Shape Mode

Purpose

• Modify an input plex into any number of different helpful output formats.

Usage

metrical shape <COMMAND> [COMMAND_OPTIONS] <PLEX_OR_RESULTS_PATH> <OUTPUT_DIR>

Concepts

For a single-camera system, a plex is a simple affair. For a complicated multi-component system, plexes can become incredibly complex and difficult to parse. Unlike other calibration systems, MetriCal creates fully connected graphs whenever it can. Everything is related!

This is where Shape mode comes in handy. Shape modifies a plex into a variety of different and useful configurations. It was created with an eye towards the practical use of calibration data in a deployed system.

Some Shape commands, like mst and focus, rely on the covariance of each spatial constraint in the plex to inform the operation. Since the covariance is a measure of uncertainty, we can use it to carve out the "most certain" constraints between two components.

Other Shape commands will mutate the plex into something useful for another application, such as the urdf command for ROS applications.

Commands	Purpose
focus	Create a plex in which all components are spatially connected to only one "focus" component, i.e. a "hub-and-spoke" plex.
lut	Create a pixel-wise lookup table for a single camera.
stereo-lut	Create two pixel-wise lookup tables that produce a rectified stereo pair.
mst	Create a plex from the Minimum Spanning Tree of all spatial constraints.
tabular	Re-encodes the calibration data in a plex as a series of compressed tables.
urdf	Create a ROS-compatible URDF from this plex.