Tweak the compression presets -0 .. -5.
"Extreme" mode might need some further tweaking still. Docs were not updated yet.
This commit is contained in:
parent
77fe5954cd
commit
b4b1cbcb53
|
@ -23,9 +23,6 @@ lzma_lzma_preset(lzma_options_lzma *options, uint32_t preset)
|
||||||
if (level > 9 || (flags & ~supported_flags))
|
if (level > 9 || (flags & ~supported_flags))
|
||||||
return true;
|
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 = NULL;
|
||||||
options->preset_dict_size = 0;
|
options->preset_dict_size = 0;
|
||||||
|
|
||||||
|
@ -33,19 +30,31 @@ lzma_lzma_preset(lzma_options_lzma *options, uint32_t preset)
|
||||||
options->lp = LZMA_LP_DEFAULT;
|
options->lp = LZMA_LP_DEFAULT;
|
||||||
options->pb = LZMA_PB_DEFAULT;
|
options->pb = LZMA_PB_DEFAULT;
|
||||||
|
|
||||||
options->mode = level <= 2 ? LZMA_MODE_FAST : LZMA_MODE_NORMAL;
|
options->dict_size = UINT32_C(1) << (uint8_t []){
|
||||||
|
18, 20, 21, 22, 22, 23, 23, 24, 25, 26 }[level];
|
||||||
|
|
||||||
options->nice_len = level == 0 ? 8 : level <= 5 ? 32 : 64;
|
if (level <= 3) {
|
||||||
options->mf = level <= 1 ? LZMA_MF_HC3 : level <= 2 ? LZMA_MF_HC4
|
options->mode = LZMA_MODE_FAST;
|
||||||
: LZMA_MF_BT4;
|
options->mf = level == 0 ? LZMA_MF_HC3 : LZMA_MF_HC4;
|
||||||
options->depth = 0;
|
options->nice_len = level <= 1 ? 128 : 273;
|
||||||
|
options->depth = (uint8_t []){ 4, 8, 24, 48 }[level];
|
||||||
|
} else {
|
||||||
|
options->mode = LZMA_MODE_NORMAL;
|
||||||
|
options->mf = LZMA_MF_BT4;
|
||||||
|
options->nice_len = level == 4 ? 16 : level == 5 ? 32 : 64;
|
||||||
|
options->depth = 0;
|
||||||
|
}
|
||||||
|
|
||||||
if (flags & LZMA_PRESET_EXTREME) {
|
if (flags & LZMA_PRESET_EXTREME) {
|
||||||
options->lc = 4; // FIXME?
|
options->lc = 4; // FIXME?
|
||||||
options->mode = LZMA_MODE_NORMAL;
|
options->mode = LZMA_MODE_NORMAL;
|
||||||
options->mf = LZMA_MF_BT4;
|
options->mf = LZMA_MF_BT4;
|
||||||
options->nice_len = 273;
|
if (level == 3 || level == 5) {
|
||||||
options->depth = 512;
|
options->nice_len = 192;
|
||||||
|
} else {
|
||||||
|
options->nice_len = 273;
|
||||||
|
options->depth = 512;
|
||||||
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
return false;
|
return false;
|
||||||
|
|
Loading…
Reference in New Issue