The generator matrix

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

generates a code of length 64 over Z16 who´s minimum homogenous weight is 57.

Homogenous weight enumerator: w(x)=1x^0+148x^57+1096x^58+2420x^59+3920x^60+5712x^61+7234x^62+8104x^63+8862x^64+8148x^65+7062x^66+5452x^67+3580x^68+1992x^69+986x^70+464x^71+220x^72+64x^73+50x^74+8x^75+8x^76+4x^78+1x^80

The gray image is a code over GF(2) with n=512, k=16 and d=228.
This code was found by Heurico 1.16 in 36.9 seconds.