Figure 15. Effect of parameters on classification performance for the University of Pavia image: (a) effect of
λ
1
, (b) effect of
λ
2
,
(c) effect of the number of training samples, and (d) effect of the patch size.
Figure 16. The sparse-coding coefficients of a testing pixel for different values of
λ
2
: (a)
λ
2
= 0.01, (b)
λ
2
= 0.1, (c)
λ
2
= 1, and (d)
λ
2
= 10.
PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING
September 2019
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