vignetting_calib

A useful tool for camera vignetting calibration

vignetting_calib us an offline camera vignetting calibration and correction tool. The calibration is easy with a chessboard in a light uniform environment.

Authors: Wenlaing GAO

Build

Prerequisites

ROS

ROS Kinetic on Ubuntu 16.04: ROS Installation.

Other ROS pacakge requisites: special version camera_model, code_utils.

For image ccollection, use calib_image_saver.

Ceres Solver

Follow Ceres-Solver Installation, remember to make install. (Our testing environment: Ubuntu 16.04, ROS Kinetic, OpenCV 3.2.0, Eigen 3.2.0)

Build VINS-OS

Clone the repository and catkin_make:

    cd TO-YOUR-ROS-CATKIN-WORKSPACE
    git clone [email protected]:gaowenliang/vignetting_calib.git
    cd ../
    catkin_make

Run with your device

1. camera intrinsic calibration

Collect chessboard images with calib_image_saver.

Calibrate the intrinsic parameters using the tool in camera_model.

2. vignetting calibration

Check the threshold between the black squares and the write squares. Finish

./vignetting_calib --camera-name wkx --input wkx/ -p IMG_ -e png -w 9 -h 8 --size 70 --opencv true --resize-scale 1.0 --cropper_width 0 --cropper_height 0 --center_x 640 --center_y 512 --save_result true --is_color false --threshold 45

If the threshold is right, the chessboard in the oputput images will be marked with green and red points.

the sample output

vignetting map:

sample parameter:

model_type: VIGNETTING
image_width: 1280
image_height: 960
center_x: 6.6464141845703125e+02
center_y: 4.7054119873046875e+02
is_color_cam: 0
channel: 1
vignetting_parameters:
   channel0:
      k0: 2.1326925528903553e+02
      k1: 3.2458047022269182e-05
      k2: -2.3826953130897426e-10
      k3: 0.

vignetting correction

Raw image:

correction image:

compared image: