Table 3 Results obtained for the attack problem. Reference refers to a reference feature set of MPEG7 audio features. AF refers to analytical features generated with EDS. Feature sets of smaller dimensions are subsets of the feature sets of dimension 90, constructed using our feature selection algorithm based on AF syntactical structure. Signal refers to the signal used as a feature set, for comparison.

90

75

50

25

15

10

5

3

2

1

[33, 91]

[33, 69]

[31, 37]

[15, 51]

[31, 43]

[20, 91]

[1]

[7, 69]

[12, 16]

[56]

94,5

94

93,3

91,4

91,4

89

89,5

88

80,1

69,2

77.7

76.9

73.3

64.1

64.2

60

59.2

58.1

57.5

44