docs: function (pngFile, outputFile) {
          var timelimit = 10 + pngFile.size / 1024,
              iterations = 15,
              splitting = 1;
  
          timelimit = _.min(timelimit, 60);
  
          pngFile.isLarge() && (iterations /= 2);
  
          if (pngFile.isSmall()) {
              iterations *= 2;
              splitting = 3;
          }
  
          // jscs: disable
          var  command = format('%s/zopflipng/zopflipng --lossy_transparent -y --always_zopflify --splitting=%s --iterations=%s --timelimit=%s "%s" "%s"',
                  pwd,
                  splitting,
                  iterations,
                  timelimit,
                  pngFile.name,
                  outputFile.name
              );
  
          return _compress(command, outputFile);
      }