Questions tagged [opencv]
OpenCV (Open Source Computer Vision) is a cross-platform library of programming functions for real time computer vision.
30 questions with no upvoted or accepted answers
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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 ...
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How do I use the live video stream from my arduino camera (connected by serial), to run with my OpenCV python ball tracking code?
My objective is to have the arduino camera, just to act like a webcam, and have my laptop run a ball tracking script on it. The ball tracking script already works with my laptops camera, and it can ...
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Maintaining scale factor for essential matrix
I want to recover the trajectory of a vehicle using a monocular camera via the computation of the essential matrix between t-1 and ...
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Difficulties transforming binary mask from camera frame to world frame
I have 2 RGB cameras in Gazebo11 looking at the same scene from different locations. I threshold the floor space and create a binary mask with white being the ground (free space) and black being ...
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cv2.stereoRectify works only when the rotation and translation are from camera 2 to camera 1
I am using the euroc-mav dataset to create a disparity map from stereo images: https://projects.asl.ethz.ch/datasets/doku.php?id=kmavvisualinertialdatasets.
In this dataset the cameras are already ...
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ArUco Markers Distance Estimation Accuracy Difference
The distance estimated (in cm: Because input size of ArUco Markers in cm too) using the code line after importing math module:
...
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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 ...
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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 ...
veilkrand
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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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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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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/...
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Interpreting results from Camera Calibration?
I used OpenCV's findChessboardCorners on a few checkerboard images (40~) and about 27 seemed to find the corners accurately. How does one proceed from here? Do I calculate the reprojection error over ...
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Are homogeneous coordinates represented by appending image coordinates with a 1 in camera imaging
In camera imaging, there are several terms for point coordinates.
World coordinates: [X, Y, Z] in physical unit
Image coordinates: [u, v] in pixel.
Do these coordinates become homogeneous ...
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Estimate 3D location of a tracked point with Known Camera parameters and Distance
I want to estimate the 3D point of X̅₂,
X̅₂ = [ X₂ Y₂ Z₂ ],
by using known variables:
X̅₁ is at world origin,
camera intrinsics K,
camera extrinsics w.r.t. X̅₁, namely [R₁ ∣ t₁],
...
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cv_bridge.h not found ROS2
I need cv_bridge on my cmakelist.txt. Cmakelist shows a path for cv_bridge.h, however there is no file on that name at that path.
I have opencv 4.5.4,ros2 humble.
I tried to install cv_bridge by ...
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ROS Melodic ORB SLAM 2 Map point vector is empty
I am trying to run ORB SLAM 2 with frames being published of a video I need to map however all parameters I have tried have lead to no features being detected even with some aggressive parameters as ...
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Nvidia Isaac ROS Visual SLAM with OpenCV
Hey Robotics Community,
i successfully completed the Tutorial for Visual SLAM:
https://nvidia-isaac-ros.github.io/concepts/visual_slam/cuvslam/tutorial_isaac_sim.html
Now i want to show the colorful ...
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AttributeError when trying to reinsert modified images into ROS2 bag file with Python
I'm currently working with ROS2 and Python to process image data stored in a ROS2 bag file. My task involves extracting images from the bag, performing modifications, and then reinserting them. I am ...
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Create self-contained standalone ROS1 application for Windows
I created a ROS Noetic package that grabs data from some cameras and performs pose estimation of objects in the field of view (using OpenCV). Simultaneously, IMU data is measured and fused with these ...
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Calculate disparity for matching feature points
If I have matched a pair of feature points, could I calculate its disparity by simply subtract the u coordinates(uL - uR)? And could use this disparity to calculate the depth for this 3d point?
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i want to run an image publisher in ros2 using opencv but this error apppears i am working with ros2 humble
when i run this qrie@qrie-HP-Laptop-15-rb0xx:~/dev_ws$ ros2 run cv_basics img_publisher
i get this error ModuleNotFoundError: No module named 'rclpy._rclpy_pybind11'
The C extension '/opt/ros/humble/...
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166
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Error: Could not demultiplex stream video player opencv depth camera
Video player gives "could not demultiplex stream"
...
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opencv StereoSGBM disparity parameters
In my setting I am using a stereo camera which has a baseline of b = 0.092m and a focal lenght in pixels of fx = 256.667.
So that when I want to constrain my setup to detect points up to a maximum ...
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14
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0
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ROS2 CV2 imshow and publish in the same loop fails
I attempted to publish and display an image from a video using cv2 and ros2. Although the code compiled successfully, running it consistently resulted in a memory allocation failure. Could someone ...
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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 ...
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154
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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 ...
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100
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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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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 ...
baseroguzhan
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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 ...
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