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1 /* LzmaLib.h -- LZMA library interface | |
2 2008-08-05 | |
3 Igor Pavlov | |
4 Public domain */ | |
5 | |
6 #ifndef __LZMALIB_H | |
7 #define __LZMALIB_H | |
8 | |
9 #include "Types.h" | |
10 | |
11 #ifdef __cplusplus | |
12 #define MY_EXTERN_C extern "C" | |
13 #else | |
14 #define MY_EXTERN_C extern | |
15 #endif | |
16 | |
17 #define MY_STDAPI MY_EXTERN_C int MY_STD_CALL | |
18 | |
19 #define LZMA_PROPS_SIZE 5 | |
20 | |
21 /* | |
22 RAM requirements for LZMA: | |
23 for compression: (dictSize * 11.5 + 6 MB) + state_size | |
24 for decompression: dictSize + state_size | |
25 state_size = (4 + (1.5 << (lc + lp))) KB | |
26 by default (lc=3, lp=0), state_size = 16 KB. | |
27 | |
28 LZMA properties (5 bytes) format | |
29 Offset Size Description | |
30 0 1 lc, lp and pb in encoded form. | |
31 1 4 dictSize (little endian). | |
32 */ | |
33 | |
34 /* | |
35 LzmaCompress | |
36 ------------ | |
37 | |
38 outPropsSize - | |
39 In: the pointer to the size of outProps buffer; *outPropsSize = LZMA_PROPS
_SIZE = 5. | |
40 Out: the pointer to the size of written properties in outProps buffer; *out
PropsSize = LZMA_PROPS_SIZE = 5. | |
41 | |
42 LZMA Encoder will use defult values for any parameter, if it is | |
43 -1 for any from: level, loc, lp, pb, fb, numThreads | |
44 0 for dictSize | |
45 | |
46 level - compression level: 0 <= level <= 9; | |
47 | |
48 level dictSize algo fb | |
49 0: 16 KB 0 32 | |
50 1: 64 KB 0 32 | |
51 2: 256 KB 0 32 | |
52 3: 1 MB 0 32 | |
53 4: 4 MB 0 32 | |
54 5: 16 MB 1 32 | |
55 6: 32 MB 1 32 | |
56 7+: 64 MB 1 64 | |
57 | |
58 The default value for "level" is 5. | |
59 | |
60 algo = 0 means fast method | |
61 algo = 1 means normal method | |
62 | |
63 dictSize - The dictionary size in bytes. The maximum value is | |
64 128 MB = (1 << 27) bytes for 32-bit version | |
65 1 GB = (1 << 30) bytes for 64-bit version | |
66 The default value is 16 MB = (1 << 24) bytes. | |
67 It's recommended to use the dictionary that is larger than 4 KB and | |
68 that can be calculated as (1 << N) or (3 << N) sizes. | |
69 | |
70 lc - The number of literal context bits (high bits of previous literal). | |
71 It can be in the range from 0 to 8. The default value is 3. | |
72 Sometimes lc=4 gives the gain for big files. | |
73 | |
74 lp - The number of literal pos bits (low bits of current position for literals). | |
75 It can be in the range from 0 to 4. The default value is 0. | |
76 The lp switch is intended for periodical data when the period is equal to 2
^lp. | |
77 For example, for 32-bit (4 bytes) periodical data you can use lp=2. Often i
t's | |
78 better to set lc=0, if you change lp switch. | |
79 | |
80 pb - The number of pos bits (low bits of current position). | |
81 It can be in the range from 0 to 4. The default value is 2. | |
82 The pb switch is intended for periodical data when the period is equal 2^pb
. | |
83 | |
84 fb - Word size (the number of fast bytes). | |
85 It can be in the range from 5 to 273. The default value is 32. | |
86 Usually, a big number gives a little bit better compression ratio and | |
87 slower compression process. | |
88 | |
89 numThreads - The number of thereads. 1 or 2. The default value is 2. | |
90 Fast mode (algo = 0) can use only 1 thread. | |
91 | |
92 Out: | |
93 destLen - processed output size | |
94 Returns: | |
95 SZ_OK - OK | |
96 SZ_ERROR_MEM - Memory allocation error | |
97 SZ_ERROR_PARAM - Incorrect paramater | |
98 SZ_ERROR_OUTPUT_EOF - output buffer overflow | |
99 SZ_ERROR_THREAD - errors in multithreading functions (only for Mt version) | |
100 */ | |
101 | |
102 MY_STDAPI LzmaCompress(unsigned char *dest, size_t *destLen, const unsigned char
*src, size_t srcLen, | |
103 unsigned char *outProps, size_t *outPropsSize, /* *outPropsSize must be = 5 */ | |
104 int level, /* 0 <= level <= 9, default = 5 */ | |
105 unsigned dictSize, /* default = (1 << 24) */ | |
106 int lc, /* 0 <= lc <= 8, default = 3 */ | |
107 int lp, /* 0 <= lp <= 4, default = 0 */ | |
108 int pb, /* 0 <= pb <= 4, default = 2 */ | |
109 int fb, /* 5 <= fb <= 273, default = 32 */ | |
110 int numThreads /* 1 or 2, default = 2 */ | |
111 ); | |
112 | |
113 /* | |
114 LzmaUncompress | |
115 -------------- | |
116 In: | |
117 dest - output data | |
118 destLen - output data size | |
119 src - input data | |
120 srcLen - input data size | |
121 Out: | |
122 destLen - processed output size | |
123 srcLen - processed input size | |
124 Returns: | |
125 SZ_OK - OK | |
126 SZ_ERROR_DATA - Data error | |
127 SZ_ERROR_MEM - Memory allocation arror | |
128 SZ_ERROR_UNSUPPORTED - Unsupported properties | |
129 SZ_ERROR_INPUT_EOF - it needs more bytes in input buffer (src) | |
130 */ | |
131 | |
132 MY_STDAPI LzmaUncompress(unsigned char *dest, size_t *destLen, const unsigned ch
ar *src, SizeT *srcLen, | |
133 const unsigned char *props, size_t propsSize); | |
134 | |
135 #endif | |
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