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bzcompress

PHP function Edit on GitHub ✎

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

Compress a string into bzip2 encoded data

Description

bzcompress(string $data, int $block_size = 4, int $work_factor = 0): string|int

bzcompress() compresses the given string and returns it as bzip2 encoded data.

Parameters

data

The string to compress.

block_size

Specifies the blocksize used during compression and should be a number from 1 to 9 with 9 giving the best compression, but using more resources to do so.

work_factor

Controls how the compression phase behaves when presented with worst case, highly repetitive, input data. The value can be between 0 and 250 with 0 being a special case.

Regardless of the work_factor, the generated output is the same.

Return Values

The compressed string, or an error number if an error occurred.

Errors/Exceptions

As of PHP 8.5.0, a ValueError is thrown if block_size is not between 1 and 9, or if work_factor is not between 0 and 250.

Changelog

Version	Description
8.5.0	A `ValueError` is now thrown if `block_size` is not between 1 and 9, or if `work_factor` is not between 0 and 250.

Examples

Compressing data

php

<?php
$str = "sample data";
$bzstr = bzcompress($str, 9);
echo $bzstr;
?>