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5 Recognition results

The Manchester database is described in [4]. There are 300 training images, 10 for each of 30 people. There are 300 normal test images, again 10 for each of 30 people, and there are 90 difficult test images, 3 for each of 30 people.

5.1 Results obtained by Lanitis et al

Recognition rates
Normal test set Difficult test set
Fraction Percentage Fraction Percentage
276/300 92 44/90 48

5.2 Combined templates

Recognition rates
Grid dimension, n Normal test set Difficult test set
Fraction Percentage Fraction Percentage
1 152/300 51 29/90 32
3 236/300 79 49/90 54
5 257/300 86 59/90 66
7 262/300 87 59/90 66
9 271/300 90 61/90 68
11 270/300 90 63/90 70
13 274/300 91 55/90 61
15 267/300 89 55/90 61

5.3 Individual templates

The component templates are applied individually to the difficult test set. The template based on the raw gradient magnitude is also tested. For this comparison, the training images are obtained using combined templates.

Recognition rates - Grid dimension: n=11
Template employed Difficult test set
Fraction Percentage
Ranked grey-levels 53/90 59
Ranked gradient magnitude 47/90 52
X-component of the unit gradient vector 55/90 61
Y-component of the unit gradient vector 42/90 47
Gradient magnitude 21/90 23

5.4 Using a subset of windows for matching

Combined templates are used.

Recognition rates - Grid dimension: n=11
Percentage of Normal test setDifficult test set
windows summed Fraction Percentage Fraction Percentage
100 270/300 90 63/90 70
87.5 283/300 94 65/90 72
75 289/300 96 66/90 73
50 295/300 98 68/90 76
25 289/300 96 69/90 77
12.5 276/300 92 67/90 74

Recognition rates - Grid dimension: n=15
Percentage of Normal test setDifficult test set
windows summed Fraction Percentage Fraction Percentage
100 267/300 89 55/90 61
87.5 274/300 91 56/90 62
75 286/300 95 59/90 66
50 288/300 96 65/90 72
25 288/300 96 72/90 80
12.5 286/300 95 70/90 78


next up previous
Next: 6 Discussion Up: Distinctive Descriptions for Face Previous: 4 Normalisation Results

Hond D A
Fri Jul 11 14:14:48 BST 1997