The generator matrix

 1  0  0  1  1  1 14 14  1  1  1  1 10 12  1  1 12  6  4  1  6  1  8  1  1 14  1  1  1  1  1  1  6  1 12  1  8 10  1  1  2  1  1  1 14  1  1  4  8 12  1  1  1  1 12  6  4  1  4  8 12  0  1  1
 0  1  0  0 13  5  1  6 13  1 12 10  1  1 11 10  1  1 10  3  8 15  1 14 11  1  2  0  6  6  1 11  1  9 14 13  1 10  1 10  1 10  2 11  4  3 15  1  1 12  4 15  1 11  1  1  1 11  1  0  1  1 13 10
 0  0  1 11 11  0  3  1  6  1  2 11  6  5  3  8 10  9  1  1  1 12  3  5 10  0 14 11  3 14  5 12 14  7  1 12  2  1  2  5 15  8  9  2  1 13  2 11 11  1 10 12  9  9 14 11  5 13  0  1 12  2 15 10
 0  0  0 12 12  8 12  4  4  8 12  4  0  8 12  0  4 12  4  0  0 12  8 12  8 12 12  0  8  0  4  4  4 12 12  0  8  0  0 12  4 12  8 12 12  0  4 12  4  8  4 12  4 12 12  8  0  8 12  4  4  4  0  4
 0  0  0  0  8  0  8  8  8  0  8  8  8  0  8  0  8  8  8  0  0  8  0  8  0  0  0  8  0  8  0  0  0  0  0  8  8  8  0  0  0  8  8  0  8  8  8  0  8  8  0  0  8  0  0  8  0  8  8  0  8  0  8  8

generates a code of length 64 over Z16 who´s minimum homogenous weight is 58.

Homogenous weight enumerator: w(x)=1x^0+442x^58+1048x^59+2225x^60+2704x^61+3820x^62+4140x^63+4614x^64+3880x^65+3880x^66+2424x^67+1762x^68+936x^69+524x^70+196x^71+84x^72+32x^73+32x^74+17x^76+4x^78+1x^80+2x^82

The gray image is a code over GF(2) with n=512, k=15 and d=232.
This code was found by Heurico 1.16 in 77.1 seconds.