Research Article

Research on High-Frequency Combination Coding-Based SSVEP-BCIs and Its Signal Processing Algorithms

Figure 5

The boundary prediction method. ■—endpoint; ●—1 order approximate point: the intersection of the vertical axis and the curve, that is, straight line continuation of two extreme value points near the end; ▲—the last extreme value that is obtained through the boundary prediction method; the formula of extreme value is as follows through boundary prediction method: .
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