인코딩

인코딩 예전에 정리해둔거.

■ UTF-8

- 문자당 1 ~ 4 bytes

- 

Code range            Scalar value                    UTF-8

hexadecimal              binary                    binary Notes 

000000-00007F        0zzzzzzz 0zzzzzzz 

128 codes ASCII equivalence range; byte begins with zero a

seven z seven z 

000080?0007FF

1920 codes 00000yyy yyzzzzzz 110yyyyy 10zzzzzz first byte begins with 110, the following byte begins with 10. 

three y; two y, six z five y; six z 

000800?00FFFF

63488 codes xxxxyyyy yyzzzzzz 1110xxxx 10yyyyyy 10zzzzzz first byte begins with 1110, the following bytes begin with 10. 

four x,four y; two y,six z four x; six y; six z 

010000?10FFFF

1048576 codes 000wwwxx xxxxyyyy yyzzzzzz 11110www 10xxxxxx 10yyyyyy 10zzzzzz First byte begins with 11110, the following bytes begin with 10 

three w, two x; four x, four y; two y, six z three w; six x; six y; six z 

■ UTF-16/UCS-2

- 가변길이 인코딩 for Unicode

- 16bits Word

- surrogates pairs

   - U+FFFF보다 큰 문자 인코딩하기위해서.

"水z??" (water, z, G clef), UTF-16 encoded

 

labeled encoding byte order byte sequence 

UTF-16LE little-endian 34 6C, 7A 00, 34 D8 1E DD 

UTF-16BE big-endian 6C 34, 00 7A, D8 34 DD 1E 

UTF-16 little-endian, with BOM FF FE, 34 6C, 7A 00, 34 D8 1E DD 

UTF-16 big-endian, with BOM FE FF, 6C 34, 00 7A, D8 34 DD 1E 

■ UCS-2

- UTF-16과 거의 흡사하나

- Surrogate pairs 가 없어서, U+FFFF보다 큰문자 지원못함

- 따라서 16bits 고정

- BOM(Bytes Order Mark)에 따라

  Little Endian, Bing Endian 구분.