This morning at the Xilinx Developer Forum (XDF) in San Jose, Calif., Victor Peng, our CEO, was joined on stage by Dr. Yueshi Shen, principal research engineer at Twitch. During the five-minute exchange, Twitch revealed that it has selected Xilinx FPGAs to enable the industry’s first broadcast-quality, live streaming platform using the new video-encoding format, VP9.
Twitch is the largest and fastest growing live streaming video platform in North America and the first to offer a free and interactive network for watching gaming and eSports content. Dr. Shen and his team were tasked with ensuring a great live streaming experience for the millions of viewers and publishers in the Twitch community. He said it is critical to deliver broadcast-quality video, with no buffering and super-low latency.
To meet the needs of Twitch’s demanding viewer base, Dr. Shen’s team implemented a Xilinx-powered solution using the new VP9 encoding standard developed with encoder IP from Xilinx application partner NGCodec. VP9 is an open source video coding format developed by Google. It was initially used to power YouTube, but it is gaining momentum due to it being royalty-free and offering users the ability to reduce streaming bit-rates while maintaining high visual quality. NGCodec’s VP9 encoder implementation offers users further value by speeding up the encoding process while maintaining the compression efficiency of other slower implementations such as LibVPX.
Dr. Shen said his team looked at many options including CPUs, which couldn’t handle the 60 frames per-second encoding requirement, in fact, server class CPUs could only handle 4 frames per-second. His team discovered there were not any GPU or ASIC solutions that would fit the bill either. However, the server implementation of AWS F1 FPGA instances, based on Xilinx UltraScale+ FPGAs, gave them the ability to implement a solution delivering an impressive 120 frames per-second on a single FPGA, representing a 30X greater performance over a CPU implementation.
Dr. Shen explained that his team was asked to do something innovative - something that hadn’t yet been done in the industry. He said that Twitch established a design goal to deliver a 25 percent or more reduction in bitrate while keeping the video at broadcast quality – which they did! All of this needed to be done real-time to support live broadcasting.
For Twitch, the experience needs to be immersive and interactive. The company viewership is growing very fast. Fortunately, Xilinx technology enables companies like Twitch to innovate faster, which is key to staying ahead of their growing workload.
Twitch has built out its data center to support more than the peak demand, reaching beyond three million simultaneous users requiring a whopping 18 terabytes per-second — a massive bandwidth number – roughly the same as the bandwidth required to stream last summer’s World Cup!
Dr. Shen said that he and his company are very pleased with the results and wanted to share them with the tech community. "We strongly recommend the entire streaming industry to seriously consider VP9, FPGAs, and the AWS F1." Check out Twitch today, and appreciate the complexity of how this was all made possible.