Questions tagged [stereo-vision]
stereo vision is the extraction of 3D information from digital images, such as obtained by a CCD camera.
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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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Estimating extrinsic parameters in stereo vision via sensors
I have multiple (around 6) cameras with a distance of around 4 meters to each other filming an object and I want to reconstruct the 3D shape of it. The cameras are attached to tripods and thus can be ...
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How to compute estimated variance for each disparity value?
I am trying to implement the paper titled Free Space Computation Using Stochastic Occupancy Grids and Dynamic ProgrammingHerńan Badino, Uwe Franke, Rudolf Mester available at this link
The overview (...
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How to get an axis in camera coordinate system pybullet?
I am using pybullet to render a robot simulation. This robot have 2 joints and hence, 2 corresponding axes of rotation. I know that when I use getJointInfo on this ...
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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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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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Stereo Bundle Adjustment
When doing stereo based visual odometry and bundle adjustment how does the stereo constraint get factored into the photometric error?
Do you use the fact the second cameras location is known wrt the ...
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How does dense mapping/voxel occupancy grid map work with bundle adjustment?
When running for example some version of Orb Slam with stereo vision you're using sparse features for tracking but you can also infer a full depth map. I am curious how you use that full depth map to ...
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Calculating the depth in a general stereo vision system
When calculating the depth of a pixel using two cameras, most of the literature I have read describes stereo vision with the cameras having parallel optical axis as shown in the picture below. Because ...
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Uncontrolled drift of Visual Inertial Odometry
I'm trying to use the VINS-Fusion package to obtain odometry for a quadcopter. The primary sensor is an Intel Realsense D435i. I've calibrated the camera and IMU extrinsics using Kalibr. IMU ...
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How to find fundamental matrix based on other fundamental matrix and camera movement?
I am trying to speed up some multi-camera system that relies on calculation of fundamental matrices between each camera pair.
Please notice the following is pseudocode. ...
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Explanation of the epipolar constraint in stereo imaging
I am watching this video, in which the epipolar constraint is defined as
$x_l \cdot (x_l \times t)=0$
It means that the vector $x_l$ that passes through the observed point and the left camera origin ...
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Cheap global shutter cameras with external synchronization
Please recommend cameras for multi-camera setup satisfying the following conditions:
Relatively cheap (up to 100$ per camera).
Global shutter.
No filters on lenses or pixels.
Resolution of 1 MP or ...
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ROS Publish Stereo Image From 2 USB Cameras
I have two monocular USB cameras and I want to use ROS to make it a stereo camera. I am having a hard time finding a ROS package that consumes 2 monocular camera image streams and publishes a depth ...
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Use 2 Cameras as 1 Stereo Camera
I have one Picamera and one normal USB Webcam and would like to use them together as one stereo camera. Is this even possible as the 2 cameras aren't exactly the same? I would like to use them in ROS ...
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Ground based path generation from RGBD camera
How does one generate a trajectory for a ground vehicle using an RGBD camera? For a drone it's simpler since you're not constrained by having to move on the ground but it's not clear to me how ...
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Mono VIO vs. Stereo-Camera to recover Depth Information
I have a question. I have found some papers, where they use a Mono-VIO to recover depth of a scene. My question is:
Suppose I have a robot arm and attach a mono-VIO system to it. Then I move this arm ...
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Choosing cameras for stereo vision system?
I'm in the process of building a stereo vision system with YOLO detection. The system have to detect airplanes in far distance and also measure the depth from the airplane to the camera. I think ...
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Trajectory planning in unstructured environments
How is trajectory planning normally carried out in off-road/unstructured environments? In particular I'm interested in how stereo vision can be used to plot trajectories over obstacles - for example, ...
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Size of smallest feature from pixel depth resolution
How do I get the size in mm of the smallest feature a depth camera can detect?
Known variables are: distance from the target (for instance 1 meter), depth resolution in pixels (for instance 1280 x 720)...
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How can I calibrate 3 cameras without knowing global pose of the object & camera locations? How can I find the pose of each camera wrt the first one?
I have camera feed (in the form of RGB images) from 3 cameras with partially overlapping Field-of-view i.e. for the time stamp 0 to 100, I have total 300 frames or say synchronized 100 RGB frames for ...
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How is the depth estimation done in DTAM / LSD-SLAM (direct VSLAM)?
I know that DTAM and LSD-SLAM both employ the photometric error between two keyframes to estimate the image depth. But I don't know what the photometric error describes precisely.
In the DTAM paper, I ...
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Assistance in finding correct LIDAR for short-range object detection task [closed]
I am working on a task that involves finding a distance of a moving object going a static linear object, e.g a long pole. After trying some approaches (mostly involving stereo vision), I have come up ...
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Triangulation in Stereo-Vision?
I need some help in 3D Positioning system I'm trying to set up.
At the moment I am using 2 Calibrated cameras, my strategy is to place an AR Marker on the scene, identify the position of the AR Marker ...
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Single Camera + Laser Projector Triangulation
I want to combine a laser line projector (projects a laser plane) and a single web camera to determine the X, Y, Z position of the laser point. I am slightly confused as to how to use the fact that we ...
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Tracking 3D motion using a stereo camera
Assuming you have a fixed stereo camera, looking at a rigid object, what are the techniques used to track the object?
My google searches lead me to optical flow and similar algorithms, but I believe ...
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Disparity error in active light stereo systems?
Based on this relationship, if we have to estimate the 'disparity error' of a stereo system which uses active light on the scene - can we estimate the disparity error to be very small? According to ...
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Active Light Stereopsis: 1 Camera + Projector Vs. 2 Camera + Projector
What is the difference between using 1 Camera and a Projector and using 2 Cameras and a Projector for creating structure from motion?
Is it that if we use only 1 camera and a projector then we will ...
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Number of pixel comparison needed to establish correspondence
I am reading the paper titled Variable Baseline/Resolution Stereo David Gallup, Jan-Michael Frahm, Philippos Mordohai, Marc Pollefeys
Section 3 of the paper talks about the time complexity of the ...
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disparity error to x and y accuracy
This question talks about the depth error ($\Delta$Z) as a function of disparity error ($\Delta$D).
I want to do the same for X and ...
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How does structured light improve accuracy in stereo vision?
In my understanding, in order to improve accuracy for the estimation of depth with a stereo vision camera, patterns of light are projected into the scene, because the resulting texture makes it easier ...
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Questions about customized stereo camera
I am designing my robot and I have quite design issues with the available stereo cameras on a market.
For the prototype I am using ZED M but it is too expensive and quite large.
The question is, do ...
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Short range stereo vision
I am designing a stereo vision system for short depth range (15 cm to 35 cm) and I have some problems about baseline, focal length and depth range.
My application is to scan an animal tissue (meat, ...
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Stereo-Calibration with Variable focal cameras
Is it possible to perform stereo-calibration with cameras having variable focus? and if so, how is it done basically?
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Stereo Rectification when Extrinsics are known
Suppose I have two cameras $C_1$ and $C_2$ arranged in a stereo configuration. Let us assume that the camera is free of distortion with ideal intrinsics and that the camera extrinsics $R$ and $t$ are ...
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Tracking object in realtime using depth image stream from a RGBD camera
I have an Intel RealSense camera which can stream RGB and depth image. Using those information I want to track an object moving on a table top. More specifically, I want to know position $(x,y)$ and ...
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Setting up a Structured Light Stereo system
I am trying to get started with a stereo experiment and wanted to know the mistakes I might have made during the experiment. The goal is to calculate the depth map of an object using one light ...
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Trigger two usb cameras at the same time
I'm studyng stereo cameras, and I want to build one. I searched a lot in internet, and the opinions are quite different about this topic.
Basically, my question is:
Can I synchronize two usb ...
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How to set tag arguments of stereo camera plugin (libgazebo_ros_multicamera.so)?
I have some questions about how to use "libgazebo_ros_multicamera.so" plugin.
what does tag arguments mean ?
Some arguments are both set in and , for example distortion arguments like , ...
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Stereo vision setup to obtain depth map
I am currently working on a project that requires me to obtain depth information and point cloud map of objects in an indoor environment ( roughly twice the size of a normal room). I would like to ...
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Camera calibration sequence with ground truth data
I'm looking for a SLAM dataset (monocular or stereo) specifically with a checkerboard, meaning the camera always has a checkerboard in frame.
Most popular datasets provide calibration sequences, ...
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Depth sensing for a pick-and-place robot
I am supposed to design a pick-and-place robot. I have a prismatic joint to go down to a particular depth to pick an object which is located in 2D using computer vision. What is the recommended way to ...
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Accuracy of stereovision camera
I want to use stereovision to get 3D coordinates of a point in the camera's frame. Let's say, I can zoom in and click in the image to select my point of interest.
I want an accuracy of about 0.05 - 0....
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Effectiveness of visual odometry algorithms (CPU usage)
My robot needs to obtain visual odometry, with a condition that the used algorithm has to have as low computational requirements as possible and the used camera/sensor shouldn't be very expensive. The ...
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Forward monocular stereo vision (Structure from Motion)
I am looking for a library (or algorithm) that computes 3D scene (point cloud) from 2 consecutive images of a monocular sequence. I mean something like OpenSfM but only for 2 consecutive frames and ...
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Correct calibration parameters of stereo system due to vibrations
In stereo vision, the camera is calibrated using the popular chessboard before use. During the course of use, the camera maybe be subject to environmental factors such as vibrations.This may cause ...
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setup requirement of stereo camera
In the stereo camera system, two cameras are needed and should be mounted side by side. I see someone just glues two cameras to a wooden board. However one mobile phone manufacture claimed that the ...
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Effect of camera misalignment errors in dual cameras
In the camera module assembly process, parameters of camera modules vary due to manufacturing tolerance.
Camera calibration is performed to obtain actual parameters.
In the paper Effects of camera ...
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Is there a better way to deal with untextured regions in stereo matching
Texture is very helpful for stereo matching. However in real environment, untextured areas always exit. Consistent semi-global matching is proposed to deal with untextured regions. I start to read the ...
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Google's 'Tango' - How it works and what's special about the hardware?
I'm looking for a good breakdown and explanation of Google's 'Tango' AR platform. Specifically how the hardware works together to generate depth maps and the SDK's use of it.
I know the hardware ...
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