On-the-fly Segmentation

Although both Block segmentation and Hanning-3 segmentation topologies allow integration of multile segment sizes into a single classifier, the methods may be inadequate to repredsent data in which multiple sub-event resolutions co-exist in a single time-serires. For such cases, we need to consider “On-the-fly Segmentation". There are two possibilities for On-the-fly Segmentation. First, the time-series can be segmented by some kind of segmentation algorithm into spectrally-similar segments of various size [58]. It even be possible to use more than one algorithm, or one algorithm with multiple settings, then consider each segmentation as another branch in the block-segmentation topology (Figure 12.1). So, “On-the-fly Segmentation" is really a special case of block segmentation. The only problem is the varying segment sizes, and how to pose the PDF estimation problem for varying-size segments. One solution to this is to use a segment size independent spectral representation such as autoregressive (AR) or MFCC. We touch on this topic again in Section 14.2.8.