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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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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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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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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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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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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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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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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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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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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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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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) ...
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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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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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