What is the equivalent of "getDecisionFunction" from OpenCV in C# "EmguCV"?

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What is the equivalent of "getDecisionFunction" from OpenCV in C# "EmguCV"?
C# EmguCV/OpenCV "cvThreshold" abnormal behaviour - no expected threshold result
{"error":{"message":"Services require JSON-RPC","code":0,"origin":2},&
C# EmguCV error "OpenCV: u != 0"
What's the javascript equivalent of $("<option>", { value: "thing1", text: "thing2"
Laravel: [ErrorException] "continue" targeting switch is equivalent to "break". during "compose

What is the equivalent of "getDecisionFunction" from OpenCV in C# "EmguCV"?

Tag : chash , By : Marcos de Carvalho

Date : November 26 2020, 03:04 PM

I hope this helps you . I think there is no explicit function for getDecisionFunction in EmguCV. I didn't even find a direct way to get the required values of rho, alpha and svidx. The only solution I found - thanks to @deon cagadoes - is to rewrite the function using the open source of OpenCV OpenCV SVM. However, I wasn't able to acquire all data directly, so I had to write the values of SVM to a file then getting all what I need from this file.

private void TrainandLoad()
{   
    double rho;
    Mat sv, alpha, svidx;
    SVM svm;
    svm.Train(train_data, Emgu.CV.ML.MlEnum.DataLayoutType.RowSample, labels);
    svm.Save(TRAINED_SVM);
    sv = svm.GetSupportVectors();
    alpha = new Mat();
    svidx = new Mat();
    rho = GetDecisionFunction(0, alpha, svidx);
}

private double GetDecisionFunction(int i, IOutputArray alpha, IOutputArray svidx)
{
    int j, nl, idf, class_count, sv_total, df_size, df_index_size, count;
    string svmType, rem;
    Mat tmp;
    DecisionFunc df;
    int[] sv_count;
    string[] lines;
    DecisionFunc[] dfs;
    int[][] svind;
    double[][] alph;
    lines = File.ReadAllLines(TRAINED_SVM);
    nl = 0;
    svmType = "";
    while (nl < lines.Length)
    {
        if (lines[nl].IndexOf("svmType") != -1)
        {
            svmType = lines[nl].Substring(lines[nl].IndexOf("svmType") + 9);
            nl++;
            break;
        }
        nl++;
    }
    if (svmType == "C_SVC" || svmType == "NU_SVC")
    {
        class_count = 2;
        while (nl < lines.Length)
        {
            if (lines[nl].IndexOf("class_count") != -1)
            {
                class_count = Convert.ToInt32(lines[nl].Substring(lines[nl].IndexOf("class_count") + 13));
                nl++;
                break;
            }
            nl++;
        }
        df_size = class_count * (class_count - 1) / 2;
    }
    else
    {
        if (svmType == "ONE_CLASS")
            class_count = 1;
        else
            class_count = 0;
        df_size = 1;
    }
    sv_total = 1;
    while (nl < lines.Length)
    {
        if (lines[nl].IndexOf("sv_total") != -1)
        {
            sv_total = Convert.ToInt32(lines[nl].Substring(lines[nl].IndexOf("sv_total") + 10));
            nl++;
            break;
        }
        nl++;
    }
    Debug.Assert(i <= 0 && i < df_size);
    while (nl < lines.Length)
    {
        if (lines[nl].IndexOf("decision_functions") != -1)
        {
            nl++;
            break;
        }
        nl++;
    }
    sv_count = new int[df_size];
    dfs = new DecisionFunc[df_size];
    svind = new int[df_size][];
    alph = new double[df_size][];
    idf = dfs[0].ofs = df_index_size = 0;
    while (nl < lines.Length && idf < df_size)
    {
        if (lines[nl].IndexOf("sv_count") != -1)
            sv_count[idf] = Convert.ToInt32(lines[nl].Substring(lines[nl].IndexOf("sv_count") + 10));
        else if (lines[nl].IndexOf("rho") != -1)
            dfs[idf].rho = Convert.ToDouble(lines[nl].Substring(lines[nl].IndexOf("rho") + 5));
        else if (lines[nl].IndexOf("alpha") != -1)
        {
            alph[idf] = new double[sv_count[idf]];
            rem = lines[nl].Substring(lines[nl].IndexOf("alpha") + 9);
            for (j = 0; j < sv_count[idf]; j++)
            {
                while (rem[0] == ' ')
                    rem = rem.Substring(1);
                alph[idf][j] = Convert.ToDouble(rem.Substring(0, rem.IndexOf(' ')));
                rem = rem.Substring(rem.IndexOf(' '));
            }
            if (idf != 0)
                dfs[idf].ofs = dfs[idf - 1].ofs + sv_count[idf];
            df_index_size += sv_count[idf];
            if (class_count < 2)
                idf++;
        }
        else if (lines[nl].IndexOf("index") != -1)
        {
            svind[idf] = new int[sv_count[idf]];
            rem = lines[nl].Substring(lines[nl].IndexOf("index") + 9);
            for (j = 0; j < sv_count[idf]; j++)
            {
                while (rem[0] == ' ')
                    rem = rem.Substring(1);
                svind[idf][j] = Convert.ToInt32(rem.Substring(0, rem.IndexOf(' ')));
                rem = rem.Substring(rem.IndexOf(' '));
            }
            idf++;
        }
        nl++;
    }
    df = dfs[i];
    //Get SV Count
    count = (i < df_size - 1 ? dfs[i + 1].ofs : df_index_size) - dfs[i].ofs;
    if (class_count < 2)
    {
        svind[0] = new int[sv_total];
        for (j = 0; j < sv_total; j++)
            svind[0][j] = j;
    }
    tmp = new Mat(1, count, DepthType.Cv64F, 1);
    tmp.SetTo<double>(alph[i]);
    tmp.CopyTo(alpha);
    tmp.Dispose();
    tmp = new Mat(1, count, DepthType.Cv32S, 1);
    tmp.SetTo<int>(svind[i]);
    tmp.CopyTo(svidx);
    tmp.Dispose();
    return df.rho;
}

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What is the equivalent of "getDecisionFunction" from OpenCV in C# "EmguCV" , C# EmguCV/OpenCV "cvThreshold" abnormal behaviour - no expected threshold result , Whats the javascript equivalent of $("<option>" , { value: "thing1" , text: "thing2&q ,

C# EmguCV/OpenCV "cvThreshold" abnormal behaviour - no expected threshold result

Tag : chash , By : brij

Date : March 29 2020, 07:55 AM

To fix this issue The reason of an appearing of that gray artifacts on saved images after applying of any kind of a threshold is... *.JPG standard saving format of Image! More precisely, a jpeg compression applied by it. So there was no problem with thresholding itself. Just a spoiled output image. It was confusing strongly though. The right way of saving such images (without artifacts) is, for example: Image.Bitmap.Save(your_path, ImageFormat.Bmp)

{"error":{"message":"Services require JSON-RPC","code":0,"origin":2},&

Tag : javascript , By : FuzzyHornet

Date : March 29 2020, 07:55 AM

wish of those help JSON RPC expects the client to send parameters to the server using an HTTP POST command with the procedure parameters in the post data. When you type a URL into the browser it sends an HTTP GET command, which doesn't send any parameters.
RPC is intended for use by application programs, not directly by end users. See http://json-rpc.org/ for more details about it.

C# EmguCV error "OpenCV: u != 0"

Tag : chash , By : Saurabh

Date : March 29 2020, 07:55 AM

To fix the issue you can do That exception seems to indicate that app is taking too much memory. In my case I just seemed to have too good quality for the pictures. Reducing them to half fixed the problem.

What's the javascript equivalent of $("<option>", { value: "thing1", text: "thing2"

Tag : javascript , By : Randoa

Date : March 29 2020, 07:55 AM

will be helpful for those in need Using JavaScript we can create a helper function that assists us in replicating the functionality of the JQuery method.

let create = (tag, opts = {}) => {
  return Object.assign(document.createElement(tag), opts); 
}

let create = (tag, opts = {}) => {
  return Object.assign(document.createElement(tag), opts); 
}

console.log( 
  create("option", { value: "thing1", textContent: "thing2"})  
);

Laravel: [ErrorException] "continue" targeting switch is equivalent to "break". during "compose

Tag : laravel , By : Bin

Date : October 05 2020, 04:00 PM

fixed the issue. Will look into that further This is a new warning introduced in PHP 7.3.
It means you are not allowed to have a continue statement inside of a switch, you should use break instead.