| Extracted from Pike v7.8 release 866 at 2016-04-05.

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Gz

# Method Gz.compress()

Method compress

  `string compress(string data, void|int(0..1) raw, void|int(0..9) level, void|int strategy, void|int(8..15) window_size)`

Description

  Encodes and returns the input data according to the deflate format defined in RFC 1951.

Parameter `data`

  The data to be encoded.

Parameter `raw`

  If set, the data is encoded without the header and footer defined in RFC 1950. Example of uses is the ZIP container format.

Parameter `level`

  Indicates the level of effort spent to make the data compress well. Zero means no packing, 2-3 is considered 'fast', 6 is default and higher is considered 'slow' but gives better packing.

Parameter `strategy`

  The strategy to be used when compressing the data. One of the following.

  `DEFAULT_STRATEGY` | The default strategy as selected in the zlib library.
  `FILTERED` | This strategy is intented for data created by a filter or predictor and will put more emphasis on huffman encoding and less on LZ string matching. This is between DEFAULT_STRATEGY and HUFFMAN_ONLY.
  `RLE` | This strategy is even closer to the HUFFMAN_ONLY in that it only looks at the latest byte in the window, i.e. a window size of 1 byte is sufficient for decompression. This mode is not available in all zlib versions.
  `HUFFMAN_ONLY` | This strategy will turn of string matching completely, only doing huffman encoding. Window size doesn't matter in this mode and the data can be decompressed with a zero size window.
  `FIXED` | In this mode dynamic huffman codes are disabled, allowing for a simpler decoder for special applications. This mode is not available in all zlib versions.

Parameter `window_size`

  Defines the size of the LZ77 window from 256 bytes to 32768 bytes, expressed as 2^x.