1 /* -*- mode: C; c-basic-offset: 4; indent-tabs-mode: nil -*- */ 2 // vim: expandtab:ts=8:sw=4:softtabstop=4: 3 /////////////////////////////////////////////////////////////////////////////// 4 // 5 /// \file lzma_encoder_presets.c 6 /// \brief Encoder presets 7 // 8 // Author: Lasse Collin 9 // 10 // This file has been put into the public domain. 11 // You can do whatever you want with this file. 12 // 13 /////////////////////////////////////////////////////////////////////////////// 14 15 #include "common.h" 16 17 18 extern LZMA_API(lzma_bool) lzma_lzma_preset(lzma_options_lzma * options,uint32_t preset)19lzma_lzma_preset(lzma_options_lzma *options, uint32_t preset) 20 { 21 const uint32_t level = preset & LZMA_PRESET_LEVEL_MASK; 22 const uint32_t flags = preset & ~LZMA_PRESET_LEVEL_MASK; 23 const uint32_t supported_flags = LZMA_PRESET_EXTREME; 24 25 if (level > 9 || (flags & ~supported_flags)) 26 return true; 27 28 const uint32_t dict_shift = level <= 1 ? 16 : level + 17; 29 options->dict_size = UINT32_C(1) << dict_shift; 30 31 options->preset_dict = NULL; 32 options->preset_dict_size = 0; 33 34 options->lc = LZMA_LC_DEFAULT; 35 options->lp = LZMA_LP_DEFAULT; 36 options->pb = LZMA_PB_DEFAULT; 37 38 options->persistent = false; 39 options->mode = level <= 2 ? LZMA_MODE_FAST : LZMA_MODE_NORMAL; 40 41 options->nice_len = level == 0 ? 8 : level <= 5 ? 32 : 64; 42 options->mf = level <= 1 ? LZMA_MF_HC3 : level <= 2 ? LZMA_MF_HC4 43 : LZMA_MF_BT4; 44 options->depth = 0; 45 46 if (flags & LZMA_PRESET_EXTREME) { 47 options->lc = 4; // FIXME? 48 options->mode = LZMA_MODE_NORMAL; 49 options->mf = LZMA_MF_BT4; 50 options->nice_len = 273; 51 options->depth = 512; 52 } 53 54 return false; 55 } 56