Im trying to perform centerline extraction for cardiac CT images, and I am stuck. I need an example code that uses the "fast marching method". I got this code from mathworks.
I1=im2double(imread('se036.png'));
SpeedImage=I1*1000+0.001;
SourcePoint=[800;803];
DistanceMap= msfm(SpeedImage, SourcePoint);
figure
imshow(DistanceMap,[0 3400]) StartPoint=[9;14];
ShortestLine=shortestpath(DistanceMap,StartPoint,SourcePoint);
hold on
plot(ShortestLine(:,2),ShortestLine(:,1),'r')
But I get error message Undefined function 'msfm' for input arguments of type 'double'.
It appears you are trying to use the Matlab File Exchange submission Accurate Fast Marching but you haven't properly installed the code. The function file you downloaded, msfm.m, needs to be in a folder on your path or in the current working directory.
Related
i'm trying to use getpts to choose points in the current figure using the mouse. However, when i run it, i'm getting the error "unrecognized function or variable 'getpts'."
Here's my code
for i=1:n
im = imread([read_path 'IMG_' num2str(i+t) '.jpg']); %Get image
figure
imshow(im)
[x,y] = getpts; %returns error
end
Any idea why that's happening?
Note: I'm using the free trial version of Matlab
I'd appreciate the help!
From the docs, getpts is in the image processing toolbox.
This isn't always obvious, you can infer it from the docs link itself:
mathworks.com/help/images/ref/getpts.html
(where a built-in would be something like mathworks.com/help/matlab/ref/sum.html)
You can also see it's nested under the image processing toolbox in the side-bar on that page.
In your trial installation of MATLAB you likely don't have this toolbox. You might know from the install process, or you could check whether the toolbox folder exists in the installation directory, e.g.
I have an m file from which I use to create dll using the Matlab deploytool. the code simply reads as:
function hello
disp('Hello')
end
there are six functions in the compiled dll exported as:
uint8 helloInitialize
[uint8, voidPtr, voidPtr] helloInitializeWithHandlers(voidPtr, voidPtr)
helloPrintStackTrace
helloTerminate
uint8 mlfHello
[uint8, MATLAB arrayPtr, MATLAB arrayPtr] mlxHello(int32, MATLAB arrayPtr, int32, MATLAB arrayPtr)
Now I want to run this dll from my matlab command window using calllib and use
the hello function. Assuming that I use the correct function mlfHello, calllib('hello','mlfHello') gives me nothing. Please advise me on what function to call and how to do it?
I'm not 100% its still the case but it certainly used to be that you couldn't load DLL's which were created in Matlab back into Matlab.
I suspect its still the case - so you cant do what your trying to do.
[edit] I dont have a link because they dont like to advertise the fact. The reason AFAIK is to avoid users compiling toolbox capability into DLL and giving to others to use in Matlab without a toolbox license.
I want to use fig2texPS to export plots from MATLAB to LaTeX. I copied the the script to D:\Eigene Dokumente\MATLAB\fig2TexPS and added this folder as a path in MATLAB. Unfortunately, I receive the following error:
>> fig2texPS()
Undefined function 'find' for input arguments of type 'matlab.graphics.chart.primitive.Line'.
Error in fig2texPS (line 526)
lsh = double(find(handle(lshandles),'-class','graph2d.lineseries')); % find plots
PS: I use a version of the script which was updated in order to work with pdtlatex (http://pastebin.com/xK6KxxBT) that I found in the MATLAB Central File Exchange. The same error also occurs when I use the original script.
This might not be the answer you are looking for, but there is the marvelous matlab2tikz that does the job of conversion of figures quite nicely, which you could use as an alternative to fig2texPS.
I also use the function fig2texPS.m and it works very well. It might be an answer for your question to use an older version of Matlab. I am using 2013b and it works. While I have tried this function with Matlab 2015a, I was getting the same error message.
I hope my answer helps you with your problems.
I want to know how can this function(from MATLAB) resize the columns of an input image using weights an indices previously computed.
Which equations uses to do that?
resizeColumnsCore(double(in), weights', indices');
When I looked for a function called resizeColumnsCore in MATLAB 7.11.0 (R2010b) I didn't find anything. However, I did find a MEX-file by that name in MATLAB 7.8.0 (R2009a) in this subdirectory of the Image Processing Toolbox:
C:\Program Files\MATLAB\R2009a\toolbox\images\images\private\
I guess they've phased it out or replaced it with another function in newer MATLAB versions. Now, if you want to know what the MEX-file does, you need to look at the source code it is compiled from. Luckily, it appears that this source code resizeColumnsCore.cpp can be found in the following directory:
C:\Program Files\MATLAB\R2009a\toolbox\images\images\private\src\misc\
And you can look through that code to determine the algorithms used to resize the columns of an image given a set of weights and indices.
Now, if you want to know how these input arguments to resizeColumnsCore are computed, you'll have to look at the code of a function that calls it. I know of at least one function in the IPT that calls this function: IMRESIZE. If you type edit imresize at the command prompt it will open that function in the Editor, allowing you to look through the code so you can see how the arguments to resizeColumnsCore are created.
What I can tell you for R2009a is that there is a subfunction in the file imresize.m called contributions which computes the weights and indices that are ultimately passed as arguments to resizeColumnsCore. That is where you will want to start looking to determine what algorithms are used to compute these arguments.
Looks like this isn't a proprietary MATLAB function. Could we see some code or a link to the code?
This function bwmorph(Img,'skel',Inf) return the skeleton of a binary image.
What I'm looking for is the algorithm used by this function to do it manualy ?
The documentation gives an overview of the algorithm (scroll down a ways).
If you want to see the actual code within a function in MATLAB, you can try using the TYPE command:
type bwmorph %# Command form
type('bwmorph.m') %# Function form
Keep in mind, this will not work on all MATLAB functions. You may get a message that says the function is a built-in function, in which case the code will not be displayed. You can also try opening the file in the MATLAB Editor using the EDIT command:
edit bwmorph.m %# Command form
edit('bwmorph.m') %# Function form