Self-similarity matrix

In data analysis, the self-similarity matrix is a graphical representation of similar sequences in a data series.

Similarity can be explained by different measures, like spatial distance (distance matrix), correlation, or comparison of local histograms or spectral properties (e.g. IXEGRAM{{cite journal|author1= M. A. Casey |author2=A. Westner|title=Separation of mixed audio sources by independent subspace analysis|journal=Proc. Int. Comput. Music Conf|date=July 2000|url=http://www.merl.com/publications/docs/TR2001-31.pdf|accessdate=2013-11-19}}). A similarity plot can be the starting point for dot plots or recurrence plots.

Definition

To construct a self-similarity matrix, one first transforms a data series into an ordered sequence of feature vectors V = (v_1, v_2, \ldots, v_n) , where each vector v_i describes the relevant features of a data series in a given local interval. Then the self-similarity matrix is formed by computing the similarity of pairs of feature vectors

: S(j,k) = s(v_j, v_k) \quad j,k \in (1,\ldots,n)

where s(v_j, v_k) is a function measuring the similarity of the two vectors, for instance, the inner product s(v_j, v_k) = v_j \cdot v_k. Then similar segments of feature vectors will show up as path of high similarity along diagonals of the matrix.{{cite journal|last=Müller|first=Meinard|author2=Michael Clausen |title=Transposition-invariant self-similarity matrices|journal=Proceedings of the 8th International Conference on Music Information Retrieval (ISMIR 2007)|year=2007|pages=47–50|url=http://ismir2007.ismir.net/proceedings/ISMIR2007_p047_mullermuller.pdf|accessdate=2013-11-19}}

Similarity plots are used for action recognition that is invariant to point of view {{cite book

|author1=I.N. Junejo |author2=E. Dexter |author3=I. Laptev |author4=Patrick Pérez |title=Computer Vision – ECCV 2008 |chapter=Cross-View Action Recognition from Temporal Self-similarities |volume=5303 |pages=293–306 | year=2008

| doi=10.1007/978-3-540-88688-4_22

|series=Lecture Notes in Computer Science |isbn=978-3-540-88685-3 |citeseerx=10.1.1.405.1518 }}

and for audio segmentation using spectral clustering of the self-similarity matrix.{{cite journal|last=Dubnov|first=Shlomo|author2=Ted Apel |title=Audio segmentation by singular value clustering|journal=Proceedings of Computer Music Conference (ICMC 2004)|year=2004|citeseerx=10.1.1.324.4298}}

Example

See also

References

{{reflist}}

Further reading

  • {{cite journal

|author1=N. Marwan |author2=M. C. Romano |author3=M. Thiel |author4=J. Kurths | title=Recurrence Plots for the Analysis of Complex Systems

| journal=Physics Reports

| volume=438

| issue=5–6

| year=2007

| doi=10.1016/j.physrep.2006.11.001

| pages=237

| bibcode=2007PhR...438..237M

| arxiv=2501.13933

}}

  • {{cite book

| author=J. Foote

| title=Proceedings of the seventh ACM international conference on Multimedia (Part 1)

| chapter=Visualizing music and audio using self-similarity

| pages=77–80

| year=1999

| doi=10.1145/319463.319472

| isbn=978-1581131512

| citeseerx=10.1.1.223.194

| s2cid=3329298

}}

  • {{cite book

| author=M. A. Casey

| contribution=Sound Classification and Similarity Tools

| publisher=J. Wiley

| year=2002

| pages=309–323

|editor1=B.S. Manjunath |editor2=P. Salembier |editor3=T. Sikora

| title=Introduction to MPEG-7: Multimedia Content Description Language

| isbn=978-0471486787

}}