🚀 go-pugleaf

In article <1992Jul31.153719.28374@ncsu.edu> Webbge@che17.ncsu.EDU (Greg Earl Webb) writes:
>The only problem I can see with this method is how do you insert data
>in a non-regular pattern and still have the ability to remove it later.


I've used one method and have planned at least two others.  I now prefer
#2 for its simplicity.

1.	in one system of mine, I encrypt a vector of length 20 by
	multiplying by a 20x20 matrix.  (Hill's algorithm) Each element of
	the vector is composed of two ASCII characters plus one random bit.

		c0 + 129*(c1 + 129*b)

	(I use 129 so that I can have character 128 which means "end of
	code line") I sometimes end a code line short and just pad the
	remainder with random characters [0..128].

2.	in another system, I prefix compressed data with a fixed number of
	random bytes -- then pass the combination through a transposition
	whose key depends in part on the sum of the bytes of the first
	block of data (code posted here a month or two ago -- c/o
	setzer@math.ncsu.edu (William Setzer).

3.	in another system, I drive a state machine with 3 states (below is
	the stripping machine):

		for ( n = (getc(stdin)) % 17 ;	/* # of bytes of padding */
		      n > 0 ;
		      n-- )
		  getc( stdin ) ;	/* toss the padding */
		for ( n = getc( stdin ); n > 0 ; n-- )
		  use( getc( stdin ) ) ;	/* use good characters */