The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  2  1  1  1  8  1  1  1  1  1  1  1  1  1  2  1  1  1  4  0  1  2  8  1  1  1  2  1  8  1  1  1  1  2  2  2
 0  2  0  6  4 14 12  2  0  6 12 10  8 14  4  2  0 10  4 14  8  2 14  4  0 12 10 14 14  0 14 10  2  4 14  0  6  8  2  2  0 12  6  2 12  6  2  2 14  2  2  2 10 12 10  8  2 10 14  4  8 14  0  6
 0  0 12  0  4  4  8  4  0  8  0  0  4  4  4 12  8  0  8  0 12  4 12  4  4  4 12 12 12  8  8  0 12  0  4  4 12 12  4  8 12  4  0  0  8  4 12  8  4  4  4  4 12  8  0  4  4  8  4  8 12 12 12  0
 0  0  0  8  0  0  8  0  0  8  8  0  0  0  0  0  0  0  8  8  8  8  8  8  8  8  8  8  8  0  8  0  8  8  8  0  0  8  8  8  8  8  0  8  0  0  8  8  8  0  0  8  0  0  0  0  0  8  8  0  8  8  8  8
 0  0  0  0  8  0  0  8  8  8  8  8  0  0  8  8  8  0  0  8  8  0  0  8  0  0  8  8  0  0  0  8  8  8  0  8  8  8  8  0  0  8  8  8  8  8  0  8  8  8  8  0  8  8  8  8  8  0  8  0  0  8  8  8
 0  0  0  0  0  8  0  8  0  0  0  0  8  0  8  0  8  8  8  8  0  0  8  8  0  8  8  0  8  8  8  8  0  8  8  0  0  8  0  8  0  0  0  0  0  8  0  0  8  8  0  8  8  8  8  8  8  0  0  8  0  0  0  8

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

Homogenous weight enumerator: w(x)=1x^0+103x^58+92x^59+266x^60+244x^61+497x^62+584x^63+641x^64+520x^65+454x^66+268x^67+212x^68+68x^69+86x^70+16x^71+19x^72+11x^74+10x^76+1x^78+2x^80+1x^104

The gray image is a code over GF(2) with n=512, k=12 and d=232.
This code was found by Heurico 1.16 in 0.72 seconds.