sp_mic88's profile - activity

I'm developing an Android application, using OpenCV4Android ver. 2.4.9. The application opens, using JavaCameraView, a video-stream and allows to apply various effects to this stream.

For example, I have created this Vignette Filter:

public static void getVignetteFilters(Mat frame){
    int num_rows = frame.rows();
    int num_cols = frame.cols();
    Mat first_filter = Imgproc.getGaussianKernel(num_cols, 300);
    Mat second_filter = Imgproc.getGaussianKernel(num_rows, 300);
    Mat first_filter_transposed = first_filter.t();
    Log.i(TAG, "First Filter Transposed: Rows = " + first_filter_transposed.rows() + " Cols = " + first_filter_transposed.cols());
    Log.i(TAG, "Second Filter: Rows = "+second_filter.rows()+" Cols = "+second_filter.cols());
    Mat third_filter = new Mat();
    Core.multiply(second_filter, first_filter_transposed, third_filter);
    Core.MinMaxLocResult minMaxLocResult = Core.minMaxLoc(third_filter);
    double maxVal = minMaxLocResult.maxVal;
    Mat fourth_filter = new Mat();
    Core.divide(maxVal, third_filter, fourth_filter);
    Core.multiply(frame, fourth_filter, frame);
}

But when I try to apply it to my stream, this operation fails, due to this exception:

CvException [org.opencv.core.CvException: cv::Exception: /home/reports/ci/slave_desktop/50-SDK/opencv/modules/core/src/arithm.cpp:1287: error: (-209) The operation is neither 'array op array' (where arrays have the same size and the same number of channels), nor 'array op scalar', nor 'scalar op array' in function void cv::arithm_op(cv::InputArray, cv::InputArray, cv::OutputArray, cv::InputArray, int, void (**)(const uchar*, size_t, const uchar*, size_t, uchar*, size_t, cv::Size, void*), bool, void*)
]
        at org.opencv.core.Core.multiply_2(Native Method)
        at org.opencv.core.Core.multiply(Core.java:5229)

But in the logcat I have verified that the two matrices that I pass to the Core.multiply method have the number of columns of the first equal to the number of rows of the second, so the multiplication should be possible between them.

11-04 20:55:43.444  21376-21603/[...]::OpenCVFilters﹕ First Filter Transposed: Rows = 1 Cols = 1920
11-04 20:55:43.444  21376-21603/[...]::OpenCVFilters﹕ Second Filter: Rows = 1080 Cols = 1

Any help would be appreciated.

The problem doesn't change. Now, I'll try to create the network in a new project. Anyway, thanks for all this help!

Ok, the number of iterations is: 2 and the predicted value is: -1.17204 with exactly the parameter's values of the code above (it should be wrong because I should have values in the range [-1,1]). The classes of training are -1 and 1 and the layers of the net are two, one of 59 inputs and one of 1 output.

I tried to change the entire set of training images on which I have calculated the feature vector. I also changed the network so that it is formed of only two levels (input / output). Even in this case the network does not predict, returns the same value for each feature vector of test.

Yes, but it gives me the same results for every sample.

I have created a neural network with CvANN_MLP class, working with Opencv libraries in the 2.4.6 version. My Cv_ANN mlp network is:

 Mat trainingData(NUMERO_ESEMPI_TOTALE, 59, CV_32FC1);  
Mat trainingClasses(NUMERO_ESEMPI_TOTALE, 1, CV_32FC1);

for(int i=0;i<NUMERO_ESEMPI_TOTALE;i++){
    for(int j=0;j<59;j++){
        trainingData.at<float>(i,j) = featureVect[i][j];
    }
}

for(int i=0;i<NUMERO_ESEMPI_TOTALE;i++){
    trainingClasses.at<float>(i,0) = featureVect[i][59];
}

Mat testData (NUMERO_ESEMPI_TEST , 59, CV_32FC1);
Mat testClasses (NUMERO_ESEMPI_TEST , 1, CV_32FC1);
for(int i=0;i<NUMERO_ESEMPI_TEST;i++){
    for(int j=0;j<59;j++){
        testData.at<float>(i,j) = featureVectTest[i][j];
    }
}

//0 bocca, 1 non bocca.
testClasses.at<float>(0,0) = 1;
testClasses.at<float>(1,0) = 0;
testClasses.at<float>(2,0) = 1;
testClasses.at<float>(3,0) = 1;
testClasses.at<float>(4,0) = 0;
testClasses.at<float>(5,0) = 1;
testClasses.at<float>(6,0) = 0;
testClasses.at<float>(7,0) = 1;
testClasses.at<float>(8,0) = 1;
testClasses.at<float>(9,0) = 0;
testClasses.at<float>(10,0) = 0;
testClasses.at<float>(11,0) = 1;
testClasses.at<float>(12,0) = 0;
testClasses.at<float>(13,0) = 0;
testClasses.at<float>(14,0) = 0;
testClasses.at<float>(15,0) = 0;
testClasses.at<float>(16,0) = 0;
testClasses.at<float>(17,0) = 0;
testClasses.at<float>(18,0) = 0;
testClasses.at<float>(19,0) = 1;
testClasses.at<float>(20,0) = 1;
testClasses.at<float>(21,0) = 0;
testClasses.at<float>(22,0) = 1;
testClasses.at<float>(23,0) = 0;
testClasses.at<float>(24,0) = 1;
testClasses.at<float>(25,0) = 0;
testClasses.at<float>(26,0) = 0;
testClasses.at<float>(27,0) = 1;
testClasses.at<float>(28,0) = 1;
testClasses.at<float>(29,0) = 1;    

Mat layers = Mat(3, 1, CV_32SC1);
layers.row(0) = Scalar(59);
layers.row(1) = Scalar(3);
layers.row(2) = Scalar(1);

CvANN_MLP mlp;
CvANN_MLP_TrainParams params;
CvTermCriteria criteria;
criteria.max_iter = 100;
criteria.epsilon = 0.0000001;
criteria.type = CV_TERMCRIT_ITER | CV_TERMCRIT_EPS;
params.train_method = CvANN_MLP_TrainParams :: BACKPROP;
params.bp_dw_scale = 0.05 ;
params.bp_moment_scale = 0.05 ;
params.term_crit = criteria ;
mlp.create(layers);
// train
mlp.train(trainingData,trainingClasses,Mat(),Mat(),params);

Mat response(1, 1, CV_32FC1);
Mat predicted(testClasses.rows, 1, CV_32F);
Mat pred(NUMERO_ESEMPI_TEST, 1, CV_32FC1);
Mat pred1(NUMERO_ESEMPI_TEST, 1, CV_32FC1);
for(int i = 0; i < testData . rows ; i++){
    Mat response(1, 1, CV_32FC1);
    Mat sample = testData.row(i);
    mlp.predict(sample,response);
    predicted.at<float>(i ,0) = response.at <float>(0,0);
    pred.at<float>(i,0)=predicted.at<float>(i ,0);
    pred1.at<float>(i,0)=predicted.at<float>(i ,0);
    file<<"Value Image "<<i<<": "<<predicted.at<float>(i ,0)<<"\n";
    //cout<<"Value Image "<<i<<": "<<predicted.at<float>(i ,0)<<endl;
}

The problem is that this network return me for every test sample the same result. I don't know why. My network takes as input a set of feature vector with 59 input values and 1 output value. Could you help me?

Thanks in advance.

Yes, it has to be predout.data.fl[0]. But now, all the values are equal. Why? What's wrong in the code?

How can I write my c++ JNI function so that it returns an array of Mat to Java code? I am programming in Android environment, with the help of NDK to use also some functions of OpenCV.

My c++ function is:

 JNIEXPORT void JNICALL Java_com_micaela_myapp_MainActivity2_getFrames(JNIEnv* env, jobject object, jstring path)
{
    const char *str;
    str = env->GetStringUTFChars(path, NULL);   
    VideoCapture input_video;
    if(input_video.open(str)){
        cout<<"Video File Opened"<<endl;
    }else{
        cout<<"Video File Not Found"<<endl;
    }
    Mat image;
    Mat frameBuffer[1000];  
    int i=0;
    while(input_video.read(image)==true){
        image.copyTo(frameBuffer[i]);
        i++;
    }
}

In Java I have:

static{
    System.loadLibrary("myapp");
}
public static native void getFrames(String path);

This function now returns void and works properly. However, my purpose is to obtain the array frameBuffer from it, in order to use it in Java. How can I do this?

I've followed exactly that guide to install opencv on vs 2012. So I'll try to install the new version of the libraries.

Do the opencv libraries contain functions to subject a grayscale image to an L-level discrete wavelet decomposition? I want to calculate the three detail images HL, LH and HH for every level, in order to use them to obtain the weighted standard deviation decriptor (WSD).

I have already identified the face, and within it the regions of eyes, nose and mouth. For this purpose, I have used cascade classifiers of opencv. The problem is that the mouth classifier returns a lot of false positive. So, my purpose was to find a way to analyze the ROI of mouth, to check if it really contains a mouth. So, for example, I can think to study the color of image, because red pixel are probably pixel of mouth. I can also study the texture of mouth.

So do you suggest me to use another classifier? Because I have already trained one, and this returns me that set of roi. My goal was to study these without other classifiers, but analysing with the help of texture or color information (it's only an idea).

I have a question to ask: suppose you have a classifier that locate the mouth within the face in an image, this classifier returns multiple ROI as a result. I would like to do further analysis on each of these roi, to determine if, within these, there really is a mouth or not. How could I make this kind of analysis? What are the techniques of image processing to use? I would be grateful if you could recommend some article, or link me the material that may still be useful to me.

Yes, I've used the flip method, in this way: if (rot == 270) { // Rotate clockwise 270 degrees Core.flip(mat.t(), mat, 0); } else if (rot == 180) { // Rotate clockwise 180 degrees Core.flip(mat, mat, -1); } else if (rot == 90) { // Rotate clockwise 90 degrees Core.flip(mat.t(), mat, 1); } See here for more details: http://www.technolabsz.com/2012/08/how-to-flip-image-in-opencv.html

I am developing an Android application, using Opencv libraries (version 2.4.5). The application simply opens a video stream and captures frames from it. Every frame is processed with image-processing techniques in order to detect faces and, within them, features (fiducial points).

I use, for eyes, the matchTemplate method, and sometimes, I have this error:

 07-30 11:26:44.355: ERROR/AndroidRuntime(23441): FATAL EXCEPTION: Thread-10570
    CvException [org.opencv.core.CvException: /home/reports/ci/slave_desktop/50-SDK/opencv/modules/imgproc/src/templmatch.cpp:70: error: (-215) corrsize.height <= img.rows + templ.rows - 1 && corrsize.width <= img.cols + templ.cols - 1 in function void cv::crossCorr(const cv::Mat&, const cv::Mat&, cv::Mat&, cv::Size, int, cv::Point, double, int)
    ]
    at org.opencv.imgproc.Imgproc.matchTemplate_0(Native Method)
    at org.opencv.imgproc.Imgproc.matchTemplate(Imgproc.java:7226)
    at com.micaela.myapp.Eye.match(Eye.java:265)
    at com.micaela.myapp.Eye.access$100(Eye.java:22)
    at com.micaela.myapp.Eye$4.run(Eye.java:172)
    at java.lang.Thread.run(Thread.java:856)

I don't understand what is corrsize. The piece of code that throws this exception is:

  Mat res;
  if ((roi.height() > MainActivity.tpl.height()) && (roi.width() > MainActivity.tpl.width())) {
        res = new Mat(new Size(roi.cols() - MainActivity.tpl.cols() + 1, roi.rows() - MainActivity.tpl.rows() + 1), CvType.CV_32FC1);
       if((roi.depth() == CvType.CV_8U || roi.depth() == CvType.CV_32F) && roi.type() == MainActivity.tpl.type()) { //altra eccezione che veniva lanciata!
                Imgproc.matchTemplate(roi, MainActivity.tpl, res, Imgproc.TM_SQDIFF);
                if (left) {
                    return new Point((eyeRect.x + this.roi.width() - matchRect.x - Math.round(Core.minMaxLoc(res).maxLoc.x + (MainActivity.tpl.width() / 2))),
                            (Math.round(Core.minMaxLoc(res).maxLoc.y + (MainActivity.tpl.height() / 2)) + matchRect.y + eyeRect.y));
                } else {
                    return new Point((Math.round(Core.minMaxLoc(res).maxLoc.x + (MainActivity.tpl.width() / 2)) + matchRect.x + eyeRect.x), (Math.round(Core.minMaxLoc(res).maxLoc.y + (MainActivity.tpl.height() / 2)) + matchRect.y + eyeRect.y));
                }
            }
        }

ok, thank you!

Good morning to all. I have imported into Eclipse Juno the sample of OpenCv4Android, ver. 2.4.5, called "cameracontrol". It can be found here:Camera Control OpenCv4Android Sample.

Now I want to use this project as base for mine. I want to process every frame with image-processing techniques, so, in order to improve performance, I want to split the main activity of the project in two classes: one that is merely the activity and one (a thread) that is responsible for preview.

How can I do? Are there any examples about this?

I have created a simple Android application that uses OpenCV4Android to open a video stream and capture frames from it. I have extended the class org.opencv.android.JavaCameraView and, in order to capture frames, this object offers the method onCameraFrame(CvCameraViewFrame inputFrame). If I want to save these frames into a buffer, so with a separate process I can process some of them, how can I do? Which objects should I use to create this buffer?

Good morning. I am using Opencv4Android, ver 2.4.5, with Eclipse Juno. I have imported the opencv tutorial into Eclipse, and I have realized that face-detection sample, camera-control sample, ect, work only in landscape mode. I want to use these projects as base for my application, so I want to make possible to use that applications in all rotations of a device. So, I have found that it's possible to transpose and flip on the fly captured frames, in this way:

@Override
public Mat onCameraFrame(CvCameraViewFrame inputFrame) {
    mRgba = inputFrame.rgba();
    mGray = inputFrame.gray();  

    Display display = ((WindowManager)getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
    int screenOrientation = display.getRotation();
    switch (screenOrientation){
        default:
        case ORIENTATION_0: // Portrait
            Core.flip(mRgba.t(), mRgba, 1);
            break;
        case ORIENTATION_90: // Landscape right
            // do smth.
            break;
        case ORIENTATION_270: // Landscape left
            // do smth.
            break;
    }
    return mRgba;
}

But the only result is that, in portrait mode, now the camera is only a black screen. The error in the logcat is:

05-24 12:05:55.168: ERROR/cv::error()(15219): OpenCV Error: Assertion failed (src.dims == 2 && info.height == (uint32_t)src.rows && info.width == (uint32_t)src.cols) in void Java_org_opencv_android_Utils_nMatToBitmap2(JNIEnv*, jclass, jlong, jobject, jboolean), file /home/reports/ci/slave/50-SDK/opencv/modules/java/generator/src/cpp/utils.cpp, line 97
05-24 12:05:55.168: ERROR/org.opencv.android.Utils(15219): nMatToBitmap catched cv::Exception: /home/reports/ci/slave/50-SDK/opencv/modules/java/generator/src/cpp/utils.cpp:97: error: (-215) src.dims == 2 && info.height == (uint32_t)src.rows && info.width == (uint32_t)src.cols in function void Java_org_opencv_android_Utils_nMatToBitmap2(JNIEnv*, jclass, jlong, jobject, jboolean)
05-24 12:05:55.168: ERROR/CameraBridge(15219): Mat type: Mat [ 720*480*CV_8UC4, isCont=true, isSubmat=false, nativeObj=0x40e1f018, dataAddr=0x774c6010 ]
05-24 12:05:55.168: ERROR/CameraBridge(15219): Bitmap type: 720*480
05-24 12:05:55.168: ERROR/CameraBridge(15219): Utils.matToBitmap() throws an exception: /home/reports/ci/slave/50-SDK/opencv/modules/java/generator/src/cpp/utils.cpp:97: error: (-215) src.dims == 2 && info.height == (uint32_t)src.rows && info.width == (uint32_t)src.cols in function void Java_org_opencv_android_Utils_nMatToBitmap2(JNIEnv*, jclass, jlong, jobject, jboolean)

Please help me, if possible.

Good morning to all. I have created an Android app that opens a video stream, extending the class JavaCameraView. The application should capture frames to process them. I have used, to realize this app, the tutorials contained in the OpenCV4Android package (version 2.4.5). I use Eclipse Juno, and my phone is a samsung s4, and surfing the web I realize that my problem is very common on many devices, including galaxy s,s2,s3,s4. My problem is that my camera, when is opened, in portrait mode results rotated of 90 degrees. It seems to be always in landscape orientation. I have read somewhere that it is possible to flip camera on the fly, but I have not understood how. Could someone help me?

How can I add a button to camera-control opencv4android example? I have simply added in the main.xml file:

<button android:id="@+id/imgShoot" android:text="Capture" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="bottom|right"/> and in OnCreate function, in MainActivity.java, after setContentView:

final Button button = (Button) findViewById(R.id.button_id); button.setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // Perform action on click } }); but it doesn't work. This button should be able to switch between front and back camera, in my device.

I have developed an Android app that, using opencv libraries, opens a video stream and captures frames from it. The problem is that the orientation of the application is portrait, and this allows me to see correctly the menu of the app, but camera is badly rotated (90 degrees to the correct orientation). I use JavaCameraView to open my camera. How can I do?

The problem is that the method: setCameraDisplayOrientation(Activity activity, int cameraId) doesn't work, and the call: this.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_REVERSE_LANDSCAPE) rotates correctly camera but rotates also the menu that becomes badly rotated itself.
This probably because I don't use classes Camera and SurfaceView, but I access the camera through opencv, using the org.opencv.JavaCameraView.