/huffman

Primary LanguageC

huffman-codec

Very simple 8 bits huffman encoder/decoder.

Build

make

Usage

Encoder a file:

./huffman e filename

Output is "out.he"

Decode a file:

./huffman d filename

Output is "out.hd"

例子

james@james-OptiPlex-380:~/huffmantest/test$ hexdump -C 1.txt 00000000 31 0a |1.| 00000002

james@james-OptiPlex-380:~/huffmantest/test$ ../huffman e 1.txt [49:1] R:2 [10:1] value = 10, length = 1 code = 0 value = 49, length = 1 code = 1 File size = 2 Table size = 2

james@james-OptiPlex-380:~/huffmantest/test$ ../huffman d out.he [49:1] R:2 [10:1]

james@james-OptiPlex-380:~/huffmantest/test$ hexdump out.he -C 00000000 48 55 46 46 4d 41 4e 00 02 00 00 00 00 00 00 00 |HUFFMAN.........| 00000010 02 00 00 00 00 00 00 00 0a 01 00 00 00 00 00 00 |................| 00000020 31 01 00 00 00 00 00 00 80 |1........|

编码后的数据包含3部分

文件头

struct huffman_file_header { char magic[8]; uint64_t file_size; uint32_t table_size; };

printf("sizeof(huffman_file_header)=%d\n", sizeof(struct huffman_file_header));

总共24字节长

8字节文件头 8字节文件长度 8字节表格长度（结构体对齐）

huffman表格

表格，每个占用8字节，总共8*表格长度

编码数据区

80 的二进制是 1000 0000 对应 49 10（即十六进制的 31 0a ） */