Beispiel #1
0
def train_by_images(path, db_file_name, params=None):
    """
    Train an LBP face recognizer by using captions in images

    :type path: string
    :param path: path of directory with images

    :type db_file_name: string
    :param db_file_name: path of file that will contain the face models

    :type params: dictionary
    :param params: configuration parameters (see table)

    :rtype: tuple
    :return: a (model, tags) tuple, where model is an LBPHFaceRecognizer
             and tags is the list of found tags

    ============================================  ========================================  =============================
    Key                                           Value                                     Default value
    ============================================  ========================================  =============================
    LBP_grid_x                                    Number of columns in grid                 4
                                                  used for calculating LBP
    LBP_grid_y                                    Number of columns in grid                 8
                                                  used for calculating LBP
    LBP_neighbors                                 Number of neighbors                       8
                                                  used for calculating LBP
    LBP_radius                                    Radius used                               1
                                                  for calculating LBP (in pixels)
    use_one_file_for_face_models                  If True, use one file for face models     True
    align_path                                    Path of directory
                                                  where aligned faces are saved
    check_eye_positions                           If True, check eye positions              True
    classifiers_dir_path                          Path of directory with OpenCV
                                                  cascade classifiers
    eye_detection_classifier                      Classifier for eye detection              'haarcascade_mcs_lefteye.xml'
    face_detection_algorithm                      Classifier for face detection             'HaarCascadeFrontalFaceAlt2'
                                                  ('HaarCascadeFrontalFaceAlt',
                                                   'HaarCascadeFrontalFaceAltTree',
                                                   'HaarCascadeFrontalFaceAlt2',
                                                   'HaarCascadeFrontalFaceDefault',
                                                   'HaarCascadeProfileFace',
                                                   'HaarCascadeFrontalAndProfileFaces',
                                                   'HaarCascadeFrontalAndProfileFaces2',
                                                   'LBPCascadeFrontalface',
                                                   'LBPCascadeProfileFace' or
                                                   'LBPCascadeFrontalAndProfileFaces')
    flags                                         Flags used in face detection              'DoCannyPruning'
                                                  ('DoCannyPruning', 'ScaleImage',
                                                  'FindBiggestObject', 'DoRoughSearch').
                                                  If 'DoCannyPruning' is used, regions
                                                  that do not contain lines are discarded.
                                                  If 'ScaleImage' is used, image instead
                                                  of the detector is scaled
                                                  (it can be advantegeous in terms of
                                                  memory and cache use).
                                                  If 'FindBiggestObject' is used,
                                                  only the biggest object is returned
                                                  by the detector.
                                                  'DoRoughSearch', used together with
                                                  'FindBiggestObject',
                                                  terminates the search as soon as
                                                  the first candidate object is found
    min_neighbors                                 Mininum number of neighbor bounding       5
                                                  boxes for retaining face detection
    min_size_height                               Minimum height of face detection          20
                                                  bounding box (in pixels)
    min_size_width                                Minimum width of face detection           20
                                                  bounding box (in pixels)
    scale_factor                                  Scale factor between two scans            1.1
                                                  in face detection
    max_eye_angle                                 Maximum inclination of the line           0.125
                                                  connecting the eyes
                                                  (in % of pi radians)
    min_eye_distance                              Minimum distance between eyes             0.25
                                                  (in % of the width of the face
                                                  bounding box)
    nose_detection_classifier                     Classifier for nose detection             'haarcascade_mcs_nose.xml'
    software_test_file                            Path of image to be used for
                                                  software test
    use_nose_pos_in_detection                     If True, detections with no good          False
                                                  nose position are discarded
    lev_ratio_pct_threshold                       Minimum threshold for considering         0.8
                                                  captions in frame
    min_tag_length                                Minimum length of tags considered         10
                                                  in caption recognition
    tags_file_path                                Path of text file containing
                                                  list of tags
    tesseract_parent_dir_path                     Path of directory containing
                                                  'tesseract' directory
    use_blacklist                                 If True, use blacklist of items           True
                                                  that make the results of the
                                                  caption recognition on a frame
                                                  rejected
    use_levenshtein                               If True, words found in image             True
                                                  by caption recognition and tags
                                                  are compared by using
                                                  the Levenshtein distance
    ============================================  ========================================  =============================
    """

    # Set parameters
    lbp_radius = c.LBP_RADIUS
    lbp_neighbors = c.LBP_NEIGHBORS
    lbp_grid_x = c.LBP_GRID_X
    lbp_grid_y = c.LBP_GRID_Y
    use_one_file = ce.USE_ONE_FILE_FOR_FACE_MODELS
    if params:
        if c.LBP_RADIUS_KEY in params:
            lbp_radius = params[c.LBP_RADIUS_KEY]
        if c.LBP_NEIGHBORS_KEY in params:
            lbp_radius = params[c.LBP_NEIGHBORS_KEY]
        if c.LBP_GRID_X_KEY in params:
            lbp_radius = params[c.LBP_GRID_X]
        if c.LBP_GRID_Y_KEY in params:
            lbp_radius = params[c.LBP_GRID_Y_KEY]
        if ce.USE_ONE_FILE_FOR_FACE_MODELS_KEY in params:
            use_one_file = params[ce.USE_ONE_FILE_FOR_FACE_MODELS_KEY]

    # Save processing time
    start_time = cv2.getTickCount()
    
    model = None
    
    X, y = [], []
    tags = {}
    
    image_counter = 0
     
    for image in os.listdir(path):
    
        image_complete_path = path + os.sep + image
                
        [label, tag, face] = analyze_image(image_complete_path, params)
        
        if label != -1:
            
            X.append(np.asarray(face, dtype=np.uint8))
            y.append(label)
            tags[label] = tag

            image_counter += 1
    
    # Save file with face models
    
    if use_one_file:
            
        model = cv2.createLBPHFaceRecognizer(
        lbp_radius,
        lbp_neighbors,
        lbp_grid_x,
        lbp_grid_y)
        model.train(np.asarray(X), np.asarray(y))
        model.save(db_file_name)
        
    else:
        
        y_set = set(y)
            
        for label in y_set:
            
            person_X = []
            person_y = []
            
            for i in range(0, len(y)):
                
                if y[i] == label:
                    
                    person_X.append(X[i])
                    person_y.append(label)
                       
            save_model_file(person_X, person_y, params, db_file_name)
    
    # Save labels in YAML file
    save_YAML_file(db_file_name + "-Tags", tags)     
        
    # Calculate processing time in seconds
    time_in_clocks = cv2.getTickCount() - start_time
    time_in_s = time_in_clocks / cv2.getTickFrequency()
    
    print('Creation time: ' + str(time_in_s) + ' s\n')
    
    return model, tags
                            self._params[ce.TRAINING_IMAGES_NR_KEY])
                    
                    if((not already_div) and
                           (file_counter >= training_images_nr)):
                        # Number of training images has been reached
                        break

                use_one_file = ce.USE_ONE_FILE_FOR_FACE_MODELS
        
                if self._params is not None:
                    
                    use_one_file = (
                        self._params[ce.USE_ONE_FILE_FOR_FACE_MODELS_KEY])
                
                if not use_one_file:
                    save_model_file(X, y)
                    X, y = [], []

                l += 1
        return [X, y]

    def read_images(self, path, sz=None):
        """
        Reads the images in a given folder,
        resizes images on the fly if size is given.

        :type path: String
        :param path: Path to a folder with subfolders
                    representing the subjects (people)

        :type sz: tuple