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<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width,initial-scale=1">
<meta name="generator" content="VuePress 2.0.0-beta.38">
<style>
:root {
--c-bg: #fff;
}
html.dark {
--c-bg: #22272e;
}
html, body {
background-color: var(--c-bg);
}
</style>
<script>
const userMode = localStorage.getItem('vuepress-color-scheme');
const systemDarkMode = window.matchMedia && window.matchMedia('(prefers-color-scheme: dark)').matches;
if (userMode === 'dark' || (userMode !== 'light' && systemDarkMode)) {
document.documentElement.classList.toggle('dark', true);
}
</script>
<title>Working with the camera | Clover</title><meta name="description" content="Clover Drone Kit">
<link rel="modulepreload" href="/clover-vuepress/assets/app.4f6a4bec.js"><link rel="modulepreload" href="/clover-vuepress/assets/camera.html.9a2e1502.js"><link rel="modulepreload" href="/clover-vuepress/assets/camera.html.317dc821.js">
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</head>
<body>
<div id="app"><!--[--><div class="theme-container"><!--[--><header ref_key="navbar" class="navbar"><div class="toggle-sidebar-button" title="true" aria-expanded="false" role="button" tabindex="0"><div class="icon" aria-hidden="true"><span></span><span></span><span></span></div></div><span><a href="/clover-vuepress/en/" class=""><img class="logo" src="/clover-vuepress/clover-logo.png" alt="Clover"><span class="site-name can-hide">Clover</span></a></span><div class="navbar-items-wrapper" style=""><!--[--><!--]--><nav class="navbar-items can-hide"><!--[--><div class="navbar-item"><a class="external-link" href="https://coex.tech" rel="noopener noreferrer" target="_blank" aria-label="Official Site"><!--[--><!--]--> Official Site <span><svg class="external-link-icon" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewbox="0 0 100 100" width="15" height="15"><path fill="currentColor" 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xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewbox="0 0 100 100" width="15" height="15"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path><polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg><span class="external-link-icon-sr-only">open in new window</span></span><!--[--><!--]--></a></div><!--]--></nav><!--[--><!--]--><ul class="sidebar-items"><!--[--><li><a href="/clover-vuepress/en/" class="sidebar-item sidebar-heading" aria-label="COEX Clover"><!--[--><!--]--> COEX Clover <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/glossary.html" class="sidebar-item sidebar-heading" aria-label="Glossary"><!--[--><!--]--> Glossary <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/safety.html" class="sidebar-item sidebar-heading" aria-label="Safety tips"><!--[--><!--]--> Safety tips <!--[--><!--]--></a><!----></li><li><p tabindex="0" class="sidebar-item sidebar-heading collapsible">Assembly <span class="right arrow"></span></p><!--[--><ul style="display:none;" class="sidebar-item-children"><!--[--><li><a href="/clover-vuepress/en/assembly.html" class="sidebar-item" aria-label="Clover drone assembly"><!--[--><!--]--> Clover drone assembly <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/assemble_4_2.html" class="sidebar-item" aria-label="Clover 4.2 assembly"><!--[--><!--]--> Clover 4.2 assembly <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/assemble_4_2_ws.html" class="sidebar-item" aria-label="Clover 4 assembly"><!--[--><!--]--> Clover 4 assembly <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/assemble_4.html" class="sidebar-item" aria-label="Clover 4 assembly"><!--[--><!--]--> Clover 4 assembly <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/assemble_3.html" class="sidebar-item" aria-label="Assembly of Clover 3"><!--[--><!--]--> Assembly of Clover 3 <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/assemble_2.html" class="sidebar-item" aria-label="Clover 2 construction kit assembly instruction"><!--[--><!--]--> Clover 2 construction kit assembly instruction <!--[--><!--]--></a><!----></li><!--]--></ul><!--]--></li><li><p tabindex="0" class="sidebar-item sidebar-heading collapsible">Configuration <span class="right arrow"></span></p><!--[--><ul style="display:none;" class="sidebar-item-children"><!--[--><li><a href="/clover-vuepress/en/setup.html" class="sidebar-item" aria-label="Initial setup"><!--[--><!--]--> Initial setup <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/calibration.html" class="sidebar-item" aria-label="Sensor calibration"><!--[--><!--]--> Sensor calibration <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/radio.html" class="sidebar-item" aria-label="RC setup"><!--[--><!--]--> RC setup <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/rc_flysky_a8s.html" class="sidebar-item" aria-label="Using Flysky FS-A8S"><!--[--><!--]--> Using Flysky FS-A8S <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/modes.html" class="sidebar-item" aria-label="Flight modes"><!--[--><!--]--> Flight modes <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/power.html" class="sidebar-item" aria-label="Power setup"><!--[--><!--]--> Power setup <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/failsafe.html" class="sidebar-item" aria-label="Failsafe configuration"><!--[--><!--]--> Failsafe configuration <!--[--><!--]--></a><!----></li><!--]--></ul><!--]--></li><li><p tabindex="0" class="sidebar-item sidebar-heading collapsible">Manual flight <span class="right arrow"></span></p><!--[--><ul style="display:none;" class="sidebar-item-children"><!--[--><li><a href="/clover-vuepress/en/flight.html" class="sidebar-item" aria-label="Flight"><!--[--><!--]--> Flight <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/flight_exercises.html" class="sidebar-item" aria-label="Drone control exercises"><!--[--><!--]--> Drone control exercises <!--[--><!--]--></a><!----></li><!--]--></ul><!--]--></li><li><p tabindex="0" class="sidebar-item sidebar-heading collapsible">Working with Raspberry Pi <span class="right arrow"></span></p><!--[--><ul style="display:none;" class="sidebar-item-children"><!--[--><li><a href="/clover-vuepress/en/raspberry.html" class="sidebar-item" aria-label="Raspberry Pi"><!--[--><!--]--> Raspberry Pi <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/image.html" class="sidebar-item" aria-label="Raspberry Pi image"><!--[--><!--]--> Raspberry Pi image <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/wifi.html" class="sidebar-item" aria-label="Connecting to Clover via Wi-Fi"><!--[--><!--]--> Connecting to Clover via Wi-Fi <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/connection.html" class="sidebar-item" aria-label="Connecting Raspberry Pi to the flight controller"><!--[--><!--]--> Connecting Raspberry Pi to the flight controller <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/gcs_bridge.html" class="sidebar-item" aria-label="Using QGroundControl via Wi-Fi"><!--[--><!--]--> Using QGroundControl via Wi-Fi <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/ssh.html" class="sidebar-item" aria-label="SSH access to Raspberry Pi"><!--[--><!--]--> SSH access to Raspberry Pi <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/cli.html" class="sidebar-item" aria-label="Command line interface"><!--[--><!--]--> Command line interface <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/selfcheck.html" class="sidebar-item" aria-label="Automatic check"><!--[--><!--]--> Automatic check <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/web_video_server.html" class="sidebar-item" aria-label="Viewing images from cameras"><!--[--><!--]--> Viewing images from cameras <!--[--><!--]--></a><!----></li><!--]--></ul><!--]--></li><li><p tabindex="0" class="sidebar-item sidebar-heading active collapsible">Programming <span class="down arrow"></span></p><!--[--><ul style="" class="sidebar-item-children"><!--[--><li><a href="/clover-vuepress/en/programming.html" class="sidebar-item" aria-label="Programming"><!--[--><!--]--> Programming <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/camera_setup.html" class="sidebar-item" aria-label="Camera setup"><!--[--><!--]--> Camera setup <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/aruco.html" class="sidebar-item" aria-label="ArUco markers"><!--[--><!--]--> ArUco markers <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/aruco_marker.html" class="sidebar-item" aria-label="ArUco marker detection"><!--[--><!--]--> ArUco marker detection <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/aruco_map.html" class="sidebar-item" aria-label="Map-based navigation with ArUco markers"><!--[--><!--]--> Map-based navigation with ArUco markers <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/optical_flow.html" class="sidebar-item" aria-label="Use of Optical Flow"><!--[--><!--]--> Use of Optical Flow <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/simple_offboard.html" class="sidebar-item" aria-label="Autonomous flight"><!--[--><!--]--> Autonomous flight <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/frames.html" class="sidebar-item" aria-label="Coordinate systems (frames)"><!--[--><!--]--> Coordinate systems (frames) <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/snippets.html" class="sidebar-item" aria-label="Code examples"><!--[--><!--]--> Code examples <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/laser.html" class="sidebar-item" aria-label="Working with a laser rangefinder"><!--[--><!--]--> Working with a laser rangefinder <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/leds.html" class="sidebar-item" aria-label="Working with a LED strip"><!--[--><!--]--> Working with a LED strip <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/gpio.html" class="sidebar-item" aria-label="Working with GPIO"><!--[--><!--]--> Working with GPIO <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/sonar.html" class="sidebar-item" aria-label="Working with the ultrasonic distance gage"><!--[--><!--]--> Working with the ultrasonic distance gage <!--[--><!--]--></a><!----></li><li><a aria-current="page" href="/clover-vuepress/en/camera.html" class="router-link-active router-link-exact-active router-link-active sidebar-item active" aria-label="Working with the camera"><!--[--><!--]--> Working with the camera <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/rviz.html" class="sidebar-item" aria-label="Using rviz and rqt"><!--[--><!--]--> Using rviz and rqt <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/autolaunch.html" class="sidebar-item" aria-label="Software autorun"><!--[--><!--]--> Software autorun <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/javascript.html" class="sidebar-item" aria-label="Work with ROS from browser"><!--[--><!--]--> Work with ROS from browser <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/blocks.html" class="sidebar-item" aria-label="Blocks programming for Clover"><!--[--><!--]--> Blocks programming for Clover <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/simulation.html" class="sidebar-item" aria-label="Simulation overview"><!--[--><!--]--> Simulation overview <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/simulation_native.html" class="sidebar-item" aria-label="Native setup"><!--[--><!--]--> Native setup <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/simulation_vm.html" class="sidebar-item" aria-label="Simulation VM setup"><!--[--><!--]--> Simulation VM setup <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/simulation_usage.html" class="sidebar-item" aria-label="Using the simulator"><!--[--><!--]--> Using the simulator <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/simulation_m1.html" class="sidebar-item" aria-label="Running simulator on M1 powered computer"><!--[--><!--]--> Running simulator on M1 powered computer <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/ros.html" class="sidebar-item" aria-label="ROS"><!--[--><!--]--> ROS <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/mavros.html" class="sidebar-item" aria-label="MAVROS"><!--[--><!--]--> MAVROS <!--[--><!--]--></a><!----></li><!--]--></ul><!--]--></li><li><p tabindex="0" class="sidebar-item sidebar-heading collapsible">Supplementary materials <span class="right arrow"></span></p><!--[--><ul style="display:none;" class="sidebar-item-children"><!--[--><li><a href="/clover-vuepress/en/supplementary.html" class="sidebar-item" aria-label="Supplementary materials"><!--[--><!--]--> Supplementary materials <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/coex_pix.html" class="sidebar-item" aria-label="COEX Pix"><!--[--><!--]--> COEX Pix <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/coex_pdb.html" class="sidebar-item" aria-label="COEX PDB"><!--[--><!--]--> COEX PDB <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/coex_gps.html" class="sidebar-item" aria-label="COEX GPS"><!--[--><!--]--> COEX GPS <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/auto_setup.html" class="sidebar-item" aria-label="Step-by-step guide on autonomous flight with Clover 4"><!--[--><!--]--> Step-by-step guide on autonomous flight with Clover 4 <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/hostname.html" class="sidebar-item" aria-label="Hostname"><!--[--><!--]--> Hostname <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/sitl.html" class="sidebar-item" aria-label="PX4 Simulation"><!--[--><!--]--> PX4 Simulation <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/wall_aruco.html" class="sidebar-item" aria-label="Navigation using vertical ArUco-markers"><!--[--><!--]--> Navigation using vertical ArUco-markers <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/calibratePID.html" class="sidebar-item" aria-label="Configuring the PID coefficients"><!--[--><!--]--> Configuring the PID coefficients <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/models.html" class="sidebar-item" aria-label="Model files for parts"><!--[--><!--]--> Model files for parts <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/ros-install.html" class="sidebar-item" aria-label="ROS Melodic package installation and setup"><!--[--><!--]--> ROS Melodic package installation and setup <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/camera_calibration.html" class="sidebar-item" aria-label="Camera calibration"><!--[--><!--]--> Camera calibration <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/zerotire_vpn.html" class="sidebar-item" aria-label="Creating a virtual network ZeroTier One and connecting to it"><!--[--><!--]--> Creating a virtual network ZeroTier One and connecting to it <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/4g.html" class="sidebar-item" aria-label="Multi-copter control with 4G communication"><!--[--><!--]--> Multi-copter control with 4G communication <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/jetson_nano.html" class="sidebar-item" aria-label="Clover and Jetson Nano"><!--[--><!--]--> Clover and Jetson Nano <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/rc.html" class="sidebar-item" aria-label="Controlling Clover from a smartphone"><!--[--><!--]--> Controlling Clover from a smartphone <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/network.html" class="sidebar-item" aria-label="Configuring Wi-Fi"><!--[--><!--]--> Configuring Wi-Fi <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/uart.html" class="sidebar-item" aria-label="UART interface"><!--[--><!--]--> UART interface <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/parameters.html" class="sidebar-item" aria-label="PX4 Parameters"><!--[--><!--]--> PX4 Parameters <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/flight_logs.html" class="sidebar-item" aria-label="PX4 Logs and Topics"><!--[--><!--]--> PX4 Logs and Topics <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/firmware.html" class="sidebar-item" aria-label="Pixhawk / Pixracer firmware flashing"><!--[--><!--]--> Pixhawk / Pixracer firmware flashing <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/mavlink.html" class="sidebar-item" aria-label="MAVLink"><!--[--><!--]--> MAVLink <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/test_connection.html" class="sidebar-item" aria-label="How to use a multimeter?"><!--[--><!--]--> How to use a multimeter? <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/radioerrors.html" class="sidebar-item" aria-label="Possible radio failures"><!--[--><!--]--> Possible radio failures <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/esc_firmware.html" class="sidebar-item" aria-label="Flashing ESCs using BLHeliSuite"><!--[--><!--]--> Flashing ESCs using BLHeliSuite <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/arduino.html" class="sidebar-item" aria-label="Controlling the copter from Arduino"><!--[--><!--]--> Controlling the copter from Arduino <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/gps.html" class="sidebar-item" aria-label="Connecting GPS"><!--[--><!--]--> Connecting GPS <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/ir_sensors.html" class="sidebar-item" aria-label="Working with IR sensors on Raspberry Pi 3"><!--[--><!--]--> Working with IR sensors on Raspberry Pi 3 <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/fpv_clover_4_2.html" class="sidebar-item" aria-label="Installing and configuring FPV equipment"><!--[--><!--]--> Installing and configuring FPV equipment <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/fpv.html" class="sidebar-item" aria-label="Installation of FPV"><!--[--><!--]--> Installation of FPV <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/magnetic_grip.html" class="sidebar-item" aria-label="Assembling and setting up the electromagnetic gripper"><!--[--><!--]--> Assembling and setting up the electromagnetic gripper <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/mechanical_grip.html" class="sidebar-item" aria-label="Assembling and setting up a mechanical gripper"><!--[--><!--]--> Assembling and setting up a mechanical gripper <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/trainer_mode.html" class="sidebar-item" aria-label="FlySky Trainer mode settings"><!--[--><!--]--> FlySky Trainer mode settings <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/tinning.html" class="sidebar-item" aria-label="Blanching"><!--[--><!--]--> Blanching <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/connectortypes.html" class="sidebar-item" aria-label="Types of power connectors"><!--[--><!--]--> Types of power connectors <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/4in1.html" class="sidebar-item" aria-label="Connecting 4 in 1 ESCs"><!--[--><!--]--> Connecting 4 in 1 ESCs <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/tb.html" class="sidebar-item" aria-label="Soldering safety"><!--[--><!--]--> Soldering safety <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/leds_old.html" class="sidebar-item" aria-label="Working with a LED strip on Raspberry 3"><!--[--><!--]--> Working with a LED strip on Raspberry 3 <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/contributing.html" class="sidebar-item" aria-label="Contribution to Clover"><!--[--><!--]--> Contribution to Clover <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/packages.html" class="sidebar-item" aria-label="COEX packages repository"><!--[--><!--]--> COEX packages repository <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/migrate20.html" class="sidebar-item" aria-label="Migration to version 0.20"><!--[--><!--]--> Migration to version 0.20 <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/migrate22.html" class="sidebar-item" aria-label="Migration to version 0.22"><!--[--><!--]--> Migration to version 0.22 <!--[--><!--]--></a><!----></li><!--]--></ul><!--]--></li><li><p tabindex="0" class="sidebar-item sidebar-heading collapsible">Events <span class="right arrow"></span></p><!--[--><ul style="display:none;" class="sidebar-item-children"><!--[--><li><a href="/clover-vuepress/en/events.html" class="sidebar-item" aria-label="Events"><!--[--><!--]--> Events <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/copterhack2022.html" class="sidebar-item" aria-label="CopterHack 2022"><!--[--><!--]--> CopterHack 2022 <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/copterhack2021.html" class="sidebar-item" aria-label="CopterHack 2021"><!--[--><!--]--> CopterHack 2021 <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/copterhack2019.html" class="sidebar-item" aria-label="Copter Hack 2019"><!--[--><!--]--> Copter Hack 2019 <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/copterhack2018.html" class="sidebar-item" aria-label="Copter Hack 2018"><!--[--><!--]--> Copter Hack 2018 <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/copterhack2017.html" class="sidebar-item" aria-label="Copter Hack 2017"><!--[--><!--]--> Copter Hack 2017 <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/video_contest.html" class="sidebar-item" aria-label="Contest for the best educational video on assembly and configuration"><!--[--><!--]--> Contest for the best educational video on assembly and configuration <!--[--><!--]--></a><!----></li><li><a href="/clover-vuepress/en/educational_contests.html" class="sidebar-item" aria-label="Educational contests"><!--[--><!--]--> Educational contests <!--[--><!--]--></a><!----></li><!--]--></ul><!--]--></li><!--]--></ul><!--[--><!--]--></aside><!--]--><!--[--><main class="page"><!--[--><!--]--><div class="theme-default-content"><!--[--><h1 id="working-with-the-camera" tabindex="-1"><a class="header-anchor" href="#working-with-the-camera" aria-hidden="true">#</a> Working with the camera</h1><div class="custom-container tip"><p class="custom-container-title">TIP</p><p>In the image version <strong>0.20</strong> <code>clever</code> package was renamed to <code>clover</code>. See <a href="https://github.com/CopterExpress/clover/blob/v0.19/docs/en/camera.md" target="_blank" rel="noopener noreferrer">previous version of the article<span><svg class="external-link-icon" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewbox="0 0 100 100" width="15" height="15"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path><polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg><span class="external-link-icon-sr-only">open in new window</span></span></a> for older images.</p></div><p>Make sure the camera is enabled in the <code>~/catkin_ws/src/clover/clover/launch/clover.launch</code> file:</p><div class="language-xml ext-xml"><pre class="language-xml"><code><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>arg</span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>main_camera<span class="token punctuation">"</span></span> <span class="token attr-name">default</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>true<span class="token punctuation">"</span></span><span class="token punctuation">/></span></span>
</code></pre></div><p>Also make sure that <a href="/clover-vuepress/en/camera_setup.html" class="">position and orientation of the camera</a> is correct.</p><p>The <code>clover</code> service must be restarted after the launch-file has been edited:</p><div class="language-text ext-text"><pre class="language-text"><code>sudo systemctl restart clover
</code></pre></div><p>You may use rqt or <a href="/clover-vuepress/en/web_video_server.html" class="">web_video_server</a> to view the camera stream.</p><h2 id="troubleshooting" tabindex="-1"><a class="header-anchor" href="#troubleshooting" aria-hidden="true">#</a> Troubleshooting</h2><p>If the camera stream is missing, try using the <a href="https://www.raspberrypi.org/documentation/usage/camera/raspicam/raspistill.md" target="_blank" rel="noopener noreferrer"><code>raspistill</code><span><svg class="external-link-icon" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewbox="0 0 100 100" width="15" height="15"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path><polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg><span class="external-link-icon-sr-only">open in new window</span></span></a> utility to check whether the camera works.</p><p>First, stop the <code>clover</code> service:</p><div class="language-bash ext-sh"><pre class="language-bash"><code><span class="token function">sudo</span> systemctl stop clover
</code></pre></div><p>Then use <code>raspistill</code> to capture an image from the camera:</p><div class="language-bash ext-sh"><pre class="language-bash"><code>raspistill -o test.jpg
</code></pre></div><p>If it doesn't work, check the camera cable connections and the cable itself. Replace the cable if it is damaged. Also, make sure the camera screws don't touch any components on the camera board.</p><h2 id="camera-parameters" tabindex="-1"><a class="header-anchor" href="#camera-parameters" aria-hidden="true">#</a> Camera parameters</h2><p>Some camera parameters, such as image size, FPS cap, and exposure, may be configured in the <code>main_camera.launch</code> file. The list of supported parameters can be found <a href="https://github.com/OTL/cv_camera#parameters" target="_blank" rel="noopener noreferrer">in the cv_camera repository<span><svg class="external-link-icon" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewbox="0 0 100 100" width="15" height="15"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path><polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg><span class="external-link-icon-sr-only">open in new window</span></span></a>.</p><p>Additionally you can specify an arbitrary capture parameter using its <a href="https://docs.opencv.org/3.3.1/d4/d15/group__videoio__flags__base.html" target="_blank" rel="noopener noreferrer">OpenCV code<span><svg class="external-link-icon" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewbox="0 0 100 100" width="15" height="15"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path><polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg><span class="external-link-icon-sr-only">open in new window</span></span></a>. For example, add the following parameters to the camera node to set exposition manually:</p><div class="language-xml ext-xml"><pre class="language-xml"><code><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>param</span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>property_0_code<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>21<span class="token punctuation">"</span></span><span class="token punctuation">/></span></span> <span class="token comment"><!-- property code 21 is CAP_PROP_AUTO_EXPOSURE --></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>param</span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>property_0_value<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>0.25<span class="token punctuation">"</span></span><span class="token punctuation">/></span></span> <span class="token comment"><!-- property values are normalized as per OpenCV specs, even for "menu" controls; 0.25 means "use manual exposure" --></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>param</span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cv_cap_prop_exposure<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>0.3<span class="token punctuation">"</span></span><span class="token punctuation">/></span></span> <span class="token comment"><!-- set exposure to 30% of maximum value --></span>
</code></pre></div><h2 id="computer-vision" tabindex="-1"><a class="header-anchor" href="#computer-vision" aria-hidden="true">#</a> Computer vision</h2><p>The <a href="/clover-vuepress/en/image.html" class="">SD card image</a> comes with a preinstalled <a href="https://opencv.org" target="_blank" rel="noopener noreferrer">OpenCV<span><svg class="external-link-icon" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewbox="0 0 100 100" width="15" height="15"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path><polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg><span class="external-link-icon-sr-only">open in new window</span></span></a> library, which is commonly used for various computer vision-related tasks. Additional libraries for converting from ROS messages to OpenCV images and back are preinstalled as well.</p><h3 id="python" tabindex="-1"><a class="header-anchor" href="#python" aria-hidden="true">#</a> Python</h3><p>Main article: <a href="http://wiki.ros.org/cv_bridge/Tutorials/ConvertingBetweenROSImagesAndOpenCVImagesPython" target="_blank" rel="noopener noreferrer">http://wiki.ros.org/cv_bridge/Tutorials/ConvertingBetweenROSImagesAndOpenCVImagesPython<span><svg class="external-link-icon" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewbox="0 0 100 100" width="15" height="15"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path><polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg><span class="external-link-icon-sr-only">open in new window</span></span></a>.</p><p>An example of creating a subscriber for a topic with an image from the main camera for processing with OpenCV:</p><div class="language-python ext-py"><pre class="language-python"><code><span class="token keyword">import</span> rospy
<span class="token keyword">import</span> cv2
<span class="token keyword">from</span> sensor_msgs<span class="token punctuation">.</span>msg <span class="token keyword">import</span> Image
<span class="token keyword">from</span> cv_bridge <span class="token keyword">import</span> CvBridge
rospy<span class="token punctuation">.</span>init_node<span class="token punctuation">(</span><span class="token string">'computer_vision_sample'</span><span class="token punctuation">)</span>
bridge <span class="token operator">=</span> CvBridge<span class="token punctuation">(</span><span class="token punctuation">)</span>
<span class="token keyword">def</span> <span class="token function">image_callback</span><span class="token punctuation">(</span>data<span class="token punctuation">)</span><span class="token punctuation">:</span>
cv_image <span class="token operator">=</span> bridge<span class="token punctuation">.</span>imgmsg_to_cv2<span class="token punctuation">(</span>data<span class="token punctuation">,</span> <span class="token string">'bgr8'</span><span class="token punctuation">)</span> <span class="token comment"># OpenCV image</span>
<span class="token comment"># Do any image processing with cv2...</span>
image_sub <span class="token operator">=</span> rospy<span class="token punctuation">.</span>Subscriber<span class="token punctuation">(</span><span class="token string">'main_camera/image_raw'</span><span class="token punctuation">,</span> Image<span class="token punctuation">,</span> image_callback<span class="token punctuation">)</span>
rospy<span class="token punctuation">.</span>spin<span class="token punctuation">(</span><span class="token punctuation">)</span>
</code></pre></div><p>To debug image processing, you can publish a separate topic with the processed image:</p><div class="language-python ext-py"><pre class="language-python"><code>image_pub <span class="token operator">=</span> rospy<span class="token punctuation">.</span>Publisher<span class="token punctuation">(</span><span class="token string">'~debug'</span><span class="token punctuation">,</span> Image<span class="token punctuation">)</span>
</code></pre></div><p>Publishing the processed image (at the end of the image_callback function):</p><div class="language-python ext-py"><pre class="language-python"><code>image_pub<span class="token punctuation">.</span>publish<span class="token punctuation">(</span>bridge<span class="token punctuation">.</span>cv2_to_imgmsg<span class="token punctuation">(</span>cv_image<span class="token punctuation">,</span> <span class="token string">'bgr8'</span><span class="token punctuation">)</span><span class="token punctuation">)</span>
</code></pre></div><p>The obtained images can be viewed using <a href="/clover-vuepress/en/web_video_server.html" class="">web_video_server</a>.</p><h4 id="retrieving-one-frame" tabindex="-1"><a class="header-anchor" href="#retrieving-one-frame" aria-hidden="true">#</a> Retrieving one frame</h4><p>It's possibly to retrieve one camera frame at a time. This method works slower than normal topic subscribing and should not be used when it's necessary to process camera images continuously.</p><div class="language-python ext-py"><pre class="language-python"><code><span class="token keyword">import</span> rospy
<span class="token keyword">from</span> sensor_msgs<span class="token punctuation">.</span>msg <span class="token keyword">import</span> Image
<span class="token keyword">from</span> cv_bridge <span class="token keyword">import</span> CvBridge
rospy<span class="token punctuation">.</span>init_node<span class="token punctuation">(</span><span class="token string">'computer_vision_sample'</span><span class="token punctuation">)</span>
bridge <span class="token operator">=</span> CvBridge<span class="token punctuation">(</span><span class="token punctuation">)</span>
<span class="token comment"># ...</span>
<span class="token comment"># Retrieve a frame:</span>
img <span class="token operator">=</span> bridge<span class="token punctuation">.</span>imgmsg_to_cv2<span class="token punctuation">(</span>rospy<span class="token punctuation">.</span>wait_for_message<span class="token punctuation">(</span><span class="token string">'main_camera/image_raw'</span><span class="token punctuation">,</span> Image<span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token string">'bgr8'</span><span class="token punctuation">)</span>
</code></pre></div><h3 id="examples" tabindex="-1"><a class="header-anchor" href="#examples" aria-hidden="true">#</a> Examples</h3><h4 id="working-with-qr-codes" tabindex="-1"><a class="header-anchor" href="#working-with-qr-codes" aria-hidden="true">#</a> Working with QR codes</h4><div class="custom-container tip"><p class="custom-container-title">TIP</p><p>For high-speed recognition and positioning, it is better to use <a href="/clover-vuepress/en/aruco.html" class="">ArUco markers</a>.</p></div><p>To program actions of the copter for the detection of <a href="https://en.wikipedia.org/wiki/QR_code" target="_blank" rel="noopener noreferrer">QR codes<span><svg class="external-link-icon" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewbox="0 0 100 100" width="15" height="15"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path><polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg><span class="external-link-icon-sr-only">open in new window</span></span></a> you can use the <a href="https://pypi.org/project/pyzbar/" target="_blank" rel="noopener noreferrer">pyZBar<span><svg class="external-link-icon" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewbox="0 0 100 100" width="15" height="15"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path><polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg><span class="external-link-icon-sr-only">open in new window</span></span></a>. This lib is installed in the last image for Raspberry Pi.</p><p>QR codes recognition in Python:</p><div class="language-python ext-py"><pre class="language-python"><code><span class="token keyword">import</span> rospy
<span class="token keyword">from</span> pyzbar <span class="token keyword">import</span> pyzbar
<span class="token keyword">from</span> cv_bridge <span class="token keyword">import</span> CvBridge
<span class="token keyword">from</span> sensor_msgs<span class="token punctuation">.</span>msg <span class="token keyword">import</span> Image
bridge <span class="token operator">=</span> CvBridge<span class="token punctuation">(</span><span class="token punctuation">)</span>
rospy<span class="token punctuation">.</span>init_node<span class="token punctuation">(</span><span class="token string">'barcode_test'</span><span class="token punctuation">)</span>
<span class="token comment"># Image subscriber callback function</span>
<span class="token keyword">def</span> <span class="token function">image_callback</span><span class="token punctuation">(</span>data<span class="token punctuation">)</span><span class="token punctuation">:</span>
cv_image <span class="token operator">=</span> bridge<span class="token punctuation">.</span>imgmsg_to_cv2<span class="token punctuation">(</span>data<span class="token punctuation">,</span> <span class="token string">'bgr8'</span><span class="token punctuation">)</span> <span class="token comment"># OpenCV image</span>
barcodes <span class="token operator">=</span> pyzbar<span class="token punctuation">.</span>decode<span class="token punctuation">(</span>cv_image<span class="token punctuation">)</span>
<span class="token keyword">for</span> barcode <span class="token keyword">in</span> barcodes<span class="token punctuation">:</span>
b_data <span class="token operator">=</span> barcode<span class="token punctuation">.</span>data<span class="token punctuation">.</span>decode<span class="token punctuation">(</span><span class="token string">"utf-8"</span><span class="token punctuation">)</span>
b_type <span class="token operator">=</span> barcode<span class="token punctuation">.</span><span class="token builtin">type</span>
<span class="token punctuation">(</span>x<span class="token punctuation">,</span> y<span class="token punctuation">,</span> w<span class="token punctuation">,</span> h<span class="token punctuation">)</span> <span class="token operator">=</span> barcode<span class="token punctuation">.</span>rect
xc <span class="token operator">=</span> x <span class="token operator">+</span> w<span class="token operator">/</span><span class="token number">2</span>
yc <span class="token operator">=</span> y <span class="token operator">+</span> h<span class="token operator">/</span><span class="token number">2</span>
<span class="token keyword">print</span><span class="token punctuation">(</span><span class="token string">"Found {} with data {} with center at x={}, y={}"</span><span class="token punctuation">.</span><span class="token builtin">format</span><span class="token punctuation">(</span>b_type<span class="token punctuation">,</span> b_data<span class="token punctuation">,</span> xc<span class="token punctuation">,</span> yc<span class="token punctuation">)</span><span class="token punctuation">)</span>
image_sub <span class="token operator">=</span> rospy<span class="token punctuation">.</span>Subscriber<span class="token punctuation">(</span><span class="token string">'main_camera/image_raw'</span><span class="token punctuation">,</span> Image<span class="token punctuation">,</span> image_callback<span class="token punctuation">,</span> queue_size<span class="token operator">=</span><span class="token number">1</span><span class="token punctuation">)</span>
rospy<span class="token punctuation">.</span>spin<span class="token punctuation">(</span><span class="token punctuation">)</span>
</code></pre></div><p>The script will take up to 100% CPU capacity. To slow down the script artificially, you can use <a href="http://wiki.ros.org/topic_tools/throttle" target="_blank" rel="noopener noreferrer">throttling<span><svg class="external-link-icon" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewbox="0 0 100 100" width="15" height="15"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path><polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg><span class="external-link-icon-sr-only">open in new window</span></span></a> of frames from the camera, for example, at 5 Hz (<code>main_camera.launch</code>):</p><div class="language-xml ext-xml"><pre class="language-xml"><code><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>node</span> <span class="token attr-name">pkg</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>topic_tools<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cam_throttle<span class="token punctuation">"</span></span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>throttle<span class="token punctuation">"</span></span>
<span class="token attr-name">args</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>messages main_camera/image_raw 5.0 main_camera/image_raw_throttled<span class="token punctuation">"</span></span><span class="token punctuation">/></span></span>
</code></pre></div><p>The topic for the subscriber in this case should be changed for <code>main_camera/image_raw_throttled</code>.</p><h2 id="video-recording" tabindex="-1"><a class="header-anchor" href="#video-recording" aria-hidden="true">#</a> Video recording</h2><p>To record a video you can use <a href="http://wiki.ros.org/image_view#image_view.2Fdiamondback.video_recorder" target="_blank" rel="noopener noreferrer"><code>video_recorder</code><span><svg class="external-link-icon" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewbox="0 0 100 100" width="15" height="15"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path><polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg><span class="external-link-icon-sr-only">open in new window</span></span></a> node from <code>image_view</code> package:</p><div class="language-bash ext-sh"><pre class="language-bash"><code>rosrun image_view video_recorder image:<span class="token operator">=</span>/main_camera/image_raw
</code></pre></div><p>The video file will be saved to a file <code>output.avi</code>. The <code>image</code> argument contains the name of the topic to record.</p><!--]--></div><footer class="page-meta"><div class="meta-item edit-link"><a class="external-link meta-item-label" href="https://github.com/CopterExpress/clover/edit/master/docs/en/camera.md" rel="noopener noreferrer" target="_blank" aria-label="Edit this page"><!--[--><!--]--> Edit this page <span><svg class="external-link-icon" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewbox="0 0 100 100" width="15" height="15"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path><polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg><span class="external-link-icon-sr-only">open in new window</span></span><!--[--><!--]--></a></div><!----><!----></footer><nav class="page-nav"><p class="inner"><span class="prev"><a href="/clover-vuepress/en/sonar.html" class="" aria-label="Working with the ultrasonic distance gage"><!--[--><!--]--> Working with the ultrasonic distance gage <!--[--><!--]--></a></span><span class="next"><a href="/clover-vuepress/en/rviz.html" class="" aria-label="Using rviz and rqt"><!--[--><!--]--> Using rviz and rqt <!--[--><!--]--></a></span></p></nav><!--[--><!--]--></main><!--]--></div><!----><!--]--></div>
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