Calibration Reader

This example shows how to read calibration data stored on device over XLink.

Similiar samples:

Setup

Please run the install script to download all required dependencies. Please note that this script must be ran from git context, so you have to download the depthai-python repository first and then run the script

git clone https://github.com/luxonis/depthai-python.git
cd depthai-python/examples
python3 install_requirements.py

For additional information, please follow installation guide

Source code

Also available on GitHub

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#!/usr/bin/env python3

import depthai as dai
import numpy as np
import sys
from pathlib import Path

# Connect Device
with dai.Device() as device:
    calibFile = str((Path(__file__).parent / Path(f"calib_{device.getMxId()}.json")).resolve().absolute())
    if len(sys.argv) > 1:
        calibFile = sys.argv[1]

    calibData = device.readCalibration()
    calibData.eepromToJsonFile(calibFile)

    M_rgb, width, height = calibData.getDefaultIntrinsics(dai.CameraBoardSocket.RGB)
    print("RGB Camera Default intrinsics...")
    print(M_rgb)
    print(width)
    print(height)

    M_rgb, width, height = calibData.getDefaultIntrinsics(dai.CameraBoardSocket.RGB)

    M_left = np.array(calibData.getCameraIntrinsics(dai.CameraBoardSocket.LEFT, 1280, 720))
    print("LEFT Camera resized intrinsics...")
    print(M_left)

    D_left = np.array(calibData.getDistortionCoefficients(dai.CameraBoardSocket.LEFT))
    print("LEFT Distortion Coefficients...")
    [print(name+": "+value) for (name, value) in zip(["k1","k2","p1","p2","k3","k4","k5","k6","s1","s2","s3","s4","τx","τy"],[str(data) for data in D_left])]

    M_right = np.array(calibData.getCameraIntrinsics(dai.CameraBoardSocket.RIGHT, 1280, 720))
    print("RIGHT Camera resized intrinsics...")
    print(M_right)

    D_right = np.array(calibData.getDistortionCoefficients(dai.CameraBoardSocket.RIGHT))
    print("RIGHT Distortion Coefficients...")
    [print(name+": "+value) for (name, value) in zip(["k1","k2","p1","p2","k3","k4","k5","k6","s1","s2","s3","s4","τx","τy"],[str(data) for data in D_right])]

    print(f"RGB FOV {calibData.getFov(dai.CameraBoardSocket.RGB)}, Mono FOV {calibData.getFov(dai.CameraBoardSocket.LEFT)}")

    R1 = np.array(calibData.getStereoLeftRectificationRotation())
    R2 = np.array(calibData.getStereoRightRectificationRotation())
    M_right = np.array(calibData.getCameraIntrinsics(calibData.getStereoRightCameraId(), 1280, 720))

    H_left = np.matmul(np.matmul(M_right, R1), np.linalg.inv(M_left))
    print("LEFT Camera stereo rectification matrix...")
    print(H_left)

    H_right = np.matmul(np.matmul(M_right, R1), np.linalg.inv(M_right))
    print("RIGHT Camera stereo rectification matrix...")
    print(H_right)

    lr_extrinsics = np.array(calibData.getCameraExtrinsics(dai.CameraBoardSocket.LEFT, dai.CameraBoardSocket.RIGHT))
    print("Transformation matrix of where left Camera is W.R.T right Camera's optical center")
    print(lr_extrinsics)

    l_rgb_extrinsics = np.array(calibData.getCameraExtrinsics(dai.CameraBoardSocket.LEFT, dai.CameraBoardSocket.RGB))
    print("Transformation matrix of where left Camera is W.R.T RGB Camera's optical center")
    print(l_rgb_extrinsics)

Also available on GitHub

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#include <cstdio>
#include <iostream>
#include <string>

// Inludes common necessary includes for development using depthai library
#include "depthai-shared/common/CameraBoardSocket.hpp"
#include "depthai-shared/common/EepromData.hpp"
#include "depthai/depthai.hpp"

void printMatrix(std::vector<std::vector<float>> matrix) {
    using namespace std;
    std::string out = "[";
    for(auto row : matrix) {
        out += "[";
        for(auto val : row) out += to_string(val) + ", ";
        out = out.substr(0, out.size() - 2) + "]\n";
    }
    out = out.substr(0, out.size() - 1) + "]\n\n";
    cout << out;
}

int main(int argc, char** argv) {
    using namespace std;

    // Connect Device
    dai::Device device;

    dai::CalibrationHandler calibData = device.readCalibration();
    // calibData.eepromToJsonFile(filename);
    std::vector<std::vector<float>> intrinsics;
    int width, height;

    cout << "Intrinsics from defaultIntrinsics function:" << endl;
    std::tie(intrinsics, width, height) = calibData.getDefaultIntrinsics(dai::CameraBoardSocket::RIGHT);
    printMatrix(intrinsics);

    cout << "Width: " << width << endl;
    cout << "Height: " << height << endl;

    cout << "Stereo baseline distance: " << calibData.getBaselineDistance() << " cm" << endl;

    cout << "Mono FOV from camera specs: " << calibData.getFov(dai::CameraBoardSocket::LEFT)
         << ", calculated FOV: " << calibData.getFov(dai::CameraBoardSocket::LEFT, false) << endl;

    cout << "Intrinsics from getCameraIntrinsics function full resolution:" << endl;
    intrinsics = calibData.getCameraIntrinsics(dai::CameraBoardSocket::RIGHT);
    printMatrix(intrinsics);

    cout << "Intrinsics from getCameraIntrinsics function 1280 x 720:" << endl;
    intrinsics = calibData.getCameraIntrinsics(dai::CameraBoardSocket::RIGHT, 1280, 720);
    printMatrix(intrinsics);

    cout << "Intrinsics from getCameraIntrinsics function 720 x 450:" << endl;
    intrinsics = calibData.getCameraIntrinsics(dai::CameraBoardSocket::RIGHT, 720);
    printMatrix(intrinsics);

    cout << "Intrinsics from getCameraIntrinsics function 600 x 1280:" << endl;
    intrinsics = calibData.getCameraIntrinsics(dai::CameraBoardSocket::RIGHT, 600, 1280);
    printMatrix(intrinsics);

    std::vector<std::vector<float>> extrinsics;

    cout << "Extrinsics from left->right test:" << endl;
    extrinsics = calibData.getCameraExtrinsics(dai::CameraBoardSocket::LEFT, dai::CameraBoardSocket::RIGHT);
    printMatrix(extrinsics);

    cout << "Extrinsics from right->left test:" << endl;
    extrinsics = calibData.getCameraExtrinsics(dai::CameraBoardSocket::RIGHT, dai::CameraBoardSocket::LEFT);
    printMatrix(extrinsics);

    cout << "Extrinsics from right->rgb test:" << endl;
    extrinsics = calibData.getCameraExtrinsics(dai::CameraBoardSocket::RIGHT, dai::CameraBoardSocket::RGB);
    printMatrix(extrinsics);

    cout << "Extrinsics from rgb->right test:" << endl;
    extrinsics = calibData.getCameraExtrinsics(dai::CameraBoardSocket::RGB, dai::CameraBoardSocket::RIGHT);
    printMatrix(extrinsics);

    cout << "Extrinsics from left->rgb test:" << endl;
    extrinsics = calibData.getCameraExtrinsics(dai::CameraBoardSocket::LEFT, dai::CameraBoardSocket::RGB);
    printMatrix(extrinsics);

    return 0;
}

Got questions?

We’re always happy to help with code or other questions you might have.