code: public void encodeTo(QualityFormat format, byte[] buffer, int offset) {
          byte vo = format.getOffset();
          for (int i = 0; i < data.length; ++i)
              buffer[offset++] = (byte) (data[i] + vo);
      }
  
      /**
       * Encodes current quality line with given offset. Common values for offset are 33 and 64.
       *
       * @param offset offset
       * @return bytes encoded quality values
       */
      public byte[] encode(int offset) {
          if (offset < 0 || offset > 70)
              throw new IllegalArgumentException();
  
          byte[] copy = new byte[data.length];
          for (int i = copy.length - 1; i >= 0; --i)
              copy[i] += data[i] + offset;
          return copy;
      }
docs: Encodes current quality line with given offset. Common values for offset are 33 and 64.
  
  @param offset offset
  @return bytes encoded quality values