Fundamentals of Sketch-Based Passwords pp 17-33 | Cite as

# Sketch-Based Authentication

## Abstract

This chapter considers two different recognition/matching algorithms, namely dynamic time warping (DTW) and Simple K-Space (SKS). Both algorithms utilize classical pattern recognition techniques to the novel application of sketch-based password. While more sophisticated techniques are possible, DTW and SKS are chosen because the inherent nature of the underlying problem is easily perceived using the approaches. Plus, the fundamental concepts discussed in the chapter generalize beyond the specific algorithmic implementation. The overall sketch-based authentication framework is outlined in this chapter using DTW and SKS. The respective implementation details are rigorously discussed, from which the philosophies are compared and contrasted. In particular, these methods have a similar objective, but different parameterizations, operating spaces, and computational complexities.

## Keywords

DTW SKS Correspondence Density estimation Sketch Authentication## References

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