Yet Another Calibrator (YAC) is a calibration tool for calibrating RGB cameras. Specifically:
- Camera intrinsics
- Stereo camera intrinsics and extrinsics
- Mocap-marker to camera extrinsics
Supported projection-distortion models:
- pinhole-radtan4
- pinhole-equi4
# Ubuntu packages
libyaml-cpp-dev
libeigen3-dev
libceres-dev
libopencv-dev
libomp-dev (optional)
# Custom (see deps dir)
Modified apriltags (https://github.com/chutsu/apriltags)
For the lazy :
# The following assumes you have a catkin workspace at $HOME/catkin_ws
# If not edit the CATKIN_WS variable in the Makefile
git clone https://github.com/chutsu/yac
cd yac
make deps
make release
Or standard approach:
# Clone repo to your catkin workspace
cd <your catkin workspace>/src
git clone https://github.com/chutsu/yac
# Install dependencies
cd yac && make deps
# Build yac
catkin build -DCMAKE_BUILD_TYPE=Release yac yac_ros
# Note: Optimization will be very slow if not built in RELEASE mode.
yac uses a grid of AprilTags, a.k.a an AprilGrid, as a calibration target.
Click here to download and print the AprilGrid. During data collection make sure the calibration target is as flat as possible.
First inorder to calibrate a monocular camera or stereo camera pair we need to
create the calibration configuration file. For example calib_intel_d435i.yaml
configuration file:
ros:
bag: "/data/intel_d435i/imucam-1.bag"
cam0_topic: "/stereo/camera0/image"
calib_target:
target_type: 'aprilgrid' # Target type
tag_rows: 6 # Number of rows
tag_cols: 6 # Number of cols
tag_size: 0.088 # Size of apriltag, edge to edge [m]
tag_spacing: 0.3 # Ratio of space between tags to tagSize
# Example: tag_size=2m, spacing=0.5m
# --> tag_spacing=0.25[-]
cam0:
proj_model: "pinhole"
dist_model: "radtan4"
lens_hfov: 69.4
lens_vfov: 42.5
resolution: [640.0, 480.0]
rate: 30.0
cam1:
proj_model: "pinhole"
dist_model: "radtan4"
lens_hfov: 69.4
lens_vfov: 42.5
resolution: [640.0, 480.0]
rate: 30.0
The above tells yac where to find the rosbag containing the calibration data,
the calibration target and camera details. Now, we need to pass that to a yac
calibrator via the roslaunch file calib_mono.launch or calib_stereo.launch:
# To calibrate cam0 intrinsics only
roslaunch yac calib_mono.launch config_file:=<path to calib_intel_d435i.yaml>
# To calibrate stereo camera pair intrinsics and extrinsics
roslaunch yac calib_stereo.launch config_file:=<path to calib_intel_d435i.yaml>
MIT