Substituto de subgrupo sed substitua
sed -E "s/(.*)\.png/\/full\/path\/\1/g" <<< "lolsed_bulsh.png"
# output is
# /full/path/lolsed_bulsh
Wandering Worm
sed -E "s/(.*)\.png/\/full\/path\/\1/g" <<< "lolsed_bulsh.png"
# output is
# /full/path/lolsed_bulsh