## Mathematica, <s>178</s> <s>134</s> 132 bytes ##

    ""<>Table[(f/@{##2})[[x[[i]],i]],{i,Length@(x=(f=Characters)@#2/.Table[ToString@i->2+Floor[#/2^(7-i)]~Mod~2,{i,0,7}]/._String->1)}]&