Master the Modes: Explaining HyperSmooth
GoPro loves pushing boundaries—the gnarlier the line, the crazier the footage, the better the shot. But we’ve found there is a direct correlation between send-factor and shake-factor—i.e. the more you send it, the shakier the footage. With HERO7 Black, we tasked the team with eliminating shaky footage, and this is when HyperSmooth was born. The following is a look into HyperSmooth written by with senior engineer of algorithms Maxim Karpushin.
There are two ways to stabilize video—physically and electronically. When conceptualizing HERO7 Black, instead of teaching users to stabilize physically, we wanted to find a way to smoothen footage internally, or electronically. This put the wheels in motion for the creation of HyperSmooth, a novel stabilization technique that analyzes raw camera motion and transforms it into stabilized motion.
HyperSmooth is all about the motion. It proactively analyzes movement in real time, so the available stabilization margin is used in the best possible way—eliminating the shake you don’t want, while maintaining the subject you do want. This combined with our proprietary rolling shutter correction algorithm, allows HERO7 Black to deliver gimbal-like stabilization without the dreaded jello effect. In order for HyperSmooth to work, we also ramped up the power of the GP1 Chip (which was introduced in the HERO6 Black) and added an additional 1GB of SDRAM.
A word on Electronic Image Stabilization
HyperSmooth is fully electronic. Electronic image stabilization (EIS) works by cropping in a small amount from the edge of a frame to lessen camera motion. This cropped part is known as the “stabilization margin;” GoPro has a stabilization margin of about 5%.
Compared to other stabilization techniques EIS has three major strong points.
- There are no moving parts. Meaning your GoPro is as durable, waterproof and robust as it always was. This is a great advantage because optic image stabilizers (OIS) may be easily damageable.
- High frequencies are compensated for (almost) instantaneously. Mechanical gimbals may have hard time dealing with high-frequencies due to inherent mechanical limits. The motors aren’t capable of reacting fast enough to compensate, while the EIS works at the speed of light (well, nearly, actually).
- EIS works everywhere. Underwater or outer space? Still works! Again, mechanical gimbals may have hard time dealing with a surrounding viscous medium (i.e. water) or in the absence of gravity. The latter is true both in space and in a free fall scenario.
HyperSmooth Tips and Tricks
Here are some best-practices to help you get the most out of HyperSmooth.
- Zoom in for extremely shaky activities. You may sacrifice some field of view (FOV), but the return is an increased stabilization margin. HyperSmooth uses the zoom as additional stabilization margin. Often a very little zoom (10-15%) is enough to substantially increase the motion attenuation capacity. Plus, the FOV loss is barely visible.
- There is even more margin in Linear Mode. Similar to the reasoning above, Linear Mode essentially acts as heightened HyperSmooth thanks to an inherintly larger stabilization margin when compared to the Wide FOV. Plus, the straight lines remain straight.