Microsoft: We’ve halved the power used by Teams video meetings to save your PC

Microsoft has been working on improvements to its hit video meeting app Teams to create “equitable experiences” across cheap and high-end Windows PCs.

Video calls are a key feature of Teams and this is one area Microsoft has targeted to reduce power consumption by cutting the CPU and graphics loads when using a video camera with the app. 

Since June 2020, Teams CPU and memory usage has been halved, according to Microsoft's internal measurements.      

“We're committed to ensuring great calling and meeting experiences for users on low-end hardware as well as those on high-end workstations and high-resolution monitors,” explains Robert Aichner, a program manager at Microsoft Research who focusses on using machine learning to improve audio and video quality.  

“One of the factors we've addressed is the difference in power requirements for different customer profiles by ensuring Teams meetings are as energy-efficient as possible, regardless of setup.”

Microsoft engineers have worked to improve camera-related optimizations to reduce the load on the CPU and improve GPU usage in video meetings, in particular where meetings have over 10 users. It's also worked on simplifying code for automatic features like exposure, white balance, and aliasing. 

Aichner says Microsoft has been testing power consumption for video calls and screen sharing, which generates energy-hungry processes during content capture, encoding, and rendering. 

“Isolating and optimizing each of these processes enabled us to reduce power consumption up to 50% for energy-intensive scenarios such as having over 10 users in a meeting when everyone has their video turned on,” explains Robert Aichner, a program manager at Microsoft Research who focuses on using machine learning to improve audio and video quality.  

Microsoft found out major improvements by redesigning how Teams handles grid videos with multiple participants.

“A simple 3×3 video grid once required nine distinct rendering operations. By combining the streams and composing them into a single video, we have been able to consolidate operations in video rendering and significantly reduce the power requirements for each device used,” says Aichner. 

It also enabled the Teams app to use the device's GPU in both meetings and video previews. Microsoft says will continue to “work closely with CPU and GPU chipset vendors to ensure the next generation of silicon is further optimized for Teams video conferencing.”

Teams is facing stiff competition from Zoom, Google Meet, Slack and Cisco's Webex and performance is one of the key battle grounds to winning and keeping more users on Teams. Microsoft in January said Teams had 270 million monthly active users and is trying to grow that number through the consumer-focussed Windows 11 Teams Chat button.