Load Trained SVM – Emgu CV

Question

I am somewhat new to SVMs and object recognition, and am currently attempting to train an SVM using Emgu CV 3.0, save it to a file, and then load it (for use in HOGDescriptor.SetSVMDetector).

However, among other problems, I cannot find a way to load the SVM after I have saved it.

So far, my code basically does the following:

SVM myFirstSVM = new SVM();

// do some stuff, set some parameters...

myFirstSVM.Train(someParameters);

myFirstSVM.Save("filePath");

From here, the problem lies with reloading the SVM after being saved. I have checked several help topics and pages, and the only related things I could find pertained to OpenCV, which used the following method:

SVM mySecondSVM;

mySecondSVM.load("filePath");

However, I could find no method ".load()" in Emgu 3.0, although it appeared to be present in previous versions. Is there an equivalent of this OpenCV method in Emgu 3.0? I would assume there is, and I am sure it is fairly simple, but I cannot for the life of me find it.

score 2 · Answer 1 · edited Jul 22 '16 at 14:15

For EmguCV 3.0.0, the Save/Load functionality doesn't seem to be supported (Load doesn't exist), you could use Write/Read instead.

A function to save an SVM model:

public static void SaveSVMToFile(SVM model, String path) {
    if (File.Exists(path)) File.Delete(path);
    FileStorage fs = new FileStorage(path, FileStorage.Mode.Write);
    model.Write(fs);
    fs.ReleaseAndGetString();
}

A function to load the SVM model provided the correct path:

public static SVM LoadSVMFromFile(String path) {
    SVM svm = new SVM();
    FileStorage fs = new FileStorage(path, FileStorage.Mode.Read);
    svm.Read(fs.GetRoot());
    fs.ReleaseAndGetString();
    return svm;
}

score 1 · Answer 2 · answered Apr 04 '16 at 02:09

I have saved and read the SVM model using the specified functions. But I am working with 3.1.0 version and hope it works for you as well:

I have saved the model in an XML file because the read function works on xml file as far as I know:

Emgu.CV.ML.SVM model = new Emgu.CV.ML.SVM();
model.SetKernel(Emgu.CV.ML.SVM.SvmKernelType.Linear);
model.Type = Emgu.CV.ML.SVM.SvmType.CSvc;
model.C = 1;
model.TermCriteria = new MCvTermCriteria(100, 0.00001);
bool trained = model.TrainAuto(my_trainData, 5);
model.Save("SVM_Model.xml");

and I read the model as follows:

Emgu.CV.ML.SVM model_loaded = new Emgu.CV.ML.SVM();
FileStorage fsr = new FileStorage("SVM_Model.xml", FileStorage.Mode.Read);
model_loaded.Read(fsr.GetFirstTopLevelNode());

and it works correctly. I hope it works for you so.

Berriel · Answer 3 · 2016-03-02T01:39:47.510

0

For EmguCV 1.5.0:

Load Method (fileName):

Inherited from StatModel

Load the statistic model from file

fileName (String)

The file to load the model from

For EmguCV 3.0+:

Load() is not available, as you can see in the source code: https://sourceforge.net/p/emgucv/code/ci/master/tree/Emgu.CV.ML/StatModel.cs

edited Mar 02 '16 at 01:39

answered Mar 01 '16 at 22:28

Berriel

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I did. There is no extension method ".Load("file path")" in Emgu for SVM objects. – Johiasburg Frowell Mar 01 '16 at 23:10
@JohiasburgFrowell Are you sure? This information comes from its documentation: http://www.emgu.com/wiki/files/1.5.0.0/Help/html/5c8147fa-4959-df3f-4d73-f1c549c06738.htm – Berriel Mar 01 '16 at 23:18
I am using version 3.0, the documentation you referenced is severely outdated. 3.0 documentation can be found at http://www.emgu.com/wiki/files/3.0.0/document/html/5c8147fa-4959-df3f-4d73-f1c549c06738.htm – Johiasburg Frowell Mar 01 '16 at 23:34
@JohiasburgFrowell that's interesting... on source code the `Load()` method was commented... perhaps a bug? – Berriel Mar 02 '16 at 01:24

Load Trained SVM – Emgu CV

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