Tools implemented in bob.bio.face¶
Summary¶
Databases¶
bob.bio.face.database.ARFaceBioDatabase ([…]) |
ARFace database implementation of bob.bio.base.database.BioDatabase interface. |
bob.bio.face.database.AtntBioDatabase ([…]) |
ATNT database implementation of bob.bio.base.database.BioDatabase interface. |
bob.bio.face.database.BancaBioDatabase ([…]) |
BANCA database implementation of bob.bio.base.database.ZTBioDatabase interface. |
bob.bio.face.database.MobioBioDatabase ([…]) |
MOBIO database implementation of bob.bio.base.database.ZTBioDatabase interface. |
bob.bio.face.database.CaspealBioDatabase ([…]) |
Caspeal database implementation of bob.bio.base.database.BioDatabase interface. |
bob.bio.face.database.ReplayBioDatabase (**kwargs) |
Replay attack database implementation of bob.bio.base.database.BioDatabase interface. |
bob.bio.face.database.ReplayMobileBioDatabase ([…]) |
ReplayMobile database implementation of bob.bio.base.database.BioDatabase interface. |
bob.bio.face.database.MsuMfsdModBioDatabase ([…]) |
MsuMfsdMod database implementation of bob.bio.base.database.BioDatabase interface. |
bob.bio.face.database.GBUBioDatabase ([…]) |
GBU database implementation of bob.bio.base.database.BioDatabase interface. |
bob.bio.face.database.LFWBioDatabase ([…]) |
LFW database implementation of bob.bio.base.database.Database interface. |
bob.bio.face.database.MultipieBioDatabase ([…]) |
Multipie database implementation of bob.bio.base.database.Database interface. |
bob.bio.face.database.IJBABioDatabase ([…]) |
IJBA database implementation of bob.bio.base.database.BioDatabase interface. |
bob.bio.face.database.XM2VTSBioDatabase ([…]) |
XM2VTS database implementation of bob.bio.base.database.Database interface. |
bob.bio.face.database.FRGCBioDatabase ([…]) |
FRGC database implementation of bob.bio.base.database.BioDatabase interface. |
bob.bio.face.database.SCFaceBioDatabase ([…]) |
SCFace database implementation of bob.bio.base.database.ZTDatabase interface. |
Face Image Annotators¶
bob.bio.face.annotator.Base (**kwargs) |
Base class for all face annotators |
bob.bio.face.annotator.BobIpFacedetect ([…]) |
Annotator using bob.ip.facedetect Provides topleft and bottomright annoations. |
bob.bio.face.annotator.BobIpFlandmark (**kwargs) |
Annotator using bob.ip.flandmark. |
bob.bio.face.annotator.BobIpDlib (**kwargs) |
Annotator using bob.ip.dlib |
bob.bio.face.annotator.BobIpMTCNN (**kwargs) |
Annotator using bob.ip.mtcnn |
Image Preprocessors¶
bob.bio.face.preprocessor.Base ([dtype, …]) |
Performs color space adaptations and data type corrections for the given image. |
bob.bio.face.preprocessor.FaceCrop (…[, …]) |
Crops the face according to the given annotations. |
bob.bio.face.preprocessor.FaceDetect (…[, …]) |
Performs a face detection (and facial landmark localization) in the given image and crops the face. |
bob.bio.face.preprocessor.TanTriggs (face_cropper) |
Crops the face (if desired) and applies Tan&Triggs algorithm [TT10] to photometrically enhance the image. |
bob.bio.face.preprocessor.HistogramEqualization (…) |
Crops the face (if desired) and performs histogram equalization to photometrically enhance the image. |
bob.bio.face.preprocessor.SelfQuotientImage (…) |
Crops the face (if desired) and applies self quotient image algorithm [WLW04] to photometrically enhance the image. |
bob.bio.face.preprocessor.INormLBP (face_cropper) |
Performs I-Norm LBP on the given image |
Image Feature Extractors¶
bob.bio.face.extractor.Eigenface (…) |
Performs a principal component analysis (PCA) on the given data. |
bob.bio.face.extractor.DCTBlocks ([…]) |
Extracts Discrete Cosine Transform (DCT) features from (overlapping) image blocks. |
bob.bio.face.extractor.GridGraph ([…]) |
Extracts Gabor jets in a grid structure [GHW12] using functionalities from bob.ip.gabor. |
bob.bio.face.extractor.LGBPHS (block_size[, …]) |
Extracts Local Gabor Binary Pattern Histogram Sequences (LGBPHS) [ZSG05] from the images, using functionality from bob.ip.base and bob.ip.gabor. |
Face Recognition Algorithms¶
bob.bio.face.algorithm.GaborJet (…[, …]) |
Computes a comparison of lists of Gabor jets using a similarity function of bob.ip.gabor.Similarity . |
bob.bio.face.algorithm.Histogram ([…]) |
Computes the distance between histogram sequences. |
Databases¶
-
class
bob.bio.face.database.
ARFaceBioDatabase
(original_directory=None, original_extension='.ppm', **kwargs)¶ Bases:
bob.bio.base.database.BioDatabase
ARFace database implementation of
bob.bio.base.database.BioDatabase
interface. It is an extension of an SQL-based database interface, which directly talks to ARFACE database, for verification experiments (good to use in bob.bio.base framework).-
original_directory
¶
-
-
class
bob.bio.face.database.
AtntBioDatabase
(original_directory=None, original_extension='.pgm', **kwargs)¶ Bases:
bob.bio.base.database.BioDatabase
ATNT database implementation of
bob.bio.base.database.BioDatabase
interface. It is an extension of the database interface, which directly talks to ATNT database, for verification experiments (good to use in bob.bio.base framework).
-
class
bob.bio.face.database.
BancaBioDatabase
(original_directory=None, original_extension=None, **kwargs)¶ Bases:
bob.bio.base.database.ZTBioDatabase
BANCA database implementation of
bob.bio.base.database.ZTBioDatabase
interface. It is an extension of an SQL-based database interface, which directly talks to Banca database, for verification experiments (good to use in bob.bio.base framework).-
original_directory
¶
-
-
class
bob.bio.face.database.
CaspealBioDatabase
(original_directory=None, original_extension='.tif', **kwargs)¶ Bases:
bob.bio.base.database.BioDatabase
Caspeal database implementation of
bob.bio.base.database.BioDatabase
interface. It is an extension of an SQL-based database interface, which directly talks to Caspeal database, for verification experiments (good to use in bob.bio.base framework).-
original_directory
¶
-
-
class
bob.bio.face.database.
FRGCBioDatabase
(original_directory=None, original_extension='.jpg', **kwargs)¶ Bases:
bob.bio.base.database.BioDatabase
FRGC database implementation of
bob.bio.base.database.BioDatabase
interface. It is an extension of the low-level database interface, which directly talks to FRGC database, for verification experiments (good to use in bob.bio.base framework).-
original_directory
¶
-
-
class
bob.bio.face.database.
FaceBioFile
(client_id, path, file_id, **kwargs)¶
-
class
bob.bio.face.database.
GBUBioDatabase
(original_directory=None, original_extension='.jpg', **kwargs)¶ Bases:
bob.bio.base.database.BioDatabase
GBU database implementation of
bob.bio.base.database.BioDatabase
interface. It is an extension of an SQL-based database interface, which directly talks to GBU database, for verification experiments (good to use in bob.bio.base framework).-
original_directory
¶
-
-
class
bob.bio.face.database.
IJBABioDatabase
(original_directory=None, annotation_directory=None, original_extension=None, **kwargs)¶ Bases:
bob.bio.base.database.BioDatabase
IJBA database implementation of
bob.bio.base.database.BioDatabase
interface. It is an extension of an SQL-based database interface, which directly talks to IJBA database, for verification experiments (good to use in bob.bio.base framework).-
annotation_directory
¶
-
original_directory
¶
-
-
class
bob.bio.face.database.
IJBBBioDatabase
(original_directory=None, annotation_directory=None, original_extension=None, **kwargs)¶ Bases:
bob.bio.base.database.BioDatabase
IJBB database implementation of
bob.bio.base.database.BioDatabase
interface. It is an extension of an SQL-based database interface, which directly talks to IJBB database, for verification experiments (good to use in bob.bio.base framework).-
annotation_directory
¶
-
original_directory
¶
-
-
class
bob.bio.face.database.
IJBCBioDatabase
(original_directory=None, annotation_directory=None, original_extension=None, **kwargs)¶ Bases:
bob.bio.base.database.BioDatabase
IJBC database implementation of
bob.bio.base.database.BioDatabase
interface. It is an extension of an SQL-based database interface, which directly talks to IJBC database, for verification experiments (good to use in bob.bio.base framework).-
annotation_directory
¶
-
original_directory
¶
-
-
class
bob.bio.face.database.
LFWBioDatabase
(original_directory=None, original_extension='.jpg', annotation_type=None, **kwargs)¶ Bases:
bob.bio.base.database.BioDatabase
LFW database implementation of bob.bio.base.database.Database interface. It is an extension of an SQL-based database interface, which directly talks to LFW database, for verification experiments (good to use in bob.bio.base framework).
-
client_id_from_model_id
(model_id, group='dev')[source]¶ Return the client id associated with the given model id. In this base class implementation, it is assumed that only one model is enrolled for each client and, thus, client id and model id are identical. All key word arguments are ignored. Please override this function in derived class implementations to change this behavior.
-
original_directory
¶
-
-
class
bob.bio.face.database.
MobioBioDatabase
(original_directory=None, original_extension=None, annotation_directory=None, annotation_extension='.pos', **kwargs)¶ Bases:
bob.bio.base.database.ZTBioDatabase
MOBIO database implementation of bob.bio.base.database.ZTBioDatabase interface. It is an extension of an SQL-based database interface, which directly talks to Mobio database, for verification experiments (good to use in bob.bio.base framework).
-
annotation_directory
¶
-
original_directory
¶
-
-
class
bob.bio.face.database.
MsuMfsdModBioDatabase
(max_number_of_frames=None, **kwargs)¶ Bases:
bob.bio.base.database.BioDatabase
MsuMfsdMod database implementation of
bob.bio.base.database.BioDatabase
interface. It is an extension of an SQL-based database interface, which directly talks to MsuMfsdMod database, for verification experiments (good to use in bob.bio.base framework).-
original_directory
¶
-
-
class
bob.bio.face.database.
MultipieBioDatabase
(original_directory=None, original_extension='.png', annotation_directory=None, annotation_extension='.pos', **kwargs)¶ Bases:
bob.bio.base.database.ZTBioDatabase
Multipie database implementation of bob.bio.base.database.Database interface. It is an extension of an SQL-based database interface, which directly talks to Multipie database, for verification experiments (good to use in bob.bio.base framework).
-
original_directory
¶
-
-
class
bob.bio.face.database.
ReplayBioDatabase
(**kwargs)¶ Bases:
bob.bio.base.database.BioDatabase
Replay attack database implementation of bob.bio.base.database.BioDatabase interface. It is an extension of an SQL-based database interface, which directly talks to Replay database, for verification experiments (good to use in bob.bio.base framework). It also implements a kind of hack so that you can run vulnerability analysis with it.
-
original_directory
¶
-
-
class
bob.bio.face.database.
ReplayMobileBioDatabase
(max_number_of_frames=None, **kwargs)¶ Bases:
bob.bio.base.database.BioDatabase
ReplayMobile database implementation of
bob.bio.base.database.BioDatabase
interface. It is an extension of an SQL-based database interface, which directly talks to ReplayMobile database, for verification experiments (good to use in bob.bio.base framework).-
original_directory
¶
-
-
class
bob.bio.face.database.
SCFaceBioDatabase
(original_directory=None, original_extension='.jpg', **kwargs)¶ Bases:
bob.bio.base.database.ZTBioDatabase
SCFace database implementation of bob.bio.base.database.ZTDatabase interface. It is an extension of an SQL-based database interface, which directly talks to SCFace database, for verification experiments (good to use in bob.bio.base framework).
-
original_directory
¶
-
-
class
bob.bio.face.database.
XM2VTSBioDatabase
(original_directory=None, original_extension='.ppm', **kwargs)¶ Bases:
bob.bio.base.database.BioDatabase
XM2VTS database implementation of bob.bio.base.database.Database interface. It is an extension of an SQL-based database interface, which directly talks to XM2VTS database, for verification experiments (good to use in bob.bio.base framework).
-
original_directory
¶
-
Annotators¶
-
bob.bio.face.annotator.
bounding_box_to_annotations
(bbx)[source]¶ Converts
bob.ip.facedetect.BoundingBox
to dictionary annotations.Parameters: bbx ( bob.ip.facedetect.BoundingBox
) – The given bounding box.Returns: A dictionary with topleft and bottomright keys. Return type: dict
-
bob.bio.face.annotator.
min_face_size_validator
(annotations, min_face_size=(32, 32))[source]¶ Validates annotations based on face’s minimal size.
Parameters: Returns: True, if the face is large enough.
Return type:
-
class
bob.bio.face.annotator.
Base
(**kwargs)¶ Bases:
bob.bio.base.annotator.Annotator
Base class for all face annotators
-
annotate
(sample, **kwargs)[source]¶ Annotates an image and returns annotations in a dictionary. All annotator should return at least the
topleft
andbottomright
coordinates. Some currently known annotation points such asreye
andleye
are formalized inbob.bio.face.preprocessor.FaceCrop
.Parameters: - sample (numpy.ndarray) – The image should be a Bob format (#Channels, Height, Width) RGB image.
- **kwargs – The extra arguments that may be passed.
-
-
class
bob.bio.face.annotator.
BobIpDlib
(**kwargs)¶ Bases:
bob.bio.face.annotator.Base
Annotator using bob.ip.dlib
-
annotate
(image, **kwargs)[source]¶ Annotates an image using bob.ip.dlib
Parameters: - image (numpy.array) – An RGB image in Bob format.
- **kwargs – Ignored.
Returns: Annotations contain: (topleft, bottomright, leye, reye, nose, mouthleft, mouthright).
Return type:
-
-
class
bob.bio.face.annotator.
BobIpFacedetect
(cascade=None, detection_overlap=0.2, distance=2, scale_base=0.9576032806985737, lowest_scale=0.125, eye_estimate=False, **kwargs)¶ Bases:
bob.bio.face.annotator.Base
Annotator using bob.ip.facedetect Provides topleft and bottomright annoations.
Parameters: - cascade (
bob.ip.facedetect.Cascade
) – The file name, where a face detector cascade can be found. IfNone
, the default cascade for frontal facesbob.ip.facedetect.default_cascade
is used. - detection_overlap (float) – See
bob.ip.facedetect.detect_single_face
. - distance (int) – See the Sampling section in the Users Guide of bob.ip.facedetect.
- scale_base (float) – See the Sampling section in the Users Guide of bob.ip.facedetect.
- lowest_scale (float) – See the Sampling section in the Users Guide of bob.ip.facedetect.
- eye_estimate (bool) – If
True
, expected eye locations are added to the annotations.
- cascade (
-
class
bob.bio.face.annotator.
BobIpFlandmark
(**kwargs)¶ Bases:
bob.bio.face.annotator.Base
Annotator using bob.ip.flandmark. This annotator needs the topleft and bottomright annotations provided.
Example usage:
>>> from bob.bio.base.annotator import FailSafe >>> from bob.bio.face.annotator import ( ... BobIpFacedetect, BobIpFlandmark) >>> annotator = FailSafe( ... [BobIpFacedetect(), BobIpFlandmark()], ... required_keys=('reye', 'leye'))
-
class
bob.bio.face.annotator.
BobIpMTCNN
(**kwargs)¶ Bases:
bob.bio.face.annotator.Base
Annotator using bob.ip.mtcnn
-
annotate
(image, **kwargs)[source]¶ Annotates an image using bob.ip.mtcnn
Parameters: - image (numpy.array) – An RGB image in Bob format.
- **kwargs – Ignored.
Returns: Annotations contain: (topleft, bottomright, leye, reye, nose, mouthleft, mouthright).
Return type:
-
Preprocessors¶
-
class
bob.bio.face.preprocessor.
Base
(dtype=None, color_channel='gray', **kwargs)¶ Bases:
bob.bio.base.preprocessor.Preprocessor
Performs color space adaptations and data type corrections for the given image.
Parameters:
- dtype :
numpy.dtype
or convertible orNone
- The data type that the resulting image will have.
- color_channel : one of
('gray', 'red', 'gren', 'blue', 'rgb')
- The specific color channel, which should be extracted from the image.
-
color_channel
(image) → channel[source]¶ Returns the channel of the given image, which was selected in the constructor. Currently, gray, red, green and blue channels are supported.
Parameters:
- image : 2D or 3D
numpy.ndarray
- The image to get the specified channel from.
Returns:
- channel : 2D or 3D
numpy.ndarray
- The extracted color channel.
- image : 2D or 3D
-
data_type
(image) → image[source]¶ Converts the given image into the data type specified in the constructor of this class. If no data type was specified, or the
image
isNone
, no conversion is performed.Parameters:
- image : 2D or 3D
numpy.ndarray
- The image to convert.
Returns:
- image : 2D or 3D
numpy.ndarray
- The image converted to the desired data type, if any.
- image : 2D or 3D
- dtype :
-
class
bob.bio.face.preprocessor.
FaceCrop
(cropped_image_size, cropped_positions, fixed_positions=None, mask_sigma=None, mask_neighbors=5, mask_seed=None, annotator=None, **kwargs)¶ Bases:
bob.bio.face.preprocessor.Base
Crops the face according to the given annotations.
This class is designed to perform a geometric normalization of the face based on the eye locations, using
bob.ip.base.FaceEyesNorm
. Usually, when executing thecrop_face()
function, the image and the eye locations have to be specified. There, the given image will be transformed such that the eye locations will be placed at specific locations in the resulting image. These locations, as well as the size of the cropped image, need to be specified in the constructor of this class, ascropped_positions
andcropped_image_size
.Some image databases do not provide eye locations, but rather bounding boxes. This is not a problem at all. Simply define the coordinates, where you want your
cropped_positions
to be in the cropped image, by specifying the same keys in the dictionary that will be given asannotations
to thecrop_face()
function.Note
These locations can even be outside of the cropped image boundary, i.e., when the crop should be smaller than the annotated bounding boxes.
Sometimes, databases provide pre-cropped faces, where the eyes are located at (almost) the same position in all images. Usually, the cropping does not conform with the cropping that you like (i.e., image resolution is wrong, or too much background information). However, the database does not provide eye locations (since they are almost identical for all images). In that case, you can specify the
fixed_positions
in the constructor, which will be taken instead of theannotations
inside thecrop_face()
function (in which case theannotations
are ignored).Sometimes, the crop of the face is outside of the original image boundaries. Usually, these pixels will simply be left black, resulting in sharp edges in the image. However, some feature extractors do not like these sharp edges. In this case, you can set the
mask_sigma
to copy pixels from the valid border of the image and add random noise (seebob.ip.base.extrapolate_mask()
).Parameters: - cropped_image_size ((int, int)) – The resolution of the cropped image, in order (HEIGHT,WIDTH); if not given, no face cropping will be performed
- cropped_positions (dict) – The coordinates in the cropped image, where the annotated points should be
put to. This parameter is a dictionary with usually two elements, e.g.,
{'reye':(RIGHT_EYE_Y, RIGHT_EYE_X) , 'leye':(LEFT_EYE_Y, LEFT_EYE_X)}
. However, also other parameters, such as{'topleft' : ..., 'bottomright' : ...}
are supported, as long as theannotations
in the __call__ function are present. - fixed_positions (dict or None) – If specified, ignore the annotations from the database and use these fixed positions throughout.
- mask_sigma (float or None) – Fill the area outside of image boundaries with random pixels from the
border, by adding noise to the pixel values. To disable extrapolation, set
this value to
None
. To disable adding random noise, set it to a negative value or 0. - mask_neighbors (int) – The number of neighbors used during mask extrapolation. See
bob.ip.base.extrapolate_mask()
for details. - mask_seed (int or None) –
The random seed to apply for mask extrapolation.
Warning
When run in parallel, the same random seed will be applied to all parallel processes. Hence, results of parallel execution will differ from the results in serial execution.
- annotator (
bob.bio.base.annotator.Annotator
) – If provided, the annotator will be used if the required annotations are missing. - kwargs – Remaining keyword parameters passed to the
Base
constructor, such ascolor_channel
ordtype
.
-
crop_face
(image, annotations=None)[source]¶ Crops the face. Executes the face cropping on the given image and returns the cropped version of it.
Parameters: - image (2D
numpy.ndarray
) – The face image to be processed. - annotations (dict or
None
) – The annotations that fit to the given image.None
is only accepted, whenfixed_positions
were specified in the constructor.
Returns: face – The cropped face.
Return type: 2D
numpy.ndarray
(float)Raises: ValueError
– If the annotations is None.- image (2D
-
class
bob.bio.face.preprocessor.
FaceDetect
(face_cropper, cascade=None, use_flandmark=False, detection_overlap=0.2, distance=2, scale_base=0.9576032806985737, lowest_scale=0.125, **kwargs)¶ Bases:
bob.bio.face.preprocessor.Base
Performs a face detection (and facial landmark localization) in the given image and crops the face.
This class is designed to perform a geometric normalization of the face based on the detected face. Face detection is performed using bob.ip.facedetect. Particularly, the function
bob.ip.facedetect.detect_single_face()
is executed, which will always return exactly one bounding box, even if the image contains more than one face, or no face at all. The speed of the face detector can be regulated using thecascade
,distance` ``scale_base
andlowest_scale
parameters. The number of overlapping detected bounding boxes that should be joined can be selected bydetection_overlap
. Please see the documentation of bob.ip.facedetect for more details about these parameters.Additionally, facial landmarks can be detected using the Python Bindings to the Flandmark Keypoint Localizer for Frontal Faces. If enabled using
use_flandmark = True
in the constructor, it is tried to obtain the facial landmarks inside the detected facial area. If landmarks are found, these are used to geometrically normalize the face. Otherwise, the eye locations are estimated based on the bounding box. This is also applied, whenuse_flandmark = False.
The face cropping itself is done by the given
face_cropper
. This cropper can either be an instance ofFaceCrop
(or any other class that provides a similarcrop_face
function), or it can be the resource name of a face cropper, such as'face-crop-eyes'
.Parameters:
- face_cropper :
bob.bio.face.preprocessor.FaceCrop
or str - The face cropper to be used to crop the detected face.
Might be an instance of a
FaceCrop
or the name of a face cropper resource. - cascade : str or
None
- The file name, where a face detector cascade can be found.
If
None
, the default cascade for frontal facesbob.ip.facedetect.default_cascade()
is used. - use_flandmark : bool
- If selected,
bob.ip.flandmark.Flandmark
is used to detect the eye locations. Otherwise, the eye locations are estimated based on the detected bounding box. - detection_overlap : float
- See
bob.ip.facedetect.detect_single_face()
. - distance : int
- See the Sampling section in the Users Guide of bob.ip.facedetect.
- scale_base : float
- See the Sampling section in the Users Guide of bob.ip.facedetect.
- lowest_scale : float
- See the Sampling section in the Users Guide of bob.ip.facedetect.
- kwargs
- Remaining keyword parameters passed to the
Base
constructor, such ascolor_channel
ordtype
.
-
crop_face
(image, annotations = None) → face[source]¶ Detects the face (and facial landmarks), and used the
face_cropper
given in the constructor to crop the face.Parameters:
- image : 2D or 3D
numpy.ndarray
- The face image to be processed.
- annotations : any
- Ignored.
Returns:
- face : 2D or 3D
numpy.ndarray
(float) - The detected and cropped face.
- image : 2D or 3D
- face_cropper :
-
class
bob.bio.face.preprocessor.
HistogramEqualization
(face_cropper, **kwargs)¶ Bases:
bob.bio.face.preprocessor.Base
Crops the face (if desired) and performs histogram equalization to photometrically enhance the image.
Parameters:
- face_cropper : str or
bob.bio.face.preprocessor.FaceCrop
orbob.bio.face.preprocessor.FaceDetect
orNone
The face image cropper that should be applied to the image. If
None
is selected, no face cropping is performed. Otherwise, the face cropper might be specified as a registered resource, a configuration file, or an instance of a preprocessor.Note
The given class needs to contain a
crop_face
method.- kwargs
- Remaining keyword parameters passed to the
Base
constructor, such ascolor_channel
ordtype
.
-
equalize_histogram
(image) → equalized[source]¶ Performs the histogram equalization on the given image.
Parameters:
- image : 2D
numpy.ndarray
- The image to berform histogram equalization with.
The image will be transformed to type
uint8
before computing the histogram.
Returns:
- equalized : 2D
numpy.ndarray
(float) - The photometrically enhanced image.
- image : 2D
- face_cropper : str or
-
class
bob.bio.face.preprocessor.
INormLBP
(face_cropper, radius=2, is_circular=True, compare_to_average=False, elbp_type='regular', **kwargs)¶ Bases:
bob.bio.face.preprocessor.Base
Performs I-Norm LBP on the given image
-
class
bob.bio.face.preprocessor.
SelfQuotientImage
(face_cropper, sigma=1.4142135623730951, **kwargs)¶ Bases:
bob.bio.face.preprocessor.Base
Crops the face (if desired) and applies self quotient image algorithm [WLW04] to photometrically enhance the image.
Parameters:
- face_cropper : str or
bob.bio.face.preprocessor.FaceCrop
orbob.bio.face.preprocessor.FaceDetect
orNone
The face image cropper that should be applied to the image. If
None
is selected, no face cropping is performed. Otherwise, the face cropper might be specified as a registered resource, a configuration file, or an instance of a preprocessor.Note
The given class needs to contain a
crop_face
method.- sigma : float
- Please refer to the [WLW04] original paper (see
bob.ip.base.SelfQuotientImage
documentation). - kwargs
- Remaining keyword parameters passed to the
Base
constructor, such ascolor_channel
ordtype
.
- face_cropper : str or
-
class
bob.bio.face.preprocessor.
TanTriggs
(face_cropper, gamma=0.2, sigma0=1, sigma1=2, size=5, threshold=10.0, alpha=0.1, **kwargs)¶ Bases:
bob.bio.face.preprocessor.Base
Crops the face (if desired) and applies Tan&Triggs algorithm [TT10] to photometrically enhance the image.
Parameters:
- face_cropper : str or
bob.bio.face.preprocessor.FaceCrop
orbob.bio.face.preprocessor.FaceDetect
orNone
The face image cropper that should be applied to the image. If
None
is selected, no face cropping is performed. Otherwise, the face cropper might be specified as a registered resource, a configuration file, or an instance of a preprocessor.Note
The given class needs to contain a
crop_face
method.- gamma, sigma0, sigma1, size, threshold, alpha
- Please refer to the [TT10] original paper (see
bob.ip.base.TanTriggs
documentation). - kwargs
- Remaining keyword parameters passed to the
Base
constructor, such ascolor_channel
ordtype
.
- face_cropper : str or
Extractors¶
-
class
bob.bio.face.extractor.
DCTBlocks
(block_size=12, block_overlap=11, number_of_dct_coefficients=45, normalize_blocks=True, normalize_dcts=True, auto_reduce_coefficients=False)¶ Bases:
bob.bio.base.extractor.Extractor
Extracts Discrete Cosine Transform (DCT) features from (overlapping) image blocks. These features are based on the
bob.ip.base.DCTFeatures
class. The default parametrization is the one that performed best on the BANCA database in [WMM11].Usually, these features are used in combination with the algorithms defined in bob.bio.gmm. However, you can try to use them with other algorithms.
Parameters:
- block_size : int or (int, int)
- The size of the blocks that will be extracted.
This parameter might be either a single integral value, or a pair
(block_height, block_width)
of integral values. - block_overlap : int or (int, int)
- The overlap of the blocks in vertical and horizontal direction.
This parameter might be either a single integral value, or a pair
(block_overlap_y, block_overlap_x)
of integral values. It needs to be smaller than theblock_size
. - number_of_dct_coefficients : int
- The number of DCT coefficients to use. The actual number will be one less since the first DCT coefficient (which should be 0, if normalization is used) will be removed.
- normalize_blocks : bool
- Normalize the values of the blocks to zero mean and unit standard deviation before extracting DCT coefficients.
- normalize_dcts : bool
- Normalize the values of the DCT components to zero mean and unit standard deviation. Default is
True
.
-
class
bob.bio.face.extractor.
Eigenface
(subspace_dimension)¶ Bases:
bob.bio.base.extractor.Extractor
Performs a principal component analysis (PCA) on the given data.
This algorithm computes a PCA projection (
bob.learn.linear.PCATrainer
) on the given training images, and projects the images into face space. In opposition tobob.bio.base.algorithm.PCA
, here the eigenfces are used as features, i.e., to apply advanced face recognition algorithms on top of them.Parameters:
- subspace_dimension : int or float
- If specified as
int
, defines the number of eigenvectors used in the PCA projection matrix. If specified asfloat
(between 0 and 1), the number of eigenvectors is calculated such that the given percentage of variance is kept. - kwargs :
key=value
pairs - A list of keyword arguments directly passed to the
bob.bio.base.extractor.Extractor
base class constructor.
-
load
(extractor_file)[source]¶ Reads the PCA projection matrix from file.
Parameters:
- extractor_file : str
- An existing file, from which the PCA projection matrix are read.
-
train
(training_images, extractor_file)[source]¶ Generates the PCA covariance matrix and writes it into the given extractor_file.
Beforehand, all images are turned into a 1D pixel vector.
Parameters:
- training_images : [2D
numpy.ndarray
] - A list of 2D training images to train the PCA projection matrix with.
- extractor_file : str
- A writable file, into which the PCA projection matrix (as a
bob.learn.linear.Machine
) will be written.
- training_images : [2D
-
class
bob.bio.face.extractor.
GridGraph
(gabor_directions=8, gabor_scales=5, gabor_sigma=6.283185307179586, gabor_maximum_frequency=1.5707963267948966, gabor_frequency_step=0.7071067811865476, gabor_power_of_k=0, gabor_dc_free=True, normalize_gabor_jets=True, eyes=None, nodes_between_eyes=4, nodes_along_eyes=2, nodes_above_eyes=3, nodes_below_eyes=7, node_distance=None, first_node=None)¶ Bases:
bob.bio.base.extractor.Extractor
Extracts Gabor jets in a grid structure [GHW12] using functionalities from bob.ip.gabor.
The grid can be either aligned to the eye locations (in which case the grid might be rotated), or a fixed grid graph can be extracted.
In the first case, the eye locations in the aligned image need to be provided. Additionally, the number of node between, along, above and below the eyes need to be specified.
In the second case, a regular grid graph is created, by specifying the distance between two nodes. Additionally, the coordinate of the first node can be provided, which otherwise is calculated to evenly fill the whole image with nodes.
Parameters:
- gabor_directions, gabor_scales, gabor_sigma, gabor_maximum_frequency, gabor_frequency_step, gabor_power_of_k, gabor_dc_free
- The parameters of the Gabor wavelet family, with its default values set as given in [WFK97].
Please refer to
bob.ip.gabor.Transform
for the documentation of these values. - normalize_gabor_jets : bool
- Perform Gabor jet normalization during extraction?
- eyes : dict or
None
- If specified, the grid setup will be aligned to the eye positions {‘reye’ : (re_y, re_x), ‘leye’ : (le_y, le_x)}. Otherwise a regular grid graph will be extracted.
- nodes_between_eyes, nodes_along_eyes, nodes_above_eyes, nodes_below_eyes : int
- Only used when
eyes
is notNone
. The number of nodes to be placed between, along, above or below the eyes. The final number of nodes will be: (above + below + 1) times (between + 2*along + 2). - node_distance : (int, int)
- Only used when
eyes
isNone
. The distance between two nodes in the regular grid graph. - first_node : (int, int) or
None
- Only used when
eyes
isNone
. IfNone
, it is calculated automatically to equally cover the whole image.
-
read_feature
(feature_file) → feature[source]¶ Reads the feature written by the
write_feature()
function from the given file.Parameters:
- feature_file : str or
bob.io.base.HDF5File
- The name of the file or the file opened for reading.
Returns:
- feature : [
bob.ip.gabor.Jet
] - The list of Gabor jets read from file.
- feature_file : str or
-
write_feature
(feature, feature_file)[source]¶ Writes the feature extracted by the __call__ function to the given file.
Parameters:
- feature : [
bob.ip.gabor.Jet
] - The list of Gabor jets extracted from the image.
- feature_file : str or
bob.io.base.HDF5File
- The name of the file or the file opened for writing.
- feature : [
-
class
bob.bio.face.extractor.
LGBPHS
(block_size, block_overlap=0, gabor_directions=8, gabor_scales=5, gabor_sigma=6.283185307179586, gabor_maximum_frequency=1.5707963267948966, gabor_frequency_step=0.7071067811865476, gabor_power_of_k=0, gabor_dc_free=True, use_gabor_phases=False, lbp_radius=2, lbp_neighbor_count=8, lbp_uniform=True, lbp_circular=True, lbp_rotation_invariant=False, lbp_compare_to_average=False, lbp_add_average=False, sparse_histogram=False, split_histogram=None)¶ Bases:
bob.bio.base.extractor.Extractor
Extracts Local Gabor Binary Pattern Histogram Sequences (LGBPHS) [ZSG05] from the images, using functionality from bob.ip.base and bob.ip.gabor.
The block size and the overlap of the blocks can be varied, as well as the parameters of the Gabor wavelet (
bob.ip.gabor.Transform
) and the LBP extractor (bob.ip.base.LBP
).Parameters:
- block_size : int or (int, int)
- The size of the blocks that will be extracted.
This parameter might be either a single integral value, or a pair
(block_height, block_width)
of integral values. - block_overlap : int or (int, int)
- The overlap of the blocks in vertical and horizontal direction.
This parameter might be either a single integral value, or a pair
(block_overlap_y, block_overlap_x)
of integral values. It needs to be smaller than theblock_size
. - gabor_directions, gabor_scales, gabor_sigma, gabor_maximum_frequency, gabor_frequency_step, gabor_power_of_k, gabor_dc_free
- The parameters of the Gabor wavelet family, with its default values set as given in [WFK97].
Please refer to
bob.ip.gabor.Transform
for the documentation of these values. - use_gabor_phases : bool
- Extract also the Gabor phases (inline) and not only the absolute values. In this case, Extended LGBPHS features [ZSQ09] will be extracted.
- lbp_radius, lbp_neighbor_count, lbp_uniform, lbp_circular, lbp_rotation_invariant, lbp_compare_to_average, lbp_add_average
The parameters of the LBP. Please see
bob.ip.base.LBP
for the documentation of these values.- sparse_histogram : bool
If specified, the histograms will be handled in a sparse way. This reduces the size of the extracted features, but the computation will take longer.
Note
Sparse histograms are only supported, when
split_histogram = None
.- split_histogram : one of
('blocks', 'wavelets', 'both')
orNone
- Defines, how the histogram sequence is split. This could be interesting, if the histograms should be used in another way as simply concatenating them into a single histogram sequence (the default).
Algorithms¶
-
class
bob.bio.face.algorithm.
GaborJet
(gabor_jet_similarity_type, multiple_feature_scoring='max_jet', gabor_directions=8, gabor_scales=5, gabor_sigma=6.283185307179586, gabor_maximum_frequency=1.5707963267948966, gabor_frequency_step=0.7071067811865476, gabor_power_of_k=0, gabor_dc_free=True)¶ Bases:
bob.bio.base.algorithm.Algorithm
Computes a comparison of lists of Gabor jets using a similarity function of
bob.ip.gabor.Similarity
.The model enrollment simply stores all extracted Gabor jets for all enrollment features. By default (i.e.,
multiple_feature_scoring = 'max_jet'
), the scoring uses an advanced local strategy. For each node, the similarity between the given probe jet and all model jets is computed, and only the highest value is kept. These values are finally averaged over all node positions. Other strategies can be obtained using a differentmultiple_feature_scoring
.Parameters:
- gabor_jet_similarity_type : str:
- The type of Gabor jet similarity to compute.
Please refer to the documentation of
bob.ip.gabor.Similarity
for a list of possible values. - multiple_feature_scoring : str
How to fuse the local similarities into a single similarity value. Possible values are:
'average_model'
: During enrollment, an average model is computed using functionality of bob.ip.gabor.'average'
: For each node, the average similarity is computed. Finally, the average of those similarities is returned.'min_jet', 'max_jet', 'med_jet'
: For each node, the minimum, maximum or median similarity is computed. Finally, the average of those similarities is returned.'min_graph', 'max_graph', 'med_graph'
: For each node, the average similarity is computed. Finally, the minimum, maximum or median of those similarities is returned.
- gabor_directions, gabor_scales, gabor_sigma, gabor_maximum_frequency, gabor_frequency_step, gabor_power_of_k, gabor_dc_free
- These parameters are required by the disparity-based Gabor jet similarity functions, see
bob.ip.gabor.Similarity
.. The default values are identical to the ones in thebob.bio.face.extractor.GridGraph
. Please assure that this class and thebob.bio.face.extractor.GridGraph
class get the same configuration, otherwise unexpected things might happen.
-
enroll
(enroll_features) → model[source]¶ Enrolls the model using one of several strategies. Commonly, the bunch graph strategy [WFK97] is applied, by storing several Gabor jets for each node.
When
multiple_feature_scoring = 'average_model'
, for each node the averagebob.ip.gabor.Jet
is computed. Otherwise, all enrollment jets are stored, grouped by node.Parameters:
- enroll_features : [[
bob.ip.gabor.Jet
]] - The list of enrollment features. Each sub-list contains a full graph.
Returns:
- model : [[
bob.ip.gabor.Jet
]] - The enrolled model.
Each sub-list contains a list of jets, which correspond to the same node.
When
multiple_feature_scoring = 'average_model'
each sub-list contains a singlebob.ip.gabor.Jet
.
- enroll_features : [[
-
read_model
(model_file) → model[source]¶ Reads the model written by the
write_model()
function from the given file.Parameters:
- model_file : str or
bob.io.base.HDF5File
- The name of the file or the file opened for reading.
Returns:
- model : [[
bob.ip.gabor.Jet
]] - The list of Gabor jets read from file.
- model_file : str or
-
score
(model, probe) → score[source]¶ Computes the score of the probe and the model using the desired Gabor jet similarity function and the desired score fusion strategy.
Parameters:
- model : [[
bob.ip.gabor.Jet
]] - The model enrolled by the
enroll()
function. - probe : [
bob.ip.gabor.Jet
] - The probe, e.g., read by the
bob.bio.face.extractor.GridGraph.read_feature()
function.
Returns:
- score : float
- The fused similarity score.
- model : [[
-
score_for_multiple_probes
(model, probes)[source]¶ score(model, probes) -> score
This function computes the score between the given model graph(s) and several given probe graphs. The same local scoring strategy as for several model jets is applied, but this time the local scoring strategy is applied between all graphs from the model and probes.
Parameters:
- model : [[
bob.ip.gabor.Jet
]] - The model enrolled by the
enroll()
function. The sub-lists are groups by nodes. - probes : [[
bob.ip.gabor.Jet
]] - A list of probe graphs. The sub-lists are groups by graph.
Returns:
- score : float
- The fused similarity score.
- model : [[
-
write_model
(model, model_file)[source]¶ Writes the model enrolled by the
enroll()
function to the given file.Parameters:
- model : [[
bob.ip.gabor.Jet
]] - The enrolled model.
- model_file : str or
bob.io.base.HDF5File
- The name of the file or the file opened for writing.
- model : [[
-
class
bob.bio.face.algorithm.
Histogram
(distance_function=<built-in function chi_square>, is_distance_function=True, multiple_probe_scoring='average')¶ Bases:
bob.bio.base.algorithm.Algorithm
Computes the distance between histogram sequences.
Both sparse and non-sparse representations of histograms are supported. For enrollment, to date only the averaging of histograms is implemented.
Parameters:
- distance_function : function
- The function to be used to compare two histograms. This function should accept sparse histograms.
- is_distance_function : bool
- Is the given
distance_function
distance function (lower values are better) or a similarity function (higher values are better)? - multiple_probe_scoring : str or
None
- The way, scores are fused when multiple probes are available.
See
bob.bio.base.score_fusion_strategy()
for possible values.
-
enroll
(enroll_features) → model[source]¶ Enrolls a model by taking the average of all histograms.
- enroll_features : [1D or 2D
numpy.ndarray
] - The histograms that should be averaged. Histograms can be specified sparse (2D) or non-sparse (1D)
Returns:
- model : 1D or 2D
numpy.ndarray
- The averaged histogram, sparse (2D) or non-sparse (1D).
- enroll_features : [1D or 2D
-
score
(model, probe) → score[source]¶ Computes the score of the probe and the model using the desired histogram distance function. The resulting score is the negative distance, if
is_distance_function = True
. Both sparse and non-sparse models and probes are accepted, but their sparseness must agree.Parameters:
- model : 1D or 2D
numpy.ndarray
- The model enrolled by the
enroll()
function. - probe : 1D or 2D
numpy.ndarray
- The probe histograms, which can be specified sparse (2D) or non-sparse (1D)
Returns:
- score : float
- The resulting similarity score.
- model : 1D or 2D