In this section you can see a table with the existing decoding coding types.
1 Type of code and decode
| Type | Explanation |
| BASE64 | This type implements a BASE 64 character encoder as specified in RFC 1521. This RFC is part of the MIME specification published on the Internet Engineering Task Force (IETF). Unlike others coding schemes, there is nothing in this coding that indicates where a buffer begins or ends. This means that the encoded text begin with the first line of encoded text and end with the last line of encoded text. |
| UC | This type implements a uu of Berkeley character encoder. This encoder became famous for the uuencode program. The basic character encoding is algorithmic, taking 6 bits of binary dates and adding to a ASCII character (space). This converts these six bits into a printable representation. Note that it depends on the ASCII character encoding standard for English. Groups of three bytes are converted into 4 characters by treating the three bytes four groups of 6 bits, group 1 is the most significant byte 1 of six bits, group 2 is the least significant byte 2 two bits plus byte 2 four. In this codification, the prefix of the buffer is begin [mode] [filename]. This is followed for one or more lines of the form: (len) (data) (data) (data)... Where (len) is the number of bytes in this line. It has to be considered that groupings are always four characters, even if the length is not a multiple of three When less than three characters are encoded, the values of the last bytes are undefined and should be ignored. The last line of data in a uuencoded file is represented For a single character space. This is translated by the decoding engine to a line of length zero. This is followed immediately by a line that contains the word 'end [new line]' |
| UU | This class implements a robust character encoder. The encoder is designed to convert binary data into printable characters. The characters are assumed to exist but are not assumed to be ASCII, the whole set is 0-9, A-Z, a-z, "(" and ")". The basic coding unit is a 3-character atom. Encodes two bytes of data. The bytes are encoded in a set of 64 characters, the characters were chosen specifically because they appear in all code sets. It does not matter what the numerical equivalent is because it uses a matrix of characters to assign them. This is like UUencoding with the ASCII dependency removed. The three characters that make up an atom are coded as follows: 00xxxyyy 00axxxxx 00byyyyy 00 = initial zeros, all values are 0 - 63 xxxyyy - Top 3 bits of X, Top 3 bits of Y axxxxx - a = X parity bits, xxxxx 5 lower bits of X byyyyy - b = parity bit Y, yyyyy lower 5 bits of Y. Atoms are arranged in suitable lines for inclusion in an email or file of text. The number of bytes that are coded per line is 48 which keeps the total length of the line less than 80 characters). Each line has the format (DDSS) (DDDD) (DDDD) (DDDD) ... ( CRC). When (xxx) represents an atom of three characters. (LLSS) - 8-bit length (high byte) and sequence number 256 module; (DDDD) - data byte atoms, if the length is odd, (CRC) - 16-bit CRC for the line, include length, sequence and all bytes of data If there is one byte of zero (odd length ) is _NOT_ included in the CRC. |
| default | An encoder to SQL binary transport. |