docs

VR180 Camera Integration Guide

This folder contains documents for building a VR180 camera.

A high-level overview is available in the overview.pptx.

1. Camera Hardware
   • See hardware.md for detailed guideline for choosing the right hardware.
   • For initial evaluation of the camera app, you may use an Android phone as a camera emulator.
2. Android Firmware
   • Android 9.0 or above is recommended.
   • A virtual stereo camera (left-Right-eye stitched image output) should be provided through the Android Camera2 API.
     • Implementation is NOT provided in this repo.
     • OEMs need to implement based on the hardware platform. Google's reference camera is built on the QCS605 platform.
     • If the virtual camera id is not 0, customize the id in CameraConfigurator class.
   • Real timestamps are needed for synchronizing data between image and IMU data. Synchronization is critical for producing high-quality VR180 videos.
   • It is recommended to pass CTS tests related to Camera2 API (and Bluetooth and WiFi if the camera needs connectivity to the VR180 companion app or Internet).
3. Camera App Integration
   • A reference implementation of the Camera App is provided in this repo. Customization is required for OEM-specific configurations.
   • The Camera App requires system-level permission to be fully functional. The APK file should be pushed to /system/priv-app/ and the native libraries (.so files) need to be pushed to /system/lib/ (or /system/lib64 depending on the architecture).
4. Camera Calibration.
   • VR180-specific camera calibration is required on a per-unit basis to generate the required metadata. The calibration tool is provided in the /tools folder. The Camera App has calibration recorder mode which can capture the required dataset.
   • Once calibration is completed, the output files should be saved to the camera's storage. It is recommended to store the calibration data under /persist partition. Customize the ProjectionMetadataProvider class for the actual location of the calibration data.
   • See calibration.md for instructions.
5. Validation Tool
   • Once proper hardware, firmware, and software are developed, and calibration is completed, the output photos and videos should be validated for file format and geometry.
   • The validation tool is provided in the /tools folder.
   • See validation.md for details.