Update README.md

README.md

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 # steganoCode
 Steganography in source code
+
+```
+usage: stego.py [-h] [--input INPUT] [--output OUTPUT] [--stdin] [--stdout] [--hide] [--showSource] [--showFound]
+                [--lang LANG] [--message MESSAGE] [--comment COMMENT]
+
+optional arguments:
+  -h, --help         show this help message and exit
+  --input INPUT      Input file
+  --output OUTPUT    Output file
+  --stdin            Read from stdin
+  --stdout           Output to stdout
+  --hide             Hide Mode
+  --showSource       Show clean source
+  --showFound        Show Matches
+  --lang LANG        Programming Language
+  --message MESSAGE  Hidden message
+  --comment COMMENT  Comment
+
+```
+
+This tools encodes secret messages in a comment, which is appended at the start of the output
+
+
+## Encoding:
+
+The message is first commuted from unicode to binary and then to a sequence of these two invisible unicode characters:
+* `U+200F RIGHT-TO-LEFT MARK` for binary digit `1`
+* `U+200E LEFT-TO-RIGHT MARK` fot binary digit `0`
+
+The last char in the sequence is always ignored in decoding and is `U+200F RIGHT-TO-LEFT MARK` (to restore the correct reading order that the previous char would impart)
+A comment is created, accounting for the programming language and placed at the top of the output.
+The comment contains the message payload followed optionally by a text comment
+
+## Decoding
+
+Every sequence of the two designated chars is stored and decoded.
+
+if `showSource` is enabled, then the source output contains the original message in the comments where it appears
+if `showFound` is enabled, the output contains all the decoded instances
+
+
+### example
+[![asciicast](https://asciinema.org/a/eNpUFJp7b3q68Bwx0x1Ak0E0j.svg)](https://asciinema.org/a/eNpUFJp7b3q68Bwx0x1Ak0E0j)