I am looking for a word that describes both of these activities, however the word coding does not seem to be suitable.
Likewise with encryption and decryption, cryption does not work well.
is the study of encryption and decryption.
is software/hardware that does both encoding and decoding.
Encode means : "To translate information into code" Decode means : "To translate code into information"
Therefore translate would be used to describe them both.
Since translate may seem vague I would suggest some synonyms: transcribe, transpose, or convert.
Would transcoding be suitable in your context ?
How about pure and simple “processing”?
Why does everyone and OP have a problem with "coding". This is the correct term for encoding and decoding. For example, see http://en.wikipedia.org/wiki/Coding_theory
Not sure about this, but would "convert" work?