What's the difference between INuiFusionColorReconstruction::IntegrateFrame and ProcessFrame? - kinect

I'm learning KinectFusion, hope to use it to build a reconstruction application for 3D print.
Currently i'm confused by IntegrateFrame and ProcessFrame method of INuiFusionColorReconstruction.
ProcessFrame has one more parameter named maxAlignIterationCount, does it mean that ProcessFrame will do integrate for multiple times while IntegrateFrame only do integrate one time? Since ProcessFrame also only take one reference frame, what's the benefit to do integrate for multiple times?

From Microsoft's website:
"...the ProcessFrame function in the INuiFusionReconstruction interface... encapsulates the camera tracking (AlignDepthFloatToReconstruction) and the data integration step (IntegrateFrame) in one function call to be easier to call and more efficient as all processing takes place on the GPU without upload and readback for the individual steps as would occur when calling separately."
Kinect for Windows 1.7, 1.8

Related

How can I use functions in another program

I want to create a simulation program, for BUS related simulations.
These simulations use lot of calculations, and methods, and there are more and more.
First I want to write the Core of the program, which can use separately coded and compiled program blocks. What kind of programming technology is good for this?
For example: I want to send a CAN frame with checksum calculation. In the core program I choose from a directory that which checksum calculation is good for me.

CNTK: Python vs C# API for model consumption

We have trained a model using CNTK. We are building a service that is going to load this model and respond to requests to classify sentences. What is the best API to use regarding performance? We would prefer to build a C# service as in https://github.com/Microsoft/CNTK/tree/master/Examples/Evaluation/CSEvalClient but alternatively we are considering building a Python service that is going to load the model in python.
Do you have any recommendations towards one or the other approach? (regarding which API is faster, actively maintained or other parameters you can think of). The next step would be to set up an experiment measuring the performance of both API calls, but was wondering if there is some prior knowledge here that could help us decide.
Thank you
Both APIs are well developed/maintained. For text data I would go with the C# API.
In C# the main focus is fast and easy evaluation and for text loading the data is straightforward.
The Python API is good for development/training of models and at this time not much attention has been paid to evaluation. Furthermore, because of the wealth of packages loading data in exotic formats is easier in Python than C#.
The new C# Eval API based on CNTKLibrary will be available very soon (the first beta is probably next week). This API has functional parity with the C++ and Python API regarding evaluation.
This API supports using multiple threads to serve multiple evaluation requests in parallel, and even better, model parameters of the same loaded model is shared between these threads, which will significantly reduce memory usage in a service environment.
We have also a turorial about how to use Eval API in ASP.Net environment. It still refers to EvalDLL evaluation, but applies to the new C# API too. The document will be updated after the new C# API is released.

Back&: Compute Units

I'm working with the Backand with an Ionic mobile app that I'm developing. It's a data intensive app so I'm wanting to make sure doing my interactions most efficiently. Is there some parameters documented somewhere that tells me what are better ways to make calls? Like I'm assuming a Query using MySQL does requires more Compute Units than a REST GET call with filter but how much less? Thanks for any help as I haven't found any documentation on Backand Compute Units.

is it possible to track an arbitrary skeleton model with the kinect?

I understand that the kinect is using some predefined skeleton model to return the skeleton based on the depth data. That's nice, but this will only allow you the get a skeleton for people. Is it possible to define a custom skeleton model? for example, maybe you want to track your dog while he's doing something. So, is there a way to define a model for four legs, a tail and a head and to track this?
Short answer, no. Using the Microsoft Kinect for Windows SDK's skeleton tracker you are stuck with the one they give you. There is no way inject a new set of logic or rules.
Long answer, sure. You are not able to use the pre-built skeleton tracker, but you can write your own. The skeleton tracker uses data from the depth to determine where a person's joints are. You could take that same data and process it for a different skeleton structure.
Microsoft does not provide access to all the internal functions that process and output the human skeleton, so we would be unable to use it as any type of reference for how the skeleton is built.
In order to track anything but a human skeleton you'd have to rebuild it all from the ground up. It would be a significant amount of work, but it is doable... just not easily.
there is a way to learn a bit about this subject by watching the dll exemple:
Face Tracking
from the sdk exemples :
http://www.microsoft.com/en-us/kinectforwindows/develop/

Does anyone have any idea how to create a 2D skeleton with the Kinect depthmap?

I'm currently using a Processing Kinect library which supplies a depth map. I was wondering how I could take that and use it to create a 2D skeleton, if possible. Not looking for any code here, just a general process I could use to achieve those results.
Also, given that we've seen this in several of the Kinect games so far, would it be difficult to have multiple skeletons running at once?
Disclaimer: the reason why you still didn't get an answer for this question is probably because that's a current research problem. So I can't give you a direct answer but will try to help with some information and useful resources for this topic.
There are mainly 2 different approaches to create a skeleton from a depth map. The first one is to use machine learning, the second is purely algorithmic.
For the machine learning one, you'd need many samples of people doing a predetermined move, and use those samples to train your favorite learning algorithm. That's the approach that was taken and implemented by Microsoft in the XBox (source), it works really well BUT you need millions of samples to make it reliable... quite a drawback.
The "algorithmic" approach (understand without using a training set) can be done in many different ways and is a research problem. It's often based on modeling the possible body postures and trying to match that with the depth image received. That's the approach that was chosen by PrimeSense (the guys behind the kinect depth camera technology) for their skeleton tracking tool NITE.
The OpenKinect community maintains a wiki where they list some interesting research material about this topic. You might also be interested in this thread on the OpenNI mailing list.
If you're looking for an implementation of a skeleton tracking tool, PrimeSense released NITE (closed source), the one they made: it's part of the OpenNI framework. That's what's used in most of the videos you might have seen that involve skeleton tracking. I think it's able to handle up to 2 skeletons at the same time, but that requires confirmation.
The best solution is to use FAAST (http://projects.ict.usc.edu/mxr/faast/) which requires OpenNI. I have struggled to get OpenNI to work on my computer. I have not seen an approach yet using Code Laboratories' CL NUI.
An algorithmic approach is http://code.google.com/p/skeletonization/ but you may have a problem because your depthmap only represents surfaces and no closed objects.