YUV Sensor Data Processor (yuv_sensor)

Toolkit for decoding raw YUV_420_888 camera frames, aligning IMU sensor logs, and preparing data for 3D reconstruction pipelines (e.g., COLMAP). Designed for mobile scanning workflows (object/indoor capture).

1. Installation

# Create virtual environment and install package in editable mode
python3 -m venv .venv
source .venv/bin/activate
pip install -e .

2. Quick Start

Extract frames and synchronized metadata

yuv-sensor --session_dir data/session_419864820

Export to COLMAP format with IMU-based pose priors

yuv-sensor --session_dir data/session_419864820 --export_colmap --colmap_output_dir output/colmap

For the full COLMAP walkthrough (feature extraction, matching, mapping, troubleshooting), see COLMAP Workflow.

For all command-line flags and defaults, see CLI Reference.

3. Core Features

• YUV Decoding: Decode raw YUV_420_888 frames using layout and stride metadata from frames.csv
• Camera Calibration: Apply lens distortion correction and sensor orientation rotation
• Multi-sensor Synchronization: Align camera frames, IMU (accel/gyro), and exposure metadata by nanosecond timestamps
• IMU-based Pose Estimation: Integrate accelerometer and gyroscope data to estimate initial camera trajectory
• COLMAP Integration: Export images and camera parameters in COLMAP-compatible format with pose priors for 3D reconstruction
• Kalibr Export: Export images, camchain.yaml, and imu.csv as input for Kalibr camera-IMU calibration
• Static IMU Trim + imu.yaml: Auto-trim motion off the edges of a static IMU capture and derive Kalibr's imu.yaml (noise_density / random_walk) from it via Allan variance
• Checkerboard Camera Calibration: Calibrate camera intrinsics directly from a checkerboard capture using OpenCV — no Kalibr/rosbag needed, a quick pre-check against session.json's own intrinsics

Documentation

• Data Specification: Session directory structure and metadata formats
• CLI Reference: All command-line flags and defaults
• COLMAP Workflow: End-to-end example with COLMAP integration
• Kalibr Workflow: End-to-end example for Kalibr camera-IMU calibration
• API Reference: Detailed module and class documentation