An Improved NMS-Based Adaptive Edge Detection Method and Its FPGA Implementation

Table 1

3 × 3 Sobel operator.

(a) 0° template

−1	0	1
−2	0	2
−1	0	1

(b) 45° template

0	1	2
−1	0	1
−2	−1	0

(c) 90° template

−1	−2	−1
0	0	0
1	2	1

(d) 135° template

−2	−1	0
−1	0	1
0	1	2

(e) The original grey value