(PHP 7)
deflate_init — Initialize an incremental deflate context
$encoding
[, array $options
= array()
] )
Initializes an incremental deflate context using the specified
encoding
.
Note that the window option here only sets the window size
of the algorithm, differently from the zlib filters where the same parameter
also sets the encoding to use; the encoding must be set with the
encoding
parameter.
Limitation: there is currently no way to set the header information on a GZIP compressed stream, which are set as follows: GZIP signature (\x1f\x8B); compression method (\x08 == DEFLATE); 6 zero bytes; the operating system set to the current system (\x00 = Windows, \x03 = Unix, etc.)
encoding
One of the ZLIB_ENCODING_*
constants.
options
An associative array which may contain the following elements:
The compression level in range -1..9; defaults to -1.
The compression memory level in range 1..9; defaults to 8.
The zlib window size (logarithmic) in range 8..15; defaults to 15.
One of ZLIB_FILTERED
,
ZLIB_HUFFMAN_ONLY
, ZLIB_RLE
,
ZLIB_FIXED
or
ZLIB_DEFAULT_STRATEGY
(the default).
A string or an array of strings of the preset dictionary (default: no preset dictionary).
Returns a deflate context resource (zlib.deflate) on
success, Im Fehlerfall wird FALSE
zurückgegeben..
If an invalid option is passed to options
or the
context couldn't be created, an error of level E_WARNING
is generated.