Earth day 2021 is here and includes three days of events focused on global climate action. For most participants, Earth day is more than three days to act compulsory about the environment, it’s a chance to get educated and focused on the issues that society and businesses are grappling with when pushing for meaningful environmental change.
Many companies have taken oaths to become carbon neutral in the technology industry, and most are actively pushing their sustainability initiatives forward. With the great strides made, a significant pollutant still exists, and that is the proliferation of video streaming services. Cisco reports upwards of 80% of the network is consumed by video during the peak time of the day. Most companies reporting carbon emissions do so for their owned and controlled datacenters but do not account for the rest of the network, and that is where the problem lies.
Due to improvements in the energy efficiency of data centers, networks, and devices, streaming video has presented a net positive for the environment compared with traditional (physical) forms of media distribution. However, slowing efficiency gains, massive growth in users, and new demands from emerging technologies like artificial intelligence (AI) that require significant computing power raise new concerns about the overall environmental impacts of the sector — so what can we do?
The answers involve several structural changes to how we architect our networks and the technologies and standards used to encode streaming content, whether for VOD or Live delivery. Energy consumption can be managed more effectively by placing application and video encoding servers in regional data centers located close to the user. With this approach, latency is significantly reduced, and the video quality increased by employing specialized chips – Application-Specific Integrated Circuits (ASICs) – for video encoding. ASIC-based video encoders can reduce the hardware required for video processing and transcoding by a factor of ten while increasing the performance per watt by twenty times.
Energy Efficient Low Latency Video
ASIC video transcoders provide the lowest latency encoding available as compared with CPU and even GPU and FPGA approaches. With just 8ms for 1080p using HEVC, AR/VR, desktop as a service, cloud gaming, mobile gaming, and other applications requiring real-time performance are enabled. The challenge in video encoding is to balance variables that generally work against one another, such as visual quality and bitrate, or latency and visual quality. With high-energy efficient ASICs, these are no longer opposing forces.
The Trouble With CPU-Based Software Encoding
Moving video encoding to the edge requires a massive improvement in computational efficiency and performance (density) since base station deployments are expensive and physical space is minimal. For services to meet subscriber demand sustainably, a radical reduction in cost and carbon emissions footprint is needed. TIRIAS Research published in a 2020 study that transcoding 1,000 live HD video streams using CPU-based software requires 125 1RU servers and carries an operating cost of more than $580,535 each year. A software encoding workflow running in the typical cloud data center will throw off 217 Metric Tons of CO2 compared to 11.7 Metric Tons for ASIC-based encoding operations.
With NETINT ASIC-based video transcoders, 12.5 1RU servers can encode 1,000 live HD channels compared to 25 Nvidia T4 GPU instances. ASIC-powered high-density video encoding servers can easily co-locate with application processors in regional POPs or cell tower base stations. The advantage in power consumption between ASICs and GPU or CPU-based encoding is proportional to the environmental impact and reduced carbon emissions. See Figure 1.
Environmental Considerations of Video Encoding
Datacenter and large-scale service operators face a renewed challenge of decreasing energy consumption to lower operating costs and emissions while maintaining the quality of service their subscribers expect. Environmental impact is hard to manage as users embrace new services, computational workloads, and usage increase, placing pressure on data centers to increase capacity which drives up power and carbon emissions.
Rarely does an opportunity arrive to create an order of magnitude reduction in carbon emissions. Figure 2 shows the power consumption and CO2 impact of video encoding by comparing CPU and ASIC-based video encoding operation data, kWh, and CO2 emissions per year.
Using 1,000 concurrent live 1080p30 channels for a baseline, ASIC-based encoding efficiency results in 27,375 kWh per year, leading to 11.6 Metric Tons of CO2 emissions. Comparatively, CPU-based encoding consumes 509,175 kWh per year, throwing off 217 Metric Tons of CO2. TIRIAS Research estimates that by 2025, with over 40 million concurrent streams, cloud encoding using x86 CPUs will produce 8,680,000 Metric Tons/Year of CO2 emissions, equivalent to the exhaust output of 1,000,000 conventional automobiles. By comparison, video encoding based on ASICs would reduce the number of cars to 53,917. Video encoding ASICs deliver a 20X improvement in energy efficiency over CPUs!
Streaming Sustainability – The Future
According to The Shift Project — watching Internet-delivered (streamed) video accounts for the most significant chunk of network traffic. Online video generates 300 Million Metric Tons of CO2 each year, roughly 1% of global emissions. Approximately one-third of the video traffic is adult content. Premium on-demand video services like Netflix and Amazon Prime account for a third. The final third includes watching YouTube and social media videos.
About games — Researchers behind a study at the University of California found US gamers use 2.4% of their household’s electricity or 32 terawatt-hours of energy every year. Particularly worrisome is that streaming games consume more energy than console-based gameplay, meaning that carbon emissions may worsen as more people migrate to cloud gaming platforms.
The environmental future that we want will require changes in how we encode and distribute video if we hope to simultaneously meet our user’s expectations while making progress towards sustainability. ASIC-powered encoders offer a breakthrough in density, performance, and cost, enabling edge-located video applications to scale economically while significantly reducing environmental impact. By lowering latency, ASIC transcoders can enable real-time video solutions and interactive entertainment experiences like cloud gaming and AR/VR to be delivered sustainably and profitably.