Anomaly recognition method for data streams
First Claim
1. A method of recognising anomalies in data representative of an analogue waveform, the analogue waveform having a plurality of cycles, the data comprising an ordered sequence of data elements, each element having a respective value, the method including the steps of:
- (i) selecting a test group of test elements;
(ii) selecting a comparison group of comparison elements;
(iii) performing a comparison between the test group and the comparison group, the comparison involving the test elements of the test group on the one hand and the comparison elements of the comparison group on the other hand;
(iv) determining as a result of the comparison whether there is a match or a mismatche between the test group and the comparison group;
(v) repeating steps (ii), (iii), and (iv), incrementing the value of a mismatch counter each time a mismatch is found;
(vi) determining an anomaly measure representative of the anomaly of one or more of the test elements, the anomaly measure being dependent on value of the mismatch counter.
1 Assignment
0 Petitions
Accused Products
Abstract
This invention identifies anomalies in a data stream, without prior training, by measuring the difficulty in finding similarities between neighbourhoods in the ordered sequence of elements. Data elements in an area that is similar to much of the rest of the scene score low mismatches. On the other hand a region that possesses many dissimilarities with other parts of the ordered sequence will attract a high score of mismatches. The invention makes use of a trial and error process to find dissimilarities between parts of the data stream and does not require prior knowledge of the nature of the anomalies that may be present. The method avoids the use of processing dependencies between data elements and is capable of a straightforward parallel implementation for each data element. The invention is of application in searching for anomalous patterns in data streams, which include audio signals, health screening and geographical data. A method of error correction is also described.
-
Citations
23 Claims
-
1. A method of recognising anomalies in data representative of an analogue waveform, the analogue waveform having a plurality of cycles, the data comprising an ordered sequence of data elements, each element having a respective value, the method including the steps of:
-
(i) selecting a test group of test elements;
(ii) selecting a comparison group of comparison elements;
(iii) performing a comparison between the test group and the comparison group, the comparison involving the test elements of the test group on the one hand and the comparison elements of the comparison group on the other hand;
(iv) determining as a result of the comparison whether there is a match or a mismatche between the test group and the comparison group;
(v) repeating steps (ii), (iii), and (iv), incrementing the value of a mismatch counter each time a mismatch is found;
(vi) determining an anomaly measure representative of the anomaly of one or more of the test elements, the anomaly measure being dependent on value of the mismatch counter. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21)
-
-
22. A computer program product stored on a computer-usable medium, the computer program product being configured for, in use, recognising anomalies in data representative of an analogue waveform, the analogue waveform having a plurality of cycles, the data comprising an ordered sequence of data elements, each element having a respective value, the computer program product having:
computer-readable program means for selecting a test group of test elements;
computer-readable program means for selecting a comparison group of comparison elements;
computer-readable program means for performing a comparison between the test group and the comparison group, the comparison involving the test elements of the test group on the one hand and the comparison elements of the comparison group on the other hand;
computer-readable program means for determining as a result of the comparison whether there is a match or a mismatches between the test group and the comparison group;
computer-readable program means for determining as a result of the comparison whether there is a match or a mismatches between the test group and the comparison group; and
,computer-readable program means for determining an anomaly measure representative of the anomaly of one or more of the test elements, the anomaly measure being dependent on value of the mismatch counter.
-
23. Apparatus for recognising anomalies in data representative of an analogue waveform, the analogue waveform having a plurality of cycles, the data comprising an ordered sequence of data elements, each elements having a respective value, the apparatus including:
-
means for selecting a test group of test elements;
means for selecting a comparison group of comparison elements;
means for performing a comparison between the test group and the comparison group, the comparison involving the test elements of the test group on the one hand and the comparison elements of the comparison group on the other hand;
means for determining as a result of the comparison whether there is a match or a mismatches between the test group and the comparison group;
means for determining as a result of the comparison whether there is a match or a mismatches between the test group and the comparison group; and
,means for determining an anomaly measure representative of the anomaly of one or more of the test elements, the anomaly measure being dependent on value of the mismatch counter.
-
Specification