Topic Path: Symbol Reference > Files > IdCoderUUE.pas
Contains classes, types, constants, and variables needed to implement coders that use the UUEncode and UUDecode algorithms.
IdCoderUUE.pas contains classes, types, constants, and variables needed to implement coders that use the UUEncode and UUDecode algorithms.
The UUEncode algorithm is designed to encode binary data into a 7-bit textual representation, called UUEncode, as established by UUCP (Unix-to-Unix Copy Program).
UUEncode, like Base64, is an encoding mechanism designed to represent arbitrary sequences of byte data in a form that need not be humanly readable. UUEncode is often used to send EMail attachments in an environment that is not MIME-compliant, and also allows larger files to be divided into multi-part transmissions.
The UUEncode algorithm represents 24-bit groups of input as output strings of 4 encoded characters. Proceeding from left to right, a 24-bit input group is formed by concatenating 3 8-bit input groups. These 24 bits are then treated as 4 concatenated 6-bit groups, each of which is translated into a single digit in the UUEncode alphabet.
UUEncode differs from Base64 encoding by utilizing a different coding table, or alphabet, to represent the encoded output values.
The UUEncode Alphabet can represented by the following encodings and values:
|
Value |
Encoding |
|
0 |
` |
|
1 |
! |
|
2 |
" |
|
3 |
# |
|
4 |
$ |
|
5 |
% |
|
6 |
& |
|
7 |
' |
|
8 |
' |
|
9 |
( |
|
10 |
) |
|
11 |
* |
|
12 |
+ |
|
13 |
, |
|
14 |
- |
|
15 |
. |
|
16 |
/ |
|
17 |
0 |
|
18 |
1 |
|
19 |
2 |
|
20 |
3 |
|
21 |
4 |
|
22 |
5 |
|
23 |
6 |
|
24 |
7 |
|
25 |
8 |
|
26 |
9 |
|
27 |
: |
|
28 |
; |
|
29 |
< |
|
30 |
= |
|
31 |
> |
|
32 |
? |
|
33 |
@ |
|
34 |
A |
|
35 |
B |
|
36 |
C |
|
37 |
D |
|
38 |
E |
|
39 |
F |
|
40 |
G |
|
41 |
H |
|
42 |
I |
|
43 |
J |
|
44 |
K |
|
45 |
L |
|
46 |
M |
|
47 |
N |
|
48 |
O |
|
49 |
P |
|
50 |
Q |
|
51 |
R |
|
52 |
S |
|
53 |
T |
|
54 |
U |
|
55 |
V |
|
56 |
W |
|
57 |
X |
|
58 |
Y |
|
59 |
Z |
|
60 |
[ |
|
61 |
\ |
|
62 |
] |
|
63 |
^ |
|
64 |
_ |
|
Class |
Description |
|
Implements a decoder for data encoded using the UUEncode algorithm and the UUEncode alphabet. | |
|
Implements support for the UUENcode alphabet in the UUEncode algorithm. |
|
Constant |
Description |
|
Represents the valid characters in the UUEncode alphabet. |
|
Variable |
Description |
|
Identifies the decoding table used by TIdDecoderUUE for the UUEncode alphabet. |
|
Copyright © 1993-2006, Chad Z. Hower (aka Kudzu) and the Indy Pit Crew. All rights reserved.
|
|
Post feedback to the Indy Docs Newsgroup.
|
Description