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gzdeflate

(PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)

gzdeflateKomprimiert eine Zeichenkette

Beschreibung

gzdeflate(string $data, int $level = -1, int $encoding = ZLIB_ENCODING_RAW): string|false

Diese Funktion komprimiert die übergebene Zeichenkette mit dem DEFLATE-Datenformat.

Zu Einzelheiten bezüglich des DEFLATE-Kompressions-Algorithmus siehe das Dokument "» DEFLATE Compressed Data Format Specification version 1.3" (RFC 1951).

Parameter-Liste

data

Die zu komprimierenden (deflate == entleeren) Daten.

level

Der Komprimierungsfaktor. Kann von 0 für keine Kompression bis 9 für maximale Kompression übergeben werden. Wird er nicht übergeben, ist der Standard-Komprimierungsfaktor der Standard-Komprimierungsfaktor der zlib-Bibliothek.

encoding

Eine der ZLIB_ENCODING_*-Konstanten.

Rückgabewerte

Die komprimierte (entleerte) Zeichenkette, oder false, wenn ein Fehler auftrat.

Beispiele

Beispiel #1 gzdeflate()-Beispiel

<?php
$compressed
= gzdeflate('Compress me', 9);
echo
$compressed;
?>

Siehe auch

add a note

User Contributed Notes 3 notes

up
49
giunta dot gaetano at sea-aeroportimilano dot it
17 years ago
Take care that that "PHP deflate" != "HTTP deflate".

The deflate encoding used in HTTP is actually zlib encoded.

This is what PHP functions return:
gzencode() == gzip
gzcompress() == zlib (aka. HTTP deflate)
gzdeflate() == *raw* deflate encoding
up
6
anonymous at php dot net
15 years ago
gzcompress produces longer data because it embeds information about the encoding onto the string. If you are compressing data that will only ever be handled on one machine, then you don't need to worry about which of these functions you use. However, if you are passing data compressed with these functions to a different machine you should use gzcompress.
up
0
dmitrysmirnovdeveloper at gmail dot com
6 months ago
this is a benchmark test of gzdeflate (.txt file)
-------------------------------------------------------------------------------------------------------------------
Level ZLIB_ENCODING_RAW ZLIB_ENCODING_DEFLATE ZLIB_ENCODING_GZIP
-------------------------------------------------------------------------------------------------------------------
Level 0 7.22Mb (7574498 bytes) -0.0077% 7.22Mb (7574504 bytes) -0.0077% 7.22Mb (7574516 bytes) -0.0079%
Level 1 2.31Mb (2420570 bytes) 68.0407% 2.31Mb (2420576 bytes) 68.0406% 2.31Mb (2420588 bytes) 68.0405%
Level 2 2.18Mb (2287031 bytes) 69.8039% 2.18Mb (2287037 bytes) 69.8038% 2.18Mb (2287049 bytes) 69.8036%
Level 3 2.11Mb (2216241 bytes) 70.7385% 2.11Mb (2216247 bytes) 70.7384% 2.11Mb (2216259 bytes) 70.7383%
Level 4 2.01Mb (2110510 bytes) 72.1345% 2.01Mb (2110516 bytes) 72.1344% 2.01Mb (2110528 bytes) 72.1343%
Level 5 1.98Mb (2073133 bytes) 72.628% 1.98Mb (2073139 bytes) 72.6279% 1.98Mb (2073151 bytes) 72.6278%
Level 6 1.93Mb (2026592 bytes) 73.2425% 1.93Mb (2026598 bytes) 73.2424% 1.93Mb (2026610 bytes) 73.2423%
Level 7 1.93Mb (2019252 bytes) 73.3394% 1.93Mb (2019258 bytes) 73.3393% 1.93Mb (2019270 bytes) 73.3392%
Level 8 1.92Mb (2018354 bytes) 73.3513% 1.92Mb (2018360 bytes) 73.3512% 1.92Mb (2018372 bytes) 73.351%
Level 9 1.92Mb (2018354 bytes) 73.3513% 1.92Mb (2018360 bytes) 73.3512% 1.92Mb (2018372 bytes) 73.351%
-------------------------------------------------------------------------------------------------------------------
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