 The zlib/gzip reference implementation allows the user to select from a sliding scale of likely resulting compression-level vs. speed of encoding.Options range from codice_2 (do not attempt compression, just store uncompressed) to codice_9 representing the maximum capability of the reference implementation in zlib/gzip.Other Deflate encoders have been produced, all of which will also produce a compatible bitstream capable of being decompressed by any existing Deflate decoder.