Is it possible to import a virtual lamp object into the AR scene, that projects a light cone, which illuminates the surrounding space in the room and the real objects in it, e.g. a table, floor, walls?
For ARKit, I found this SO post.
For ARCore, there is an example of relighting technique. And this source code.
I have also been suggested that post-processing can be used to brighten the whole scene.
However, these examples are from a while ago and perhaps threre is a newer or a more straight forward solution to this problem?
At the low level, RealityKit is only responsible for rendering virtual objects and overlaying them on top of the camera frame.
If you want to illuminate the real scene, you need to post-process the camera frame.
Here are some tutorials on how to do post-processing:
Tutorial1⃣️
Tutorial2⃣️
If all you need is an effect like This , then all you need to do is add a CGImage-based post-processing effect for the virtual object (lights).
More specifically, add a bloom filter to the rendered image(You can also simulate bloom filters with Gaussian blur).
In this way, the code is all around UIImage and CGImage, so it's pretty simple😎
If you want to be more realistic, consider using the depth map provided by LiDAR to calculate which areas can be illuminated for a more detailed brightness.
Or If you're a true explorer, you can use Metal to create a real world Digital Twin point cloud in real time to simulate occlusion of light.
There's nothing new in relighting techniques based on 3D compositing principles in 2021. At the moment, when you're working with RealityKit or SceneKit, you have to personally implement the relighting functionality with the help of two additional render passes (RGB pass is always needed) - Normals pass and PointPosition pass. Both AOVs must be 32-bit.
However, in the near future, when Apple engineers finally implement texture capturing in Scene Reconstruction – any inexperienced AR developer will be able to apply a relighting procedure.
Watch this Vimeo Video to find out how relighting can be achieved in The Foundry NUKE.
A crucial point here, when implementing the Relighting effect, is the presence of a LiDAR scanner (or iToF sensor if you're using ARCore). In other words, today's relighting solution for iOS is Metal + RealityKit.
Related
Think if someone in real life waved their hand and hit the 3D object in AR, how would I detect that? I basically want to know when something crosses over the AR object so I can know that something "hit" it and react.
Another example would be to place a virtual bottle on the table and then wave your hand in the air where the bottle is and then it gets knocked over.
Can this be done? If so how? I would prefer unity help but if this can only be done via Xcode and ARKit natively, I would be open to that as well.
ARKit does solve a ton of issues with AR and make them a breeze to work with. Your issue just isn't one of them.
As #Draco18s notes (and emphasizes well with the xkcd link 👍), you've perhaps unwittingly stepped into the domain of hairy computer vision problems. You have some building blocks to work with, though: ARKit provides pixel buffers for each video frame, and the projection matrix needed for you to work out what portion of the 2D image is overlaid by your virtual water bottle.
Deciding when to knock over the water bottle is then a problem of analyzing frame-to-frame differences over time in that region of the image. (And tracking that region's movement relative to the whole camera image, since the user probably isn't holding the device perfectly still.) The amount of of analysis required varies depending on the sophistication of effect you want... a simple pixel diff might work (for some value of "work"), or there might be existing machine learning models that you could put together with Vision and Core ML...
You should take a look at ManoMotion: https://www.manomotion.com/
They're working on this issue and suppose to release a solution in form of library soon.
I am not an ios developer but my client wants me to make an iphone app like
https://itunes.apple.com/us/app/trippy-booth-amazing-filterswarps/id448037560?mt=8
I have seen some custom library like
https://github.com/BradLarson/GPUImage
but do not find any camera lens customization example.
any kind of suggestions would be helpful
Thanks in advance
You can do it through some custom shader written in OpenGL(or metal just for iOS), then you can apply your shader to do interesting stuff like the image in above link.
I suggest you take a look at how to use the OpenGL framework in iOS.
Basically the flow would like:
Use whatever framework to capture(even in real time) a image.
Use some framework to modify the image. (The magic occur here)
Use another stuff to present the image.
You should learn how to obtain a OpenGL context, draw a image on it, write a custom shader, apply the shader, get the output, to "distort the image". For real, the hardest part is how to create that "effect" in your mind by describing it using a formula.
This is quite similar to the photoshop mesh warp (Edit->Transform->Warp). Basically you treat your image as a texture and then you render it on to a mesh (Bezier Patch) that is a grid that has been distorted into bezier curves, but you leave the texture coordinates as if it was still a grid. This has the effect of "pulling" the image towards the nodes of the patch. You can use OpenGL (GL_PATCHES) for this; I imagine metal or sceneKit might work as well.
I can't tell from the screen shots but its possible that the examples you reference are actually placing their mesh based on facial recognition. CoreImage has basic facial recognition to give youth out and eye positions which you could use to control some of the nodes in your mesh.
I am working on iOS Augmented Reality project, Where i need to integrate virtual dressing concept.
I tried OpenCV, it worked as desired for me in Face Detection Scenario Only but when i did Upper Body Portion, That didn't work for me as desired.
I used UPPER_BODY_HAAR_CASCADE but it didn't work as it was desired
it came as something like
but my desired output is something like this
If someone has achieved this functionality in iOS, Please Reply me
Not exactly answer you are looking for. You make your app depending on the sdk you choose. Most of them are quite expensive to use and may suffer from changing the use policy. Additionally you drag all the extensive functionality you don't need into your app. So at the end of day your app is 60-100MB in size.
If I was you (and I was in similar situation), I would develop own little sdk with the functionality you need. If you know how to do it then it takes couple days for the basic things to work. Plus opencv and you are in good shape.
PS. #Tommy asked interesting question. How one can approach to implement something like on this video: youtube.com/watch?v=IBE11ROpxHE
Adding some info which is too long for comment.
#Tommy Nice video. It seems to have all we need to proceed. First of all, for any AR application you need your camera (mobile phone camera) calibration info. In simple case, it contains two matrixes: camera matrix and distortion matrix. Camera matrix is then used for creating opengl projection matrix (how the 3d model is projected to 2d flat screen, field of view, planes, etc). And distortions matrix is used for example, for warping parts of your input frame in case of detecting something. In the example with watches, we need to detect the belt and watches body in order to place the 3d model in that position. Given the paper watches is not having ideal perspective with 90 degrees angle to the eye, it needs to be transformed to this view.
In other words, your paper watches looks like this:
/---/
/ /
/---/
And for the analysis and detecting the model name you need it look like this:
---
| |
| |
---
This is where distortion matrix is used in order to have precise transformation. And different cameras have their own distortions.
Most of application use so called offline calibration. There is a chessboard and its feed into opencv functions that detect cells on series of frames with different perspective, and build the matrices based on how the cells are shaped.
In your case, the belt of your watch may be designed in a way that it will contain all the needed for online calibration. On your video it has special pattern, I'm pretty sure its done exactly for this purpose. You may do the same and use chessboard pattern for simplicity.
Then you could use lets say 25 first frames for online calibration and then having all the matrixes you go for detecting paper watches, building projection matrix and replace it with your 3d model. If all is done right then your paper watcthes will have coord 0 0 0 in 3d space and you could easily place something else in that position.
I saw that someone has made an app that tracks your feet using the camera, so that you can kick a virtual football on your iPhone screen.
How could you do something like this? Does anyone know of any code examples or other information about using the iPhone camera for detecting objects and tracking them?
I just gave a talk at SecondConf where I demonstrated the use of the iPhone's camera to track a colored object using OpenGL ES 2.0 shaders. The post accompanying that talk, including my slides and sample code for all demos can be found here.
The sample application I wrote, whose code can be downloaded from here, is based on an example produced by Apple for demonstrating Core Image at WWDC 2007. That example is described in Chapter 27 of the GPU Gems 3 book.
The basic idea is that you can use custom GLSL shaders to process images from the iPhone camera in realtime, determining which pixels match a target color within a given threshold. Those pixels then have their normalized X,Y coordinates embedded in their red and green color components, while all other pixels are marked as black. The color of the whole frame is then averaged to obtain the centroid of the colored object, which you can track as it moves across the view of the camera.
While this doesn't address the case of tracking a more complex object like a foot, shaders like this should be able to be written that could pick out such a moving object.
As an update to the above, in the two years since I wrote this I've now developed an open source framework that encapsulates OpenGL ES 2.0 shader processing of images and video. One of the recent additions to that is a GPUImageMotionDetector class that processes a scene and detects any kind of motion within it. It will give you back the centroid and intensity of the overall motion it detects as part of a simple callback block. Using this framework to do this should be a lot easier than rolling your own solution.
I am trying to write a strategy game using XNA 4.0, with a dynamically generating map, and it's really difficult to create all the ground textures, having to distort them individually in photoshop.
So what I want to do is create a flat image, and then apply the distortion programatically to simulate perspective, by moving the corners of the image.
Here is an example done in photoshop:
How can I do that in XNA?
My answer isn't XNA-specific as I've never actually used the library; however the concept should still apply.
In general, the best way to get a good perspective effect is to actually give 3d coordinates and transformations and let DirectX/OpenGL handle the rest. This has great benefits over attempting to do it yourself - specifically, ease of use, performance (much of the work is passed on to your graphics card), and perspective-correct texturing. And nothing's stopping you from doing 3d and 2d in the same scene, if that's a concern. There are numerous tutorials online for getting set up in the third dimension with XNA. I'd suggest heading over to MSDN.