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comparison pytouhou/utils/lzss.pyx @ 367:2674c789e0c3

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Various optimizations
author Thibaut Girka <thib@sitedethib.com>
date Tue, 10 Jul 2012 00:25:08 +0200
parents b5c7369abd7c
children 71cd4461bb7f
comparison
equal deleted inserted replaced
366:7dc012f631dc 367:2674c789e0c3
20 unsigned int dictionary_size=0x2000, 20 unsigned int dictionary_size=0x2000,
21 unsigned int offset_size=13, 21 unsigned int offset_size=13,
22 unsigned int length_size=4, 22 unsigned int length_size=4,
23 unsigned int minimum_match_length=3): 23 unsigned int minimum_match_length=3):
24 cdef unsigned int i, ptr, dictionary_head, offset, length 24 cdef unsigned int i, ptr, dictionary_head, offset, length
25 cdef unsigned char flag, byte, *out_data, *dictionary 25 cdef unsigned char byte, *out_data, *dictionary
26 cdef bytes _out_data 26 cdef bytes _out_data
27 27
28 out_data = <unsigned char*> malloc(size) 28 out_data = <unsigned char*> malloc(size)
29 dictionary = <unsigned char*> calloc(dictionary_size, 1) 29 dictionary = <unsigned char*> calloc(dictionary_size, 1)
30 dictionary_head, ptr = 1, 0 30 dictionary_head, ptr = 1, 0
31 31
32 while ptr < size: 32 while ptr < size:
33 flag = bitstream.read_bit() 33 if bitstream.read_bit():
34 if flag:
35 # The `flag` bit is set, indicating the upcoming chunk of data is a literal 34 # The `flag` bit is set, indicating the upcoming chunk of data is a literal
36 # Add it to the uncompressed file, and store it in the dictionary 35 # Add it to the uncompressed file, and store it in the dictionary
37 byte = bitstream.read(8) 36 byte = bitstream.read(8)
38 dictionary[dictionary_head] = byte 37 dictionary[dictionary_head] = byte
39 dictionary_head = (dictionary_head + 1) % dictionary_size 38 dictionary_head = (dictionary_head + 1) % dictionary_size