el path me lo pasaron es usr/bin/mogrify
Código PHP:
$command= "convert -geometry 300x300 '" .$destino. "' ../img_productos/res_".$max_id.".jpg";
exec(. $command);
$command= "convert convert -bordercolor Black -border 2x2 ../img_productos/res_".$max_id.".jpg ../img_productos/res_".$max_id.".jpg";
exec(. $command);
$command= "convert -geometry 80x80 '" .$destino. "' ../img_productos/tum_".$max_id.".jpg";
exec(. $command);
$command= "convert convert -bordercolor Black -border 2x2 ../img_productos/tum_".$max_id.".jpg ../img_productos/tum_".$max_id.".jpg";
exec(. $command);