In general (if possible to determine) which would make an output harder to turn into plain text with a computer?
- Extreme Length (minor complexity change)
- Extreme algorithmic complexity (minor length change)
(Assuming these are hidden patterns of course)
Possible simple example for length might be a sentence turned numerals by changing to unicode identifier (like
A=0041), this being translated back into words i.e. zero zero four one and for good measure each of those words characters turned back into unicode.
Using example of letter
=0041 =Zerozerofourone =005A00200065002000720020006F0020007A00200065002000720020006F002000660020006F00200075002000720020006F0020006E00200065
So, in this example each character becomes extremely long, and a couple permutations would cause it to become even longer.
I do not have an algorithm to use for an example opposing this, but assuming no difference in character lengths between output and input are the same, but the way in which the character's are encrypted is complex. (not necessarily duplicating, large base of character to choose from, etc.)
I hope this hasn't been too cryptic.