Face Detection and Modeling for Recognition - Biometrics Research ...
Face Detection and Modeling for Recognition - Biometrics Research ...
Face Detection and Modeling for Recognition - Biometrics Research ...
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2.6 A breakdown of face recognition algorithms based on the pose-dependency,<br />
face representation, <strong>and</strong> features used in matching. . . . . . . . . . . 45<br />
2.7 <strong>Face</strong> modeling using anthropometric measurements (downloaded<br />
from [35]): (a) anthropometric measurements; (b) a B-spline face model. 48<br />
2.8 Generic face models: (a) Water’s animation model; (b) anthropometric<br />
measurements; (b) six kinds of face models <strong>for</strong> representing general<br />
facial geometry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49<br />
3.1 <strong>Face</strong> detection algorithm. The face localization module finds face c<strong>and</strong>idates,<br />
which are verified by the detection module based on facial<br />
features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60<br />
3.2 Skin detection: (a) a yellow-biased face image; (b) a lighting compensated<br />
image; (c) skin regions of (a) shown in white; (d) skin regions of (b). . 62<br />
3.3 The Y C b C r color space (blue dots represent the reproducible color on<br />
a monitor) <strong>and</strong> the skin tone model (red dots represent skin color<br />
samples). (a) The Y C b C r space; (b) a 2D projection in the C b -C r<br />
subspace; (c) a 2D projection in the (C b /Y )-(C r /Y ) subspace. . . . . 65<br />
3.4 The dependency of skin tone color on luma. The skin tone cluster (red<br />
dots) is shown in (a) the rgY , (c) the CIE xyY , <strong>and</strong> (e) the HSV color<br />
spaces; the 2D projection of the cluster is shown in (b) the r − g, (d)<br />
the x−y , <strong>and</strong> (f) S −H color subspaces, where blue dots represent the<br />
reproducible color on a monitor. For a better presentation of cluster<br />
shape, we normalize the luma Y in the rgY <strong>and</strong> the CIE xyY by 255,<br />
<strong>and</strong> swap the hue <strong>and</strong> saturation coordinates in the HSV space. The<br />
skin tone cluster is less compact at low saturation values in (e) <strong>and</strong> (f). 66<br />
3.5 2D projections of the 3D skin tone cluster in (a) the Y -C b subspace; (b)<br />
the Y -C r subspace. Red dots indicate the skin cluster. Three blue<br />
dashed curves, one <strong>for</strong> cluster center <strong>and</strong> two <strong>for</strong> boundaries, indicate<br />
the fitted models. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67<br />
3.6 The nonlinear trans<strong>for</strong>mation of the Y C b C r color space. (a) The trans<strong>for</strong>med<br />
Y C b C r color space; (b) a 2D projection of (a) in the C b -C r<br />
subspace, in which the elliptical skin model is overlaid on the skin<br />
cluster. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67<br />
3.7 Nonlinear color trans<strong>for</strong>m. Six detection examples, with <strong>and</strong> without the<br />
trans<strong>for</strong>m are shown. For each example, the images shown in the first<br />
column are skin regions <strong>and</strong> detections without the trans<strong>for</strong>m, while<br />
those in the second column are results with the trans<strong>for</strong>m. . . . . . . 68<br />
3.8 Construction of the face mask. (a) <strong>Face</strong> c<strong>and</strong>idates; (b) one of the face<br />
c<strong>and</strong>idates; (c) grouped skin areas; (d) the face mask. . . . . . . . . . 69<br />
3.9 Construction of eye maps: (a) from chroma; (b) from luma; (c) the combined<br />
eye map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71<br />
3.10 An example of a hemispheric structuring element <strong>for</strong> grayscale morphological<br />
dilation <strong>and</strong> erosion with σ = 1. . . . . . . . . . . . . . . . . . 72<br />
3.11 Construction of the mouth map. . . . . . . . . . . . . . . . . . . . . . . . 74<br />
3.12 Computation of face boundary <strong>and</strong> the eye-mouth triangle. . . . . . . . . 77<br />
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