I would like to request for a potential solution for my current problem. Currently I am tracking an aruco marker and moving the arm to that point, but the motion is not continuous (it's kind of jerky), is there methods that can be used to make the motion smoother. I am using MoveIt python API. Ultimate goal is to track object and later pick them from moving conveyor belts without using encoders.
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Many AR applications allow user to select a 3D object and display in the phone. If the user walks into a different area. The 3D object still remains at the same location. How can i achieve this? Can GPS solve this problem? But GPS is not accurate in indoor.
You can do it by using ARKit, ARCore or Vuforia SDKs. In ARKit and ARCore you can anchor objects to physical locations and they will stay there even if you walk into a different room. However, you might notice some drift in the location in ARCore because environmental understanding of device change over time or you might lose tracking at some point. With Vuforia you can use extended tracking to track objects but it is a bit different than ARCore and ARKit. You have to use ground plane or smart terrain to utilize extended tracking fully in your situation.
ARCore can track static surfaces according to its documentation, but doesn't mention anything about moving surfaces, so I'm wondering if ARCore can track flat surfaces (of course, with enough feature points) that can move around.
Yes, you definitely can track moving surfaces and moving objects in ARCore.
If you track static surface using ARCore – the resulted features are mainly suitable for so-called Camera Tracking. If you track moving object/surface – the resulted features are mostly suitable for Object Tracking.
You also can mask moving/not-moving parts of the image and, of course, inverse Six-Degrees-Of-Freedom (translate xyz and rotate xyz) camera transform.
Watch this video to find out how they succeeded.
Yes, ARCore tracks feature points, estimates surfaces, and also allows access to the image data from the camera, so custom computer vision algorithms can be written as well.
I guess it should be possible theoretically.
However, Ive tested it with some stuff in my HOUSE (running S8 and an app with unity and arcore)
and the problem is more or less that it refuses to even start tracking movable things like books and plates etc:
due to the feature points of the surrounding floor etc it always picks up on those first.
Edit: did some more testing and i Managed to get it to track a bed sheet, it does However not adjust to any movement. Meaning as of now the plane stays fixed allthough i saw some wobbling but i guess that Was because it tried to adjust the Positioning of the plane once it's original Feature points where moved.
I am new to computer vision, and need some advice on where to start.
The project is to estimate speed of a moving object(A) relative to the moving object(B) which is tracking it(A).
what should I need to do if I assume-
if the background is appeared to be static(making the background single colored)
if the background is moving (harder)
I want to do this using opencv and c++
Any advice on where to start, general steps would be very appreciated. Thanks in advance!
If your camera is attached to object B, first you will have to design an algorithm to detect and track object A. A simplified algorithm can be:
Loop the steps below:
Capture video frame from the camera.
If object A was not in the previous frame, detect object A (manual initialisation, detection using known features, etc.). Otherwise, track the object using the previous position and a tracking algorithm (openCV offers quite a few).
Detect and record the current location of the object in image coordinates.
Convert the location to real world coordinates.
If previous locations and timestamps for the object were available, calculate its speed.
The best way to do this is to get started with at least a simple C++ program that captures frames from a camera, and keep adding steps for detection and tracking.
I am totally new to AR and I searched on the internet about marker based and markerless AR but I am confused with marker based and markerless AR..
Lets assume an AR app triggers AR action when it scans specific images..So is this marker based AR or markerless AR..
Isn't the image a marker?
Also to position the AR content does marker based AR use devices' accelerometer and compass as in markerless AR?
In a marker-based AR application the images (or the corresponding image descriptors) to be recognized are provided beforehand. In this case you know exactly what the application will search for while acquiring camera data (camera frames). Most of the nowadays AR apps dealing with image recognition are marker-based. Why? Because it's much more simple to detect things that are hard-coded in your app.
On the other hand, a marker-less AR application recognizes things that were not directly provided to the application beforehand. This scenario is much more difficult to implement because the recognition algorithm running in your AR application has to identify patterns, colors or some other features that may exist in camera frames. For example if your algorithm is able to identify dogs, it means that the AR application will be able to trigger AR actions whenever a dog is detected in a camera frame, without you having to provide images with all the dogs in the world (this is exaggerated of course - training a database for example) when developing the application.
Long story short: in a marker-based AR application where image recognition is involved, the marker can be an image, or the corresponding descriptors (features + key points). Usually an AR marker is a black&white (square) image,a QR code for example. These markers are easily recognized and tracked => not a lot of processing power on the end-user device is needed to perform the recognition (and optionally tracking).
There is no need of an accelerometer or a compass in a marker-based app. The recognition library may be able to compute the pose matrix (rotation & translation) of the detected image relative to the camera of your device. If you know that, you know how far the recognized image is and how it is rotated relative to your device's camera. And from now on, AR begins... :)
Well. Since I got downvoted without explanation. Here is a little more detail on markerless tracking:
Actual there are several possibilities for augmented reality without "visual" markers but none of them called markerless tracking.
Showing of the virtual information can be triggered by GPS, Speech or simply turning on your phone.
Also, people tend to confuse NFT(Natural feature tracking) with markerless tracking. With NFT you can take a real life picture as a marker. But it is still a "marker".
This site has a nice overview and some examples for each marker:
Marker-Types
It's mostly in german but so beware.
What you call markerless tracking today is a technique best observed with the Hololens(and its own programming language) or the AR-Framework Kudan. Markerless Tracking doesn't find anything on his own. Instead, you can place an object at runtime somewhere in your field of view.
Markerless tracking is then used to keep this object in place. It's most likely uses a combination of sensor input and solving the SLAM( simultaneous localization and mapping) problem at runtime.
EDIT: A Little update. It seems the hololens creates its own inner geometric representation of the room. 3D-Objects are then put into that virtual room. After that, the room is kept in sync with the real world. The exact technique behind that seems to be unknown but some speculate that it is based on the Xbox Kinect technology.
Let's make it simple:
Marker-based augmented reality is when the tracked object is black-white square marker. A great example that is really easy to follow shown here: https://www.youtube.com/watch?v=PbEDkDGB-9w (you can try out by yourself)
Markerless augmented reality is when the tracked object can be anything else: picture, human body, head, eyes, hand or fingers etc. and on top of that you add virtual objects.
To sum it up, position and orientation information is the essential thing for Augmented Reality that can be provided by various sensors and methods for them. If you have that information accurate - you can create some really good AR applications.
It looks like there may be some confusion between Marker tracking and Natural Feature Tracking (NFT). A lot of AR SDK's tote their tracking as Markerless (NFT). This is still marker tracking, in that a pre-defined image or set of features is used. It's just not necessarily a black and white AR Toolkit type of marker. Vuforia, for example, uses NFT, which still requires a marker in the literal sense. Also, in the most literal sense, hand/face/body tracking is also marker tracking in that the marker is a shape. Markerless, inherent to the name, requires no pre-knowledge of the world or any shape or object be present to track.
You can read more about how Markerless tracking is achieved here, and see multiple examples of both marker-based and Markerless tracking here.
Marker based AR uses a Camera and a visual marker to determine the center, orientation and range of its spherical coordinate system. ARToolkit is the first full featured toolkit for marker based tracking.
Markerless Tracking is one of best methods for tracking currently. It performs active tracking and recognition of real environment on any type of support without using special placed markers. Allows more complex application of Augmented Reality concept.
I'm trying to develop an algorithm for real time tracking moving objects with a single moving camera setup as a project, in OpenCV (C++).
My basic objectives are
Detect motion in an (initially) static frame
Track that moving object (camera to follow that object)
Here is what I have tried already
Salient motion detection using temporal differencing and Optical Flow. (does not compensate for a moving camera)
KLT based feature tracking, but I was not able to segment the moving object features (moving object features got mixed with other trackable features in the image)
Mean shift based tracking (required initialization and is a bit computationally expensive)
I'm now trying to look into the following methods
Histogram of Gradients.
Algorithms that implement camera motion parameters.
Any advice on which direction should I proceed forward to acheive my objective.
Type: 'zdenek kalal predator' to google.com and watch the videos, read the papers that came up. I think it will give you a lot of insight.