/////////////////////////////////////////////////////////////////////////////// // /// \file lzma_encoder_presets.c /// \brief Encoder presets // // Author: Lasse Collin // // This file has been put into the public domain. // You can do whatever you want with this file. // /////////////////////////////////////////////////////////////////////////////// #include "common.h" extern LZMA_API(lzma_bool) lzma_lzma_preset(lzma_options_lzma *options, uint32_t preset) { const uint32_t level = preset & LZMA_PRESET_LEVEL_MASK; const uint32_t flags = preset & ~LZMA_PRESET_LEVEL_MASK; const uint32_t supported_flags = LZMA_PRESET_EXTREME; if (level > 9 || (flags & ~supported_flags)) return true; const uint32_t dict_shift = level <= 1 ? 16 : level + 17; options->dict_size = UINT32_C(1) << dict_shift; options->preset_dict = NULL; options->preset_dict_size = 0; options->lc = LZMA_LC_DEFAULT; options->lp = LZMA_LP_DEFAULT; options->pb = LZMA_PB_DEFAULT; options->mode = level <= 2 ? LZMA_MODE_FAST : LZMA_MODE_NORMAL; options->nice_len = level == 0 ? 8 : level <= 5 ? 32 : 64; options->mf = level <= 1 ? LZMA_MF_HC3 : level <= 2 ? LZMA_MF_HC4 : LZMA_MF_BT4; options->depth = 0; if (flags & LZMA_PRESET_EXTREME) { options->lc = 4; // FIXME? options->mode = LZMA_MODE_NORMAL; options->mf = LZMA_MF_BT4; options->nice_len = 273; options->depth = 512; } return false; }