1207753Smm/////////////////////////////////////////////////////////////////////////////// 2207753Smm// 3207753Smm/// \file lzma_encoder_presets.c 4207753Smm/// \brief Encoder presets 5312518Sdelphij/// \note xz needs this even when only decoding is enabled. 6207753Smm// 7207753Smm// Author: Lasse Collin 8207753Smm// 9207753Smm// This file has been put into the public domain. 10207753Smm// You can do whatever you want with this file. 11207753Smm// 12207753Smm/////////////////////////////////////////////////////////////////////////////// 13207753Smm 14207753Smm#include "common.h" 15207753Smm 16207753Smm 17207753Smmextern LZMA_API(lzma_bool) 18207753Smmlzma_lzma_preset(lzma_options_lzma *options, uint32_t preset) 19207753Smm{ 20207753Smm const uint32_t level = preset & LZMA_PRESET_LEVEL_MASK; 21207753Smm const uint32_t flags = preset & ~LZMA_PRESET_LEVEL_MASK; 22207753Smm const uint32_t supported_flags = LZMA_PRESET_EXTREME; 23207753Smm 24207753Smm if (level > 9 || (flags & ~supported_flags)) 25207753Smm return true; 26207753Smm 27207753Smm options->preset_dict = NULL; 28207753Smm options->preset_dict_size = 0; 29207753Smm 30207753Smm options->lc = LZMA_LC_DEFAULT; 31207753Smm options->lp = LZMA_LP_DEFAULT; 32207753Smm options->pb = LZMA_PB_DEFAULT; 33207753Smm 34274261Sdelphij static const uint8_t dict_pow2[] 35274261Sdelphij = { 18, 20, 21, 22, 22, 23, 23, 24, 25, 26 }; 36274261Sdelphij options->dict_size = UINT32_C(1) << dict_pow2[level]; 37207753Smm 38213700Smm if (level <= 3) { 39213700Smm options->mode = LZMA_MODE_FAST; 40213700Smm options->mf = level == 0 ? LZMA_MF_HC3 : LZMA_MF_HC4; 41213700Smm options->nice_len = level <= 1 ? 128 : 273; 42274261Sdelphij static const uint8_t depths[] = { 4, 8, 24, 48 }; 43274261Sdelphij options->depth = depths[level]; 44213700Smm } else { 45213700Smm options->mode = LZMA_MODE_NORMAL; 46213700Smm options->mf = LZMA_MF_BT4; 47213700Smm options->nice_len = level == 4 ? 16 : level == 5 ? 32 : 64; 48213700Smm options->depth = 0; 49213700Smm } 50207753Smm 51207753Smm if (flags & LZMA_PRESET_EXTREME) { 52207753Smm options->mode = LZMA_MODE_NORMAL; 53207753Smm options->mf = LZMA_MF_BT4; 54213700Smm if (level == 3 || level == 5) { 55213700Smm options->nice_len = 192; 56213700Smm options->depth = 0; 57213700Smm } else { 58213700Smm options->nice_len = 273; 59213700Smm options->depth = 512; 60213700Smm } 61207753Smm } 62207753Smm 63207753Smm return false; 64207753Smm} 65