Table 2.

PSNR result of (3,4)-threshold proposed scheme by prime p.

p	SHI1	SHI2	SHI3	SHI4	Average
11	44.08	43.92	43.93	43.96	43.97
17	45.39	45.47	45.60	45.39	45.46
19	45.51	45.48	45.50	45.44	45.48
29	45.49	45.38	45.43	45.35	45.41
37	44.15	44.13	44.13	44.04	44.11
79	45.18	45.17	45.03	45.16	45.13
113	45.08	45.11	45.12	45.10	45.10
167	44.15	44.13	44.20	44.15	44.16
251	44.16	44.13	44.16	44.20	44.16