The analog-to-digital surveillance system evolution is being driven by technology innovations and the promise of significant market growth and the higher revenues that accompany it. Today's H.264 video compression capabilities, fast networking connectivity and megapixel cameras provide a strong basis for transition to digital-based systems. As these innovations are advancing surveillance capabilities, they are also creating the need for more capacious storage. An eight megapixel camera can produce one terabyte of data in just three days. Even with strides in video compression, the surveillance community is constantly looking at how to cost-effectively integrate these increasingly data-intensive cameras with standalone video recorders. High capacity AV-class hard drive storage has quickly become an industry-enabling design element necessary to sustain a workable digital solution.
Industry analysts have predicted that transitioning security surveillance systems to digital from analog is the most important challenge facing the security video market. The digital video revolution has opened the door for camera resolutions to increase at an even faster pace. This is why it is essential that security system integrators have a clear understanding of the optimal storage capacity and possible system compatibility issues for a given video surveillance application. Integrators need a method for calculating storage needs based on video resolution and standards, recording hour requirements and the number of cameras used in the system.
Hard drive innovation
Hard drive storage is the platform that facilitates the move from outdated and cumbersome tape-based systems to digital systems. Due to constant innovation, hard drive manufacturers have consistently delivered increased storage capacity while keeping prices affordable. Audio/video (AV) surveillance and security applications can take advantage of these huge technology achievements that have made hundreds of terabytes or even petabytes of storage available. AV-Class hard drives have been engineered to not only provide the performance necessary to access and retrieve stored video quickly, they can also deliver the high capacity points that enable higher resolution video streams to be stored more efficiently and cost-effectively. Western Digital is committed to serving the security market and was the first to introduce a two-terabyte drive designed for surveillance. This landmark capacity point enables surveillance systems with two or more cameras to record high levels of clarity (30 frames per second) at a broad range of resolution settings and still store 30 days or more of video footage.
Using high-capacity surveillance drives will become even more important as high definition (HD) becomes increasingly pervasive. Capacity is by no means the only enabling hard drive innovation for the surveillance market. Other elements include lower thermals (and therefore higher reliability and longer product life), low power consumption, inaudible 24x7 operation, universal system compatibility and the ability to simultaneously record multiple audio and/or high-definition video streams.
High reliability and product longevity
Storage reliability is paramount to maintaining long product life of surveillance systems. Today's hard drives for surveillance systems have been specifically designed and tested for long product deployments in always-on streaming digital audio/video environments. Drives that have been specifically designed for these intensive applications typically feature a high Mean Time Before Failure (MTBF) of 1 million hours, which is higher than desktop or notebook PC hard drives. Advanced hard drive technologies that help ensure system longevity and endurance are also available such as Preemptive Wear Leveling (PWL), which has been integrated into several hard drives from Western Digital.