Inertial Stabilization Options

[Andrew Hazelden]

Adrian Eddy, the GyroFlow developer just added "motion data" export options in the latest GyroFlow development build. 🎉

You can now use the GyroFlow program and directly save out the final processed IMU (inertial sensor) data exports into formats like CSV (Comma Separated Value), JSON, OpenUSD (.usd), and After Effects JSX.

Start by importing your video into GyroFlow and adjust the settings until you are happy. Then click on the lower left part of the GyroFlow window on the "Export -> Export Camera Data" text. When exporting JSON and CSV data from GyroFlow, life is a lot easier if you enable the "One Sample Per Frame" option. You also want "Euler angles" in the output, too.

This new GyroFlow export feature makes it feasible to do post-processed stabilization on 180VR and 360VR video in a far wider range of DCC tools. The IMU motion data comes from metadata embedded in the "camera original" recorded video files.

For VFX artists who can handle advanced workflows, it is technically feasible to use a synced "witness camera" that is aligned and rigidly mounted on a 360VR camera array. Using a 4x4 transform matrix, with a "matrix multiply" operation, one can apply that witness camera footage's per-frame IMU rotation data info onto another camera's stitched or unstitched video clip. What you need to do though, is work out the rotational offset on the yaw/pitch/roll axis of the source and target camera views.

To make life easier, the Kartaverse "Vonk Ultra" data node toolset had a mini update today to improve the way GyroFlow CSV and JSON exported IMU records are used inside the Resolve/Fusion page. Rendering performance was boosted 3X when working with XYZ channel data in parallel.

Note 1: Having native export support in the main GyroFlow app, now replaces the prior efforts of the GyroFlow-To-CSV python script usage. This sure makes life a lot simpler! Yay!

Note 2: If you want to work with JSON data in Fusion, your best bet is to master the Vonk Ultra nodes that work with a data type called a "ScriptVal". This approach lets you pass a container like structure down the node graph that can store a wide range of data records in custom hierarchies.

The Inspector panel's "Connect To" contextual menu allows you to bind individual animation channels to another node's output.

Regards,
Andrew Hazelden
Kartaverse Developer