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//
// This file is auto-generated. Please don't modify it!
//
package org.opencv.face;

import java.util.ArrayList;
import java.util.List;
import org.opencv.core.Algorithm;
import org.opencv.core.Mat;
import org.opencv.core.MatOfInt;
import org.opencv.face.PredictCollector;
import org.opencv.utils.Converters;

// C++: class FaceRecognizer
/**
 * Abstract base class for all face recognition models
 *
 * All face recognition models in OpenCV are derived from the abstract base class FaceRecognizer, which
 * provides a unified access to all face recongition algorithms in OpenCV.
 *
 * ### Description
 *
 * I'll go a bit more into detail explaining FaceRecognizer, because it doesn't look like a powerful
 * interface at first sight. But: Every FaceRecognizer is an Algorithm, so you can easily get/set all
 * model internals (if allowed by the implementation). Algorithm is a relatively new OpenCV concept,
 * which is available since the 2.4 release. I suggest you take a look at its description.
 *
 * Algorithm provides the following features for all derived classes:
 *
 * 
    *
  • * So called "virtual constructor". That is, each Algorithm derivative is registered at program * start and you can get the list of registered algorithms and create instance of a particular * algorithm by its name (see Algorithm::create). If you plan to add your own algorithms, it is * good practice to add a unique prefix to your algorithms to distinguish them from other * algorithms. *
  • *
  • * Setting/Retrieving algorithm parameters by name. If you used video capturing functionality from * OpenCV highgui module, you are probably familar with cv::cvSetCaptureProperty, * ocvcvGetCaptureProperty, VideoCapture::set and VideoCapture::get. Algorithm provides similar * method where instead of integer id's you specify the parameter names as text Strings. See * Algorithm::set and Algorithm::get for details. *
  • *
  • * Reading and writing parameters from/to XML or YAML files. Every Algorithm derivative can store * all its parameters and then read them back. There is no need to re-implement it each time. *
  • *
* * Moreover every FaceRecognizer supports the: * *
    *
  • * Training of a FaceRecognizer with FaceRecognizer::train on a given set of images (your face * database!). *
  • *
  • * Prediction of a given sample image, that means a face. The image is given as a Mat. *
  • *
  • * Loading/Saving the model state from/to a given XML or YAML. *
  • *
  • * Setting/Getting labels info, that is stored as a string. String labels info is useful for * keeping names of the recognized people. *
  • *
* * Note: When using the FaceRecognizer interface in combination with Python, please stick to Python 2. * Some underlying scripts like create_csv will not work in other versions, like Python 3. Setting the * Thresholds +++++++++++++++++++++++ * * Sometimes you run into the situation, when you want to apply a threshold on the prediction. A common * scenario in face recognition is to tell, whether a face belongs to the training dataset or if it is * unknown. You might wonder, why there's no public API in FaceRecognizer to set the threshold for the * prediction, but rest assured: It's supported. It just means there's no generic way in an abstract * class to provide an interface for setting/getting the thresholds of *every possible* FaceRecognizer * algorithm. The appropriate place to set the thresholds is in the constructor of the specific * FaceRecognizer and since every FaceRecognizer is a Algorithm (see above), you can get/set the * thresholds at runtime! * * Here is an example of setting a threshold for the Eigenfaces method, when creating the model: * * * // Let's say we want to keep 10 Eigenfaces and have a threshold value of 10.0 * int num_components = 10; * double threshold = 10.0; * // Then if you want to have a cv::FaceRecognizer with a confidence threshold, * // create the concrete implementation with the appropriate parameters: * Ptr<FaceRecognizer> model = EigenFaceRecognizer::create(num_components, threshold); * * * Sometimes it's impossible to train the model, just to experiment with threshold values. Thanks to * Algorithm it's possible to set internal model thresholds during runtime. Let's see how we would * set/get the prediction for the Eigenface model, we've created above: * * * // The following line reads the threshold from the Eigenfaces model: * double current_threshold = model->getDouble("threshold"); * // And this line sets the threshold to 0.0: * model->set("threshold", 0.0); * * * If you've set the threshold to 0.0 as we did above, then: * * * // * Mat img = imread("person1/3.jpg", IMREAD_GRAYSCALE); * // Get a prediction from the model. Note: We've set a threshold of 0.0 above, * // since the distance is almost always larger than 0.0, you'll get -1 as * // label, which indicates, this face is unknown * int predicted_label = model->predict(img); * // ... * * * is going to yield -1 as predicted label, which states this face is unknown. * * ### Getting the name of a FaceRecognizer * * Since every FaceRecognizer is a Algorithm, you can use Algorithm::name to get the name of a * FaceRecognizer: * * * // Create a FaceRecognizer: * Ptr<FaceRecognizer> model = EigenFaceRecognizer::create(); * // And here's how to get its name: * String name = model->name(); * */ public class FaceRecognizer extends Algorithm { protected FaceRecognizer(long addr) { super(addr); } // internal usage only public static FaceRecognizer __fromPtr__(long addr) { return new FaceRecognizer(addr); } // // C++: void cv::face::FaceRecognizer::train(vector_Mat src, Mat labels) // /** * Trains a FaceRecognizer with given data and associated labels. * * @param src The training images, that means the faces you want to learn. The data has to be * given as a vector<Mat>. * @param labels The labels corresponding to the images have to be given either as a vector<int> * or a Mat of type CV_32SC1. * * The following source code snippet shows you how to learn a Fisherfaces model on a given set of * images. The images are read with imread and pushed into a std::vector<Mat>. The labels of each * image are stored within a std::vector<int> (you could also use a Mat of type CV_32SC1). Think of * the label as the subject (the person) this image belongs to, so same subjects (persons) should have * the same label. For the available FaceRecognizer you don't have to pay any attention to the order of * the labels, just make sure same persons have the same label: * * * // holds images and labels * vector<Mat> images; * vector<int> labels; * // using Mat of type CV_32SC1 * // Mat labels(number_of_samples, 1, CV_32SC1); * // images for first person * images.push_back(imread("person0/0.jpg", IMREAD_GRAYSCALE)); labels.push_back(0); * images.push_back(imread("person0/1.jpg", IMREAD_GRAYSCALE)); labels.push_back(0); * images.push_back(imread("person0/2.jpg", IMREAD_GRAYSCALE)); labels.push_back(0); * // images for second person * images.push_back(imread("person1/0.jpg", IMREAD_GRAYSCALE)); labels.push_back(1); * images.push_back(imread("person1/1.jpg", IMREAD_GRAYSCALE)); labels.push_back(1); * images.push_back(imread("person1/2.jpg", IMREAD_GRAYSCALE)); labels.push_back(1); * * * Now that you have read some images, we can create a new FaceRecognizer. In this example I'll create * a Fisherfaces model and decide to keep all of the possible Fisherfaces: * * * // Create a new Fisherfaces model and retain all available Fisherfaces, * // this is the most common usage of this specific FaceRecognizer: * // * Ptr<FaceRecognizer> model = FisherFaceRecognizer::create(); * * * And finally train it on the given dataset (the face images and labels): * * * // This is the common interface to train all of the available cv::FaceRecognizer * // implementations: * // * model->train(images, labels); * */ public void train(List src, Mat labels) { Mat src_mat = Converters.vector_Mat_to_Mat(src); train_0(nativeObj, src_mat.nativeObj, labels.nativeObj); } // // C++: void cv::face::FaceRecognizer::update(vector_Mat src, Mat labels) // /** * Updates a FaceRecognizer with given data and associated labels. * * @param src The training images, that means the faces you want to learn. The data has to be given * as a vector<Mat>. * @param labels The labels corresponding to the images have to be given either as a vector<int> or * a Mat of type CV_32SC1. * * This method updates a (probably trained) FaceRecognizer, but only if the algorithm supports it. The * Local Binary Patterns Histograms (LBPH) recognizer (see createLBPHFaceRecognizer) can be updated. * For the Eigenfaces and Fisherfaces method, this is algorithmically not possible and you have to * re-estimate the model with FaceRecognizer::train. In any case, a call to train empties the existing * model and learns a new model, while update does not delete any model data. * * * // Create a new LBPH model (it can be updated) and use the default parameters, * // this is the most common usage of this specific FaceRecognizer: * // * Ptr<FaceRecognizer> model = LBPHFaceRecognizer::create(); * // This is the common interface to train all of the available cv::FaceRecognizer * // implementations: * // * model->train(images, labels); * // Some containers to hold new image: * vector<Mat> newImages; * vector<int> newLabels; * // You should add some images to the containers: * // * // ... * // * // Now updating the model is as easy as calling: * model->update(newImages,newLabels); * // This will preserve the old model data and extend the existing model * // with the new features extracted from newImages! * * * Calling update on an Eigenfaces model (see EigenFaceRecognizer::create), which doesn't support * updating, will throw an error similar to: * * * OpenCV Error: The function/feature is not implemented (This FaceRecognizer (FaceRecognizer.Eigenfaces) does not support updating, you have to use FaceRecognizer::train to update it.) in update, file /home/philipp/git/opencv/modules/contrib/src/facerec.cpp, line 305 * terminate called after throwing an instance of 'cv::Exception' * * * Note: The FaceRecognizer does not store your training images, because this would be very * memory intense and it's not the responsibility of te FaceRecognizer to do so. The caller is * responsible for maintaining the dataset, he want to work with. */ public void update(List src, Mat labels) { Mat src_mat = Converters.vector_Mat_to_Mat(src); update_0(nativeObj, src_mat.nativeObj, labels.nativeObj); } // // C++: int cv::face::FaceRecognizer::predict(Mat src) // public int predict_label(Mat src) { return predict_label_0(nativeObj, src.nativeObj); } // // C++: void cv::face::FaceRecognizer::predict(Mat src, int& label, double& confidence) // /** * Predicts a label and associated confidence (e.g. distance) for a given input image. * * @param src Sample image to get a prediction from. * @param label The predicted label for the given image. * @param confidence Associated confidence (e.g. distance) for the predicted label. * * The suffix const means that prediction does not affect the internal model state, so the method can * be safely called from within different threads. * * The following example shows how to get a prediction from a trained model: * * * using namespace cv; * // Do your initialization here (create the cv::FaceRecognizer model) ... * // ... * // Read in a sample image: * Mat img = imread("person1/3.jpg", IMREAD_GRAYSCALE); * // And get a prediction from the cv::FaceRecognizer: * int predicted = model->predict(img); * * * Or to get a prediction and the associated confidence (e.g. distance): * * * using namespace cv; * // Do your initialization here (create the cv::FaceRecognizer model) ... * // ... * Mat img = imread("person1/3.jpg", IMREAD_GRAYSCALE); * // Some variables for the predicted label and associated confidence (e.g. distance): * int predicted_label = -1; * double predicted_confidence = 0.0; * // Get the prediction and associated confidence from the model * model->predict(img, predicted_label, predicted_confidence); * */ public void predict(Mat src, int[] label, double[] confidence) { double[] label_out = new double[1]; double[] confidence_out = new double[1]; predict_0(nativeObj, src.nativeObj, label_out, confidence_out); if(label!=null) label[0] = (int)label_out[0]; if(confidence!=null) confidence[0] = (double)confidence_out[0]; } // // C++: void cv::face::FaceRecognizer::predict(Mat src, Ptr_PredictCollector collector) // /** *
    *
  • * if implemented - send all result of prediction to collector that can be used for somehow custom result handling * @param src Sample image to get a prediction from. * @param collector User-defined collector object that accepts all results *
  • *
* * To implement this method u just have to do same internal cycle as in predict(InputArray src, CV_OUT int &label, CV_OUT double &confidence) but * not try to get "best@ result, just resend it to caller side with given collector */ public void predict_collect(Mat src, PredictCollector collector) { predict_collect_0(nativeObj, src.nativeObj, collector.getNativeObjAddr()); } // // C++: void cv::face::FaceRecognizer::write(String filename) // /** * Saves a FaceRecognizer and its model state. * * Saves this model to a given filename, either as XML or YAML. * @param filename The filename to store this FaceRecognizer to (either XML/YAML). * * Every FaceRecognizer overwrites FaceRecognizer::save(FileStorage& fs) to save the internal model * state. FaceRecognizer::save(const String& filename) saves the state of a model to the given * filename. * * The suffix const means that prediction does not affect the internal model state, so the method can * be safely called from within different threads. */ public void write(String filename) { write_0(nativeObj, filename); } // // C++: void cv::face::FaceRecognizer::read(String filename) // /** * Loads a FaceRecognizer and its model state. * * Loads a persisted model and state from a given XML or YAML file . Every FaceRecognizer has to * overwrite FaceRecognizer::load(FileStorage& fs) to enable loading the model state. * FaceRecognizer::load(FileStorage& fs) in turn gets called by * FaceRecognizer::load(const String& filename), to ease saving a model. * @param filename automatically generated */ public void read(String filename) { read_0(nativeObj, filename); } // // C++: void cv::face::FaceRecognizer::setLabelInfo(int label, String strInfo) // /** * Sets string info for the specified model's label. * * The string info is replaced by the provided value if it was set before for the specified label. * @param label automatically generated * @param strInfo automatically generated */ public void setLabelInfo(int label, String strInfo) { setLabelInfo_0(nativeObj, label, strInfo); } // // C++: String cv::face::FaceRecognizer::getLabelInfo(int label) // /** * Gets string information by label. * * If an unknown label id is provided or there is no label information associated with the specified * label id the method returns an empty string. * @param label automatically generated * @return automatically generated */ public String getLabelInfo(int label) { return getLabelInfo_0(nativeObj, label); } // // C++: vector_int cv::face::FaceRecognizer::getLabelsByString(String str) // /** * Gets vector of labels by string. * * The function searches for the labels containing the specified sub-string in the associated string * info. * @param str automatically generated * @return automatically generated */ public MatOfInt getLabelsByString(String str) { return MatOfInt.fromNativeAddr(getLabelsByString_0(nativeObj, str)); } @Override protected void finalize() throws Throwable { delete(nativeObj); } // C++: void cv::face::FaceRecognizer::train(vector_Mat src, Mat labels) private static native void train_0(long nativeObj, long src_mat_nativeObj, long labels_nativeObj); // C++: void cv::face::FaceRecognizer::update(vector_Mat src, Mat labels) private static native void update_0(long nativeObj, long src_mat_nativeObj, long labels_nativeObj); // C++: int cv::face::FaceRecognizer::predict(Mat src) private static native int predict_label_0(long nativeObj, long src_nativeObj); // C++: void cv::face::FaceRecognizer::predict(Mat src, int& label, double& confidence) private static native void predict_0(long nativeObj, long src_nativeObj, double[] label_out, double[] confidence_out); // C++: void cv::face::FaceRecognizer::predict(Mat src, Ptr_PredictCollector collector) private static native void predict_collect_0(long nativeObj, long src_nativeObj, long collector_nativeObj); // C++: void cv::face::FaceRecognizer::write(String filename) private static native void write_0(long nativeObj, String filename); // C++: void cv::face::FaceRecognizer::read(String filename) private static native void read_0(long nativeObj, String filename); // C++: void cv::face::FaceRecognizer::setLabelInfo(int label, String strInfo) private static native void setLabelInfo_0(long nativeObj, int label, String strInfo); // C++: String cv::face::FaceRecognizer::getLabelInfo(int label) private static native String getLabelInfo_0(long nativeObj, int label); // C++: vector_int cv::face::FaceRecognizer::getLabelsByString(String str) private static native long getLabelsByString_0(long nativeObj, String str); // native support for java finalize() private static native void delete(long nativeObj); }




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