Best image encryption algorithm

What is the best algorithm for image encryption that can be coded in matlab?

Answer 1

[Jan]

This depends on what you mean by "best": fastest? minimal memory usage? hardest to decrypt by brute force? smallest implementation? most tolerant to types of input? most compatible to other applications?

You can implement all known encryption methods in Matlab. I prefer AES, see: FEX: CryptAES.

[Walter Roberson]

Minor correction to Jan's answer:

As is the case with most programming languages, MATLAB cannot be used for encryption methods that require true non-determinism. It also cannot be used for encryption methods that require more than 64 bits of address space.

[Jan]

You have even a process limit of 8TB on 64 bit systems, but fortunately you can easily process the encryption in chunks and you do not have to load the complete data to memory at once.

You can import random values from a webservice, which records chaotic systems, e.g. www.random.org as used by Oleg Komarov's and Giampiero Salvi's FEX submissions. Usually this level of non-determinism is enough.

But you are right: If the method is not primitive recursive, you cannot implement it in Matlab. And if you cannot store the data to be encrypted on a computer, you cannot run the method. :-)

[Walter Roberson]

Who said anything about the size of the data? There are encryption methods that require more than 8 TB to process even small data. And clearly an encryption method that requires custom hardware is "better" than an encryption method that can be run on any common computer.

[Jan]

I disagree: If the method need a special hardware, it is "worse".

In my personal opinion, that "best" method encrypts the input to a vector of zeros by using a very specific algorithm. About another at least "very good" method: http://en.wikipedia.org/wiki/Voynich_manuscript