How to Volume Render from a Stack of 2D Slices and (Possibly?) Generate a Mesh?

Questions & Answers
1

I am looking to render a volume using a stack of 2D images, such as MRI data, and possibly generate a mesh from that data. Methods I have looked into for volume rendering with Ray Marching typically result in a volume not calculated in world space. I would need the object to render in World Space with other meshes woven in the semi-transparent volume, meaning setting a static render layer would not solve this to my knowledge.

Would it be possible to analyze the 2D image stack and create a mesh / detailed voxel mesh from the RGBA data, given the layer spacing?

Any information on techniques that would guide me towards an answer such as in-depth how-to for ray-marching for world-space rendering in Unity or efficient 3D mesh rendering from 2D image stacks would be greatly appreciated (the mesh generation does not need to be done at run-time on a build but the mesh would need to be saved out).

I apologize for ignorance on the details of the methods used to accomplish what I want to do and the terminology in advance but I am trying to explain in depth what I am trying to accomplish.

Thank you!

2

Im working on something similar, i am coding point clouds from stacks of images to process them in a point cloud program or meshlab. edge detection depends on the image you start from, if it is BW or color, you have to decide what criteria you want.

then march along the top and bottom image, get all the pixels that represent an volume, then march through all the other layers and race through the edges and check out what pixels you want from there inthe point cloud/mesh and then march through the images themselves detecting every color which changes from B/W as a border or which is a certain shade as a threshold where vertices can be.

i’ve finished a code in BW, it’s about 5 7 hours work i can send it along for 10 dollars i have my bank nagging me. regards.

3

@Izaaner If it does not need to be done at run-time I would suggest freeware such as 3DSlicer (https://www.slicer.org/)
which lets you do everything you’ve mentioned and save to an OBJ or STL file. If it needs to be done at run-time in Unity I’m still searching for an answer to this.