How do you do reconstruction by threshold decomposition in Matlab? Is there a function for it?
Can you provide some more details of the steps in such a procedure? Some of us are not well versed in DSP theory. I did find a link from a book in Google books here.
If this is exactly what you want it does not seem difficult to code it up. On the other hand if you want something reliable and optimized for speed maybe on of the DSP toolkit users knows a way.
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I know that few people use Dymola's commercial library thermal power, but I ask a detailed question with a try attitude. If anyone understands and answers, thank you very much.
Question: how to set the steam side heat transfer coefficient of condenser assembly (divided into three condensation sections) in thermal power to ensure that it will meet different application environments as much as possible. I know this is an empirical value, but I still want to find some basis.
Finally, I just contacted this community (but it doesn't mean I didn't retrieve relevant questions), so I don't ask standardized questions. I hope to get understanding. Thank you.
I want to do hand gesture recognition with hmm in matlab. I studied the theoretical materials in both hmm concept and hmm in mathwork . But I need to see some real examples which uses matlab instructions for dealing with hmm. I searched in the web but could not find a good one. Does any one know a reference which uses matlab instructions in a hmm process?
I suggest you look at the toolbox by K. Murphy and its tutorial.
The built-in hmm functions in Matlab are pretty limited I find (though I did not use the very last edition of Matlab). However you can look at the Matlab tutorial too.
Finally, you can check this toolbox. It contains a demo file.
On a side note, be aware that your question is somewhat off-topic here. Adding some code to show that you a least tried something and clearly spot what is causing you trouble (training the model? formatting the data? applying the Viterbi algorithm?) would make this question much more interesting to the community.
Can someone direct me to a document or some kind of source about the "magic" behind trainCascadeObjectDetector? I was looking around for quite a bit but couldn't find anything. Thank you for your time.
Check the answer on MATLAB Answers:
Hello Dai,
Do you need to explain how the face detector itself works, or how the training of the face detector works?
vision.CascadeObjectDetector implements the deletection algorithm by Viola and Jones. It is a "sliding-window" approach, which slides a window across an image, and tries to determine whether or not there is a face in each location using a cascade of boosted classifiers. The original algorithm uses Haar-like features. vision.CacadeObjectDetector also gives you the option to use LBP or HOG features.
The Algorithms section of the vision.CascadeObjectDetector documentation gives a good high-level overview of what it is doing.
As far as the training process, there is a tutorial in the documentation explaining some of the details.
For my computer vision class, I'm going to be doing a project where I extract information about a hallway based on an image of that hallway. In particular, the lines of the hallway which extend toward a vanishing point will be of interest. My question is whether I should use Matlab, OpenCV, or something else to implement this.
I don't have a ton of time for this project. This fact makes Matlab seem like a good option since it seems you can usually get things up and running quickly there. On the other hand, I hope to take what I do for this class project and extend it out further for research once the class is complete. This makes OpenCV seem better as (from what I've read) it's much more efficient. It's possible another choice would be to implement it in Matlab for the project than port that code to an OpenCV form later. It should be noted that I have plenty of experience with C/C++, but only a little in both Matlab and OpenCV.
At the moment, I'm leaning toward just using OpenCV from the start. However, I would like the opinion of someone who's had a bit more experience here than myself. If you'd recommend something over both OpenCV and Matlab, please say so. Also, if you have any tips on what packages or toolkits might be useful for such a project, they would be greatly appreciated.
Any suggestions? Thanks for your time!
Using which one it is easier for you to write a piece of code to read an image file and display it?
If you know C++ very well, then it should be easy to debug the code. Since you say you have little experience with Matlab, if you make a small mistake in the code debugging can take a long time.
So I suggest break down the problem into:
read image and display it, this is very easy in both
detect edges using a simple/classic method, this is super easy in both, display the result and visually check it's correctly done
use a robust line fitting method, the RANSAC and Hough transform methods are probably what you're going to use, OpenCV makes using the easier than you can guess, Matlab also has built in functions to detect lines using the Hough transform, and gives you the start/end points of each segment. But if you're finding a vanishing point, you shouldn't need those.
The decision is yours, this is not a very difficult problem, can find loads of help on the web. Good luck with the project, and please let us know how it goes.
I m doing a research project on "Object detection using my a digital camera".
Some suggestion on how to build and program the Matlab code.
In particular, I have a picture of one object, say a screen of my laptop. Than I rotate the laptop and I shot a new picture. I would like to know the difference on the position of the screen. I think I can use the edge detection after a subtraction of the two images but... it is quite difficult for me to implement it.
Some suggestion on how to build and program the matlab code.
That largely depends on the goal you want to achieve. Can you be more specific? Are you streaming the frames or are you tracking offline?
In particular, i have a picture of one object, say a screen of my laptop. Than i rotate the laptop and i shot a new picture. I would like to know the difference on the position of the screen.
There are many ways to do this, and an extensive litterature on the subject. I don't believe anyone would write up the equivalent of a survey paper on the subject as an answer on StackOverflow. Why don't you get started with an object tracking survey paper and then ask a more precise question?
hi, I m doing a reasearch project on "Object detection using my a digital camera". [...] I think i can use the edge detection after a subtraction of the two images but...is quite difficult for me to implement it.
What is your question? Are you asking us if this is a good way to track objects? Are you asking us if this is a new approach and has never been done? Are you asking someone to implement it for you?
Object tracking is a hard problem. I doubt that technique would succeed in any but the most basic scenarios. However, if you look at a survey paper, you might be pointed to a paper that already implemented this an presents results. Finally, I think you should brush up your programming skills because most (successful) object tracking techniques are not trivial to implement. If you don't want to program it yourself, there are online services where you can hire people. StackOverflow is not one of those places.
EDIT: I could deduce that you're new to both programming (in MATLAB) and in object tracking, hence in my answer. Don't mis-understand me, I'm trying to help. Let me re-phrase my suggestions as list:
Your question is far too general. You will get a lot more help from the SO community if you ask more precise questions for two reasons: A) general question result in general answers; and B) the way you asked your question could easily be interpreted as "someone, please do my work for me" even if that's not what you think you're asking.
Get acquainted with the problem domain. To ask more precise questions, you must be close to your answer. For good knowledge on the "object detection and tracking", find a good survey paper. If you're starting off on a research project, people in your lab should be of help to point you to a good one.
Learn to program simple things first. All of the most proficient (effective and efficient) programmers I've ever met struggled with the bubble sort when they were introduced to sorting. None of them would have been able to program an object detection algorithm as a first assignment. Get yourself a good image processing book that has exercises in MATLAB, go through execises one by one. If you can't do them all, choose those that are relevant to what you're trying to accomplish.