Zeeshan Ali , Lead Video Compression Engineer , Dish TV

"In the increasingly competitive market, video providers have to continually innovate and enhance the customer viewing experience by supporting new standards such as 4K UHD TV."

The media and entertainment video transcoding market was actually on a downward trajectory, but with the introduction of software into the broadcast sector – that was previously considered hardware centric – has been a boon to market growth. New open source technologies, as well as commercial software are popping up every day.

On fuelling the software-based transcoding

Software running on normal processors can now surpass task-specific video processing equipment in terms of both picture quality and performance while simultaneously adapting to the requirement of the ever-changing market.

Software-based video is a comparatively more affordable approach to implementing flexible, scalable, and easily upgradable video architectures. Unlike the legacy systems, this software-based technique allows video providers to deploy software across an optimal combination of dedicated and virtualized resources in various data centers. A software-based approach gives video providers freedom from the constraints of dedicated equipment by allowing for the best architecture and processor combination to be used for a particular application, even if the application changes over time the software can easily adapt according to the requirements of the application.

Apart from all this the video transcoding market has gotten a boost from several factors:

Growing need for transcoding with increasing number of portable devices. Increased sales of handheld devices as well the internet penetration have driven up the video consumption and the providers now can deliver optimal video experience to the consumers.

Striking growth in video streaming services. With the availability of numerous online streaming service providers like Netflix, iFlix, Amazon to name a few, the consumers now have a wide range of services to choose.

Availability of cloud-based transcoding. Onsite transcoding is a costly and lengthy process to set up. Cloud-based solution on the other hand can significantly reduce the initial investment and time. Shifting live workflows to the cloud everyday makes more sense as capacity increases costs decrease, technologies mature, and the financial trade-off between top-line revenue growth and bottom-line savings becomes much more difficult to ignore.

With the flexibility available in software, video providers can immediately respond to changes in consumer demand. Support for new features and standards can be added through simple software upgrades and API integration of third-party software.

Broadcasters and pay TV operators, if they choose software-defined video solutions do not have to wait for new custom video chips to be released to market. Instead, they can continually update and enhance their platform in line with ever-increasing consumer demand and technology advancements to create new revenue-generating video services.

In the increasingly competitive market, video providers have to continually innovate and enhance the customer viewing experience by supporting new standards such as 4K UHD TV. Software-based video systems used to process MPEG-2 video can offer a more seamless migration path to H.264 and HEVC than dedicated hardware equipment.

On migration from hardware to software-based encoding

Despite the flexibility and cost-efficiency benefits of moving compression operations to software, companies have to consider an assortment of variables. Any shift from hardware-based encoding to software-based encoding will depend upon a number of factors.

  • Equipment replacement cost, including licensing and support
  • How to reutilize the existing infrastructure and the complexity of the conversion
  • What distribution formats and resolutions to use
  • Technical factors such as video quality and latency

On hardware versus software

Hardware Compression. As we are well aware that hardware encoding has been regarded as the best option for high video quality compression platforms because hardware encoders use processors that are specifically designed for the job at hand, they only process the algorithms required.

Hardware compression uses ASICs (application specific integrated circuits) for encoding processing and FPGAs (field programmable gate arrays) to support any additional transport stream (TS) processing or video analysis. But the higher processing performance and power efficiency comes at a cost.

Hardware encoding leads to lower latency and in hardware compression, latency depends on the encoding type and profile used. Distribution encoding latencies are typically higher, but deliver better bitrate efficiency. Hardware encoders are mostly used in static, point-to-point systems that are reconfigured rarely or not at all during their operation.

Various advances in compression technologies, such as H.264 and HEVC (high-efficiency video coding), have enabled the delivery of more and higher-quality services over existing infrastructures like terrestrial, satellite, and cable. While H.264 delivers the same quality as MPEG-2 at approximately half the bandwidth required by MPEG-2, HEVC is twice as efficient as H.264.

The dedicated ASICs tend to be lower cost for the performance they provide and require less power. The two key components in the process of selection for any encoding solution are flexibility of the system and key functions (can it be re-programmed?)

Every time a new codec is introduced, new hardware is needed. An alternative solution for hardware encoding is an FPGA-based encoder, which provides the flexibility of being reprogrammable and has a faster time to market. One key drawback, however, is their lower level of density and a greater cost trade-off when compared to an ASIC-only implementation not just in terms of expense but also power consumption. Hardware-based encoding often has higher upfront costs but lower running costs, such as maintenance and power consumption, than a service-based software approach.

Software Compression. The costs for a software-based approach, however, depend on whether the encoder is local or virtualized in the cloud. Outside of a cloud model, the upfront costs can be comparable to hardware. A cloud model offers low initial costs but higher operating costs.

The main difference between hardware and software encoding is that software encoding uses standard server platforms that are widely available through major IT providers and can simultaneously process a multitude of computations.

Software-based encoders have been regarded since the beginning as not delivering the same quality as hardware encoders in real time. But those deficiencies are disappearing. Video quality deficiencies in the past were not due to the software but due to the processing power in the servers, which did not meet the need for real-time performance.

The processing power of servers has risen drastically, meaning software can do more and more in real time that was not possible in the past. We have now reached a point where software is becoming cost effective and is meeting the required level of channels and quality and performance needed.

Running compression operations on generic server platforms offers significant flexibility and versatility. Software-based encoding is also well tailored to cloud-based and OTT applications and is now widely being used. These applications require the transcoding of multiple ABR streams of the same content to accommodate changes in transmission bandwidth for differing receiving devices.

The ability to flexibly and cost-efficiently repurpose existing content to OTT and ABR platforms can increase revenue and market share for both content owners and distributors. Achieving the required balanced compression strategy depends on a number of factors, including technical and business requirements, as well as budgetary considerations.

Choosing between providing high-quality service over cable and satellite or providing hundreds of thousands of services to multiple devices requires a comprehensive and optimized compression strategy.

On hybrid system – combination of software and hardware compression

Combining both hardware and software compression solutions in a hybrid approach will provide professionals the ability to customize a compression system that most efficiently balances video quality, flexibility, and costs. A hybrid approach, will rely on ASICs-based hardware to manage the complexities of encoding and software to manage other requirements, including TS processing or video analysis, removing the need for FPGAs. A hybrid solution will give media companies the ability to provide better solution while at the same time, simplifying the process of adding new features, while maintaining video quality due to the advanced computational power of the hardware used.

The use of a software encoder to enhance a hardware encoder can extend the useful life of a hardware encoder, allow the system to adapt to changes in video coding standards, and in some cases improve performance of the encoding implemented by hardware or software alone.

The overall view is that a hybrid system will be more efficient than a stand-alone software or hardware compression system.