Questions tagged [opencv]
OpenCV (Open Source Computer Vision) is a cross-platform library of programming functions for real time computer vision.
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Error when compiling cv_bridge in Raspberry Pi 4B with Raspbian buster and ROS Noetic
Im using Raspberry Pi 4B, with Raspbian Buster and ROS Noetic. When I tried to compile my catkin ws with a cv_bridge package I got the following error:
CMake Error at vision_opencv/cv_bridge/...
CommunityBot
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Converting a ros2 bag of color raw images to image files or video
This is using ros2 Humble in Ubuntu 22.04 and native Python 3.10
Eventual goal: capturing depth aligned RGB and Depth streams from Intel RealSense D435 camera and converting them to RGB and Depth ...
CommunityBot
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reading depth in mm from ros depth image
I want to read a depth image from ros.
I subscribe to the /camera/aligned_depth_to_color/image_raw/compressed topic published by a intel realsense D435i camera.
I ...
CommunityBot
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Need help in loading occupancy_grid map to OpenCV window
I have generated a map named map_1.pgm using map_server package. I want to display it in an ...
CommunityBot
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Calibration of camera using ROS, without camera info
As part of a college project, I need to communicate with a TM5-700 robotic arm developed by Omron, and implement, for now, a pick and place pipeline. For that, I am required to access the camera ...
CommunityBot
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I am trying to use opencv_cam pkg in ros2 humble with a csi stereo camera imx219-83 in a jetson nano and I get green screen
I am trying to use opencv_cam in ros2 humble for a csi stereo cam in a jetson nano. When I run the node : ros2 run opencv_cam opencv_cam_main ,it publishes the ...
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Switching between 2 cameras (using opencv)
I have a manipulator in ROS and 2 cameras attached on it.
I want to switch the frames of cameras every 5 seconds
Both cameras work fine.
I do not want to close the window and reopen it (if it is ...
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How do I use a CSI camera with ros?
I am using Jetson Orin Nano connected with raspberry Pi V2.0 Camera.
I am using gstreamer pipeline to get the camera feed. It works fine with g++ build and python but as soon as I try to build it with ...
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colorize area of point cloud on a 2D image
I am projecting a 3D Point Cloud on a 2D image incoming as ROS 2 messages. Now, I want to fill the gaps between pixels from the point cloud, so that I can see an area, instead of single pixels and ...
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Segmentation fault in cv::findContours call
I am struggling to debug a segmentation fault. Any help is appreciated! The node just crashes whenever I launch it and following is the seg fault I am getting when running through gdb:
...
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Implementing PID on a line following bot using turtlebot
I am using ROS melodic,turtlebot 2 on Ubuntu 18.04.
The idea is to create an environment consisting of lines as a path (slightly curved), and to program the turtlebot to follow the lines. Basically, a ...
CommunityBot
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How to use arbitrary version of OpenCV
Hi, i have ROS Kinetic installed and it comes with OpenCV. I also have the latested OpenCV that i downloaded from github and installed in /usr/local.
The following code that i wrote will always use ...
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OpenCV camera rvec tvec to ROS world pose
I'm detecting Aruco tags using the OpenCV bridge and I have tvec and rvec returned with the tag pose related to the camera using OpenCV axis notations. I would like convert them to a ROS pose related ...
CommunityBot
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Which single board computer should I chose?
Hi ros community
I' m working with ros to make a robot which can go itself with image proccessing. I am using lots of hardware in this project and I used pcduino V3 until this time. But I want to ...
CommunityBot
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multiple video streaming
I'm currently experimenting with video stream opencv. But,I think I can only stream one video at a time.Is it possible to stream multiple videos at the same time?If there are other packages that would ...
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Conversion from 32FC1 to mono8 using cv_bridge
I am trying to use cv_bridge to convert an image from /disp_map/image (32FC1 encoding according to msg->encoding ) to an ...
CommunityBot
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Detecting door blockage using computer vision
I want to detect door blockage on a camera. Basically if the exit door is blocked by an object, it detects it as an anomaly. How can we do it? Is it possible to do it using OpenCV?
Remember, it doesn’...
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Vision programming with OpenCV
I am currently working on a project on NiryoOne which requires facial detection of a person through NiryoOne camera (ELP SONY IMX).
The code that I am using works on my laptop running Ubuntu. However, ...
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Making sense of disparity values after applying `StereoSGBM` from OpenCV
I just started with Kitty Stereo Dataset (2015). The first thing I did was compute the disparity using the stereoSGBM class. And here is the rectified input images ...
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Trouble aligning/calibrating camera with laser scanner
I have a robot which has 2 multi-spectral cameras and 1 laser scanner attached. In the end I would like to have the images from the cameras aligned with the scanner so that I can have spectral ...
CommunityBot
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WEBOTS - Connect a external Tkinter Script to main controller?
I have a WEBOTS Simulation with an automobile. Now while WEBOTS provides a camera overlay, I want to display the result of image processing along with sensor data in a comprehensive manner.
For this I ...
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Marker pose flickering one axis from -4 to +18 when camera is not moving
I'm taking a sequence of frames from intel real sense and detecting april tags, I noticed the axis is flickering even camera is not moving. euler angle y axis is changing(visually and numerically) ...
Ben♦
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How can I change the dicitonary of aruco markers in aruco_ros package to the newer DICT_4x4 dictionary?
The arcuo_ros package by pal_electronics uses old dictionaries of aruco markers, the markers of these dictionaries are coded in uint64_t integer in the code file of the dictionaries dictionary.cpp (...
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Outlier rejection of fisheye stereo feature, how to do it?
OpenCV provides a nice outlier rejection feature with findFundamentalMat function. But that's for the pinhole projection model.
How do we detect the outliers around the edge of the image circle where ...
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Convert CameraInfo K & D to OpenCV format convenience functions?
Are there existing functions to convert from camera info arrays of K and D to intrinsic and distortion cv::Mats that can be passed into opencv functions like ...
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Configuring ROS2 for OpenCV and C++
How to properly setup the ROS2 workspace (i.e., cmakelists and package.xml, etc.) for using OpenCV and C++ ?
I could not find proper examples for that.
Thanks in advance.
Originally posted by ...
Werewolf_86
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How to enable GPU-Features of Rtabmap
OS: Ubuntu 20.04
CUDA 11.6, CuDNN 8.4 (GPU is Nvidia Quadro T 1000)
OpenCV 4.5.5 with GPU support also for CUDA and also the opencv_contribs
currently using Rtabmap standalone, but I intend to use the ...
TurBot
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CMake detects intended OpenCV+CUDA, but runtime does not use intended OpenCV version
CMakeLists.txt contains
...
MrOCW
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Catkin_make failed to build opencv
Hello guys,
I want to compile a package (https://github.com/mjshiggins/ros-examples) with the catkin_make command from the catkin_ws folder, but it seems that the OpenCV header file is depreceated or ...
Petros ADLATUS
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OpenCV and ROS2
I've checked all the related questions here and I still wasn't able to get this example to run. I apologize in advance if the solution was right in front of me and if that offended anyone.
Problem ...
mintybim
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Why would we solve AX=XB instead of just using the Kabsch algorithm?
I have a high precision stereo camera and a robot which are independent units (the camera is not mounted to the robot). I wish to compute a transformation from the camera frame to the robot base frame....
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ROS2: How to publish cv Mat image?
I'm having trouble understanding how to publish a cv::Mat image in C++, and I can find very little documentation about this.
Here's my publish code. I based it on this tutorial: https://docs.ros.org/...
zjeffer
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Determine the relative camera pose given two RGB camera frames in openCV-python
I would like to determine the relative camera pose given two RGB camera frames. I assume there's overlap in field of view between the two cameras, what I am looking for ultimately is the rotation and ...
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upgrade opencv version in melodic
Hello,
i want to upgrade opencv version to over 3.4 in Melodic.
Melodic installs opencv 3.2 originally,
so I tried to uninstall opencv 3.2, and re-install opencv 3.4
But some packages which are ...
danekim
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Noetic python raw Image publisher (from video)
Hi everyone,
I have spent nearly 2 full days with this problem now and have some extensive research, but just can't figure it out.
My apologies for being a burden, I ussually hesitate to waste anyones ...
USAotearoa
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9
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Image Subscriber Lags (despite queue_size=1 and buff_size=2**30)
Hi,
I have been working on a Python class that will allow me to spawn an object in gazebo, take an image of the object, and then delete that object, for a given number of objects that I provide. I am ...
jdastoor3
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ModuleNotFoundError: No module named 'cv_bridge' IN windows10 running foxy
I was following this tutorial https://automaticaddison.com/getting-started-with-opencv-in-ros-2-foxy-fitzroy-python/ to implement a simple ros2 image publisher and subscriber. everything was built but ...
aniketwagh
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Does a stable library exist for docking robots using images?
I built a mobile base from scratch, and now I am focused on getting the robot to charge.
The robot is using an on-board webcam (and PC) to detect a QR barcode on the charger unit. Using OpenCV I find ...
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What is the exact format and size of Image() object?
I cannot figure out what is the exact format of the sensor_msg Image() file. When I issue the command:
rostopic echo /camera/image_raw
I get a massive output ...
Tejas Rao
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1
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91
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Make robot drive as far from obstacles as possible
I am trying to make robot drive around the room, avoiding obstacles with pathfinding. The problem is I get few waypoints from pathfinding algorithm for robot to drive to (green dots), but it drive a ...
CommunityBot
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Pictures coordinates to robot coordinates
I have a picture on my C# software and the corresponding object in real world on 2d plane of motorized XY axis table. What I want is when I select a pixel on my picture, the motorized table should be ...
CommunityBot
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Reflective surface
Have you encountered the problem of reflective surfaces for realsense camera (d435 or t265) and lidar (A1 or A2). I would like to know what are the ways to solve problems with reflective surfaces for ...
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Compress Image topic with h264 streaming for low bandwidth connection?
Hello,
I faced the problem that sending the video with big resolution (1920x1080) is very difficult even with image transport. The raw or compressed images are too bit for sending over the network (...
Yehor
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9
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Find intrisic camera matrix from gazebo model
Hello,
I made a my camera model in gazebo and I want to extract the intrinsic matrix to use Opencv matrix.
Here is my model:
...
xavier12358
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316
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Path planning for robot car on grid
I am currently doing a project as my hobby. I am trying to simulate a robot car in a grid arena. Below is the image of the arena:
The start point of the car is the bottom-right corner(dark green ...
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169
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Eliminate grey space around the saved map
I have mapped my Gazebo environment using the slam_gmapping node. On running ...
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Finding OpenCV Paths in ROS Builds
Short version: How do I find the path to haarcascade_frontalface_alt.xml provided by opencv?
Long version:
I'm working on getting the ...
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Robotic Hand Grasp Planning - How do I find the initial contact point for each finger when grasping an object?
I am trying to design a robotic hand that is able to adaptively grasp unfamiliar objects. I am initially thinking that using OpenCV for pose estimation might make doing so easier.
Assuming that I am ...
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openCV transform datatypes to ROS msg tf/goal
Hi,
Iam looking for the best practice to make a openCV transform (getAffineTransform() ) into a pathplanner goal message (angle, translation). I dont really understand all the different datatypes used....
Dragonslayer
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4
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Problem viewing images using python-opencv
I have trouble viewing color images from R200 realsense camera using the python-opencv interface.
The window is blank when I run this script.
When I comment out'cv2.namedWindow("Image window"...
pnambiar