Source code for facereclib.features.Eigenface
#!/usr/bin/env python
# vim: set fileencoding=utf-8 :
# Manuel Guenther <Manuel.Guenther@idiap.ch>
import numpy
import bob.learn.linear
import bob.io.base
from .Extractor import Extractor
from .. import utils
[docs]class Eigenface (Extractor):
"""Extracts grid graphs from the images"""
def __init__(self, subspace_dimension):
# We have to register that this function will need a training step
Extractor.__init__(self, requires_training = True, subspace_dimension = subspace_dimension)
self.m_subspace_dimension = subspace_dimension
[docs] def train(self, image_list, extractor_file):
"""Trains the eigenface extractor using the given list of training images"""
# Initializes an array for the data
data = numpy.vstack([image.flatten() for image in image_list])
utils.info(" -> Training LinearMachine using PCA (SVD)")
t = bob.learn.linear.PCATrainer()
self.m_machine, __eig_vals = t.train(data)
# Machine: get shape, then resize
self.m_machine.resize(self.m_machine.shape[0], self.m_subspace_dimension)
self.m_machine.save(bob.io.base.HDF5File(extractor_file, "w"))
[docs] def load(self, extractor_file):
# read PCA projector
self.m_machine = bob.learn.linear.Machine(bob.io.base.HDF5File(extractor_file))
# Allocates an array for the projected data
self.m_projected_feature = numpy.ndarray(self.m_machine.shape[1], numpy.float64)
def __call__(self, image):
"""Projects the data using the stored covariance matrix"""
# Projects the data
self.m_machine(image.flatten(), self.m_projected_feature)
# return the projected data
return self.m_projected_feature