is better) as a measure of a system’s “goodness” to meet or exceed a user’s requirements. Each of the eight axes is labeled with one of the forces. Let us devote some time to each force and add insight into their individual significance. Also, for each force, a measure of workflow improvement due to the force is described. After all, without an improvement in cost savings, quality, production value, resource utilization, or process delay, a force would be rather feeble. Although the forces are numbered, this is not meant to imply a priority to their importance.

FIGURE 1.4 Eight forces enabling the new AV/IT infrastructure.

1.2.1 Force #1: Network Infrastructure and Bandwidth

The glue of any IT system is its routing and connectivity network. The faster and wider the interconnectivity, the more access any node has to another node. But of what benefit is this to a media producer? What are the workflow improvements? Networks break the barrier of geography and allow for distributed workflows that are impossible using legacy A/V equipment. For example, imagine a joint production project with collaborating editors in Tokyo, New York City, and London (or among different editors in a campus environment). Over a WAN they can sha...

Table of contents

• Cover
• Halftitle
• Title
• Copyright
• Dedication
• Contents
• Acknowledgments
• Introduction
• 1. Networked Media in an IT Environment
• 2. The Basics of Professional Networked Media
• 3A. Storage System Basics
• 3B. Storage Access Methods
• 4. Software Technology for A/V Systems
• 5. Reliability and Scalability Methods
• 6. Networking Basics for A/V
• 7. Media Systems Integration
• 8. Security for Networked A/V Systems
• 9. Systems Management and Monitoring
• 10. The Transition to IT: Issues and Case Studies
• 11. A Review of A/V Basics
• Appendix A. Fast Shortcuts for Computing 2N
• Appendix B. Achieving Frame Accuracy in a Non-Frame Accurate World
• Appendix C. Grid, Cluster, Utility, and Symmetric Multiprocessing Computing
• Appendix D. The Information Flood—One Zettabyte of Data
• Appendix E. 8B/10B Line Coding
• Appendix F. Digital Hierarchies
• Appendix G. 270 Million—A Magic Number in Digital Video
• Appendix H. A Novel A/V Storage System
• Appendix I. Is It Rabbits Multiplying or Is It Streaming?
• Appendix J. How to Evaluate a Video Server
• Appendix K. Blade Servers
• Appendix L. Solid State Discs Set Off Flash Flood
• Appendix M. Will Ethernet Switches Ever Replace Traditional Video Routers?
• A Glossary of AV/IT Terms
• Index