Whitepaper: A Real-time VVC Software Encoder for UHD Live Video Applications v2.0

By Sergio Sanz-Rodríguez, PhD and Mauricio Alvarez-Mesa, PhD – Spin Digital has recently announced the support for real-time VVC/H.266 encoding in its 8K live encoder (Spin Enc Live) application and Media SDK (Spin SDK). Along with these product releases, Spin Digital has updated the whitepaper that describes in detail the compression and performance of the new real-time VVC encoder.

The whitepaper can be downloaded from this link.

What’s New

The first version of the VVC live encoding whitepaper was published in August 2022 when we announced the VVC live encoder for the first time. Compared to the first edition, this Whitepaper v2.0 includes the following updates:

• Analysis of Spin Digital VVC Encoder for 4K and 8K live encoding
• Comparison with recent versions of the open-source software encoders: x264 (H.264), x265 (HEVC), SVT-HEVC (HEVC), SVT-AV1 (AV1), VVenC (VVC)
• Comparison with GPU-based hardware encoders: Nvidia NVENC (HEVC), Intel OneVPL (AV1)
• Comprehensive comparison of encoders for 4K and 8K streaming and broadcasting use cases

Highlights

The main highlights of the VVC real-time encoder developed by Spin Digital are:

• Higher compression efficiency than a state-of-the-art HEVC live encoder
• Higher compression efficiency than hardware-accelerated encoders
• Higher performance than optimized software and hardware-accelerated encoders
• Real-time UHD video encoding on a single dual-socket server
• Ready for 4K/8K live streaming and broadcasting

Higher Compression Efficiency Than a State-of-the-art HEVC Real-time Encoder

The VVC encoder (Spin Digital VVC) achieves, for 4K video, a BD-rate reduction of 17.5% with respect to a highly optimized HEVC real-time encoder (Spin Digital HEVC). This has been possible with a 65% increase in  computational complexity compared to  Spin Digital HEVC, which has been proven feasible with current generation of CPU architectures.

The results for 8K video have shown that Spin Digital VVC achieves a BD-rate savings of 27.2% relative to the HEVC live encoder with 1.47 times higher complexity.

As shown in Figure 1, Spin Digital VVC encoder achieves the highest compression efficiency when compared to other encoders including H.264 (x264), HEVC (x265, SVT-HEVC) and AV1 (SVT-AV1) for the complexity range required for real-time UHD applications (around 1.0x to 2.0x the complexity of the base HEVC encoder).

Higher Compression Efficiency Than Hardware-accelerated Encoders

Spin Digital VVC encoder is able to significantly reduce the bitrate at the same quality (higher compression efficiency) than the GPU-based hardware accelerated encoders, when targeting 4K 60 fps real-time performance.

The NVENC-HEVC and OneVPL-AV1 encoders at their highest quality presets that produce a performance above 60 fps result in a BD-rate increase of about 20% relative to Spin Digital HEVC. When compared to Spin Digital VVC, these  encoders produce BD-rate increases of 40% to 45%, respectively (see Figure 1).

Higher Performance Than Optimized Software and Hardware-accelerated Encoders

When running on a multi-core CPU system targeting 4K 60 fps real-time operation, the Spin Digital VVC produces the required encoding performance and results in the highest compression efficiency (lowest bitrate for the same quality) when compared to optimized open-source HEVC and AV1 software encoders such as x265, SVT-HEVC, and SVT-AV1, as well as GPU-based hardware encoders such as NVENC-HEVC and OneVPL-AV1 (see Figure 2).

Real-time UHD Video Encoding on a Single Dual-socket Server

Spin Digital’s VVC encoder is a highly-optimized CPU-based software solution that can process 4K video at 60 fps as well as 8K video at 30 fps, both in 10-bit HDR, in real-time on a single server with two Intel Xeon Platinum CPUs with a total of 76 CPU cores (see Figures 2 and 3).

Ready for 4K/8K Live Streaming and Broadcasting

The VVC encoder has been integrated into a complete application for  live encoding and streaming (called Spin Enc Live), as well as a module in Spin Digital Media SDK (Spin SDK) and a plugin for FFmpeg.

Spin Enc Live and Spin SDK include all the components and their integrations for 4K and 8K live streaming including: input capture via SDI and IP, pre-processing, pre-analysis, advanced rate control, audio and video encoding, and broadcast over IP and HTTP streaming.

Together with Spin Digital’s VVC decoder and media player (Spin Player VVC), the end-to-end VVC encoding, streaming, and playback workflow has been successfully validated for 4Kp60 and 8Kp30 videos and presented at IBC 2022 and InterBEE 2022.

Real-time 8Kp60 VVC Encoding on Spin Digital’s Horizon

The VVC encoder assessed in this whitepaper is the first generation of a VVC CPU-based software implementation, and it is expected that the encoder will improve over time for delivering UHD live video at higher quality with lower bitrates. VVC live encoding improvements will emerge with the use of new and more advanced encoding algorithms combined with the increased performance of next-generation CPU architectures. As a result, it is expected that the VVC encoder will be able to compress 8Kp60 10-bit HDR video in real-time for live applications with increased compression and quality.