<?php namespace PhpZip\Constants; /** * Compression levels for Deflate and BZIP2. * * {@see https://pkware.cachefly.net/webdocs/casestudies/APPNOTE.TXT} Section 4.4.4: * * For Methods 8 and 9 - Deflating * ------------------------------- * Bit 2 Bit 1 * 0 0 Normal (-en) compression option was used. * 0 1 Maximum (-exx/-ex) compression option was used. * 1 0 Fast (-ef) compression option was used. * 1 1 Super Fast (-es) compression option was used. * * Different programs encode compression level information in different ways: * * Deflate Compress Level pkzip zip 7z, WinRAR WinZip * ---------------------- ---------------- ------- ---------- ------ * Super Fast compression 1 1 * Fast compression 2 1, 2 * Normal Compression 3 - 8 (5 default) 3 - 7 1 - 9 * Maximum compression 9 8, 9 9 */ interface ZipCompressionLevel { /** @var int Compression level for super fast compression. */ const SUPER_FAST = 1; /** @var int compression level for fast compression */ const FAST = 2; /** @var int compression level for normal compression */ const NORMAL = 5; /** @var int compression level for maximum compression */ const MAXIMUM = 9; /** * @var int int Minimum compression level * * @internal */ const LEVEL_MIN = self::SUPER_FAST; /** * @var int int Maximum compression level * * @internal */ const LEVEL_MAX = self::MAXIMUM; }