POLYCHASE BLENDER ADDON FREE ALTERNATIVE FOR KeenTools GeoTracker.

Polychase
A free and open-source motion tracking addon for Blender, inspired by KeenTools GeoTracker.

Overview
Polychase is a 3D motion tracking solution that allows you to track camera movement or object motion in video footage within Blender. It uses optical flow analysis and PnP, aided by user input to provide accurate tracking results.

Features
Core Tracking Capabilities
3D Pin Mode: Place and manage tracking pins on 3D geometry
Camera/Geometry Tracking: Track camera/geometry movement through 3D space
Trajectory Refinement: Refine tracking results using bundle adjustment
Advanced Features
Variable Camera Parameters: Support for estimating focal length and principal point
Keyframe Management: Complete keyframe control for tracked animation
Scene Transformation: Transform entire tracked scenes
Animation Conversion: Convert between camera and object tracking
Real-time Preview: Live tracking progress and results
Mask Support: 3D masking for selective tracking
User Interface
Integrated Blender UI: Native Blender panels and operators
Visual Feedback: Color-coded pins, wireframes, and progress indicators
Customizable Appearance: Adjustable pin colors, sizes, and wireframe styles
Usage
Basic Workflow
Setup Scene:

Import your video footage as a movie clip
Add or import the 3D geometry you want to track
Set up a camera object
Create Tracker:

Open the Polychase panel in Blender’s 3D viewport
Create a new tracker
Assign your clip, geometry, and camera
Analyze Video:

Set the database path for optical flow storage
Run “Analyze Video” to generate optical flow data
Pin Mode:

Enter pin mode to place tracking points on your 3D geometry
Add pins by clicking on the geometry surface
Drag the pins to adjust the pose of the geometry/camera
Track Sequence:

Choose tracking direction (forward/backward)
Select tracking target (camera or geometry)
Run tracking to generate keyframes
Refine Results:

Use the refine sequence tool to improve tracking accuracy
Pin Mode Controls
Left Click: Add new pin
Right Click: Delete pin
M: Go to mask drawing mode
ESC: Exit pin mode
Technical Details
Architecture
C++ Core: High-performance tracking algorithms written in C++
Python Bindings: pybind11 integration for Blender compatibility
Blender Integration: Native Blender addon with custom operators and panels
Algorithms
Optical Flow: Off-the-shelf OpenCV solution
3D Tracking: PnP (Perspective-n-Point) solving for camera pose estimation
Bundle Adjustment: Global non-linear optimization for trajectory refinement
Ray Casting: Accelerated mesh intersection using Embree