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  1  1  1  2  2  0  0  2  0  2  2  4  4  1  0  2  1  1  4  1  1  1  2  2  1  1  2  1  0  0  1  2  2  1  0  1  4  2  1  1  1  2  1  1  0  2  1  2  1  2
 0  2  0  2  0  0  2  6  0  0  2  6  4  6  4  6  4  2  0  6  0  0  2  2  0  4  2  6  4  2  0  6  4  4  2  2  2  0  6  2  2  2  4  2  4  2  2  2  2  2  0  6  4  4  4  4  4  0  2  4  0  4  4  2  2  6  0  6  0  4  0  2  0  2  2  0  6  6
 0  0  2  2  0  6  2  0  0  6  2  0  4  2  2  0  6  6  4  0  4  6  6  4  2  4  2  0  2  2  4  4  2  2  0  2  0  6  4  2  6  0  2  6  0  0  6  6  4  6  6  4  6  0  2  2  2  2  4  6  2  2  2  6  2  2  4  4  6  2  4  6  2  2  2  6  2  4
 0  0  0  4  0  0  0  0  0  0  0  0  0  4  0  0  0  0  0  4  4  4  0  0  0  4  0  4  0  0  4  0  4  4  0  4  4  0  4  0  4  4  0  0  0  4  4  4  0  4  4  0  0  4  0  4  0  4  0  4  4  0  0  4  4  4  0  4  4  0  4  4  0  4  0  4  0  0
 0  0  0  0  4  0  0  0  0  0  0  0  0  0  0  0  0  0  4  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  0  4  4  4  0  4  4  0  4  0  4  4  4  0  0  0  0  4  4  0
 0  0  0  0  0  4  0  0  0  0  0  0  0  0  4  0  4  0  0  0  0  4  0  0  4  0  4  4  0  4  4  0  4  4  4  0  0  4  4  4  0  4  0  0  4  0  4  4  4  0  4  0  0  4  4  0  0  4  0  4  0  0  4  0  4  0  0  0  4  4  4  0  0  4  0  4  4  4
 0  0  0  0  0  0  4  0  0  0  0  0  0  0  0  0  0  4  0  0  0  0  0  4  4  4  4  0  4  4  0  0  4  0  4  4  4  0  4  0  4  4  0  0  4  0  4  0  0  0  4  4  4  0  4  4  4  0  4  0  4  4  4  4  4  4  0  4  4  0  0  4  0  0  4  4  0  4
 0  0  0  0  0  0  0  4  0  0  0  4  0  0  4  0  0  0  0  0  0  4  4  0  0  4  0  0  0  4  0  0  4  4  0  4  0  4  0  0  0  4  0  4  0  4  4  0  4  4  0  4  0  4  4  0  4  4  4  0  0  4  4  0  0  4  0  0  4  4  0  4  4  0  0  4  4  0
 0  0  0  0  0  0  0  0  4  0  0  0  0  0  0  4  4  4  4  4  4  0  0  4  0  0  4  4  0  4  0  4  0  4  0  0  4  4  4  0  0  0  4  0  0  4  4  0  0  0  4  4  0  0  0  0  4  4  4  4  0  0  4  4  0  4  0  4  0  4  4  0  0  4  0  4  0  4
 0  0  0  0  0  0  0  0  0  4  0  4  4  4  0  4  0  4  0  0  0  0  4  0  0  0  0  0  4  4  4  4  0  0  4  4  0  4  0  0  4  0  0  0  4  4  4  4  4  0  4  0  0  4  0  4  0  0  4  0  0  0  4  0  4  4  0  4  4  4  4  0  0  0  0  4  0  0
 0  0  0  0  0  0  0  0  0  0  4  0  0  0  0  0  0  0  0  4  4  4  4  4  4  0  0  4  4  0  4  4  4  0  4  4  0  0  0  4  4  0  4  0  0  0  0  4  0  0  4  0  4  4  4  0  4  0  0  4  4  0  4  0  4  0  4  4  0  4  0  0  4  0  4  0  0  0

generates a code of length 78 over Z8 who´s minimum homogenous weight is 64.

Homogenous weight enumerator: w(x)=1x^0+246x^64+294x^66+882x^68+1292x^70+2479x^72+3334x^74+5203x^76+5382x^78+4948x^80+3632x^82+2587x^84+1144x^86+772x^88+254x^90+209x^92+22x^94+61x^96+6x^98+15x^100+5x^104

The gray image is a code over GF(2) with n=312, k=15 and d=128.
This code was found by Heurico 1.16 in 83.9 seconds.