Never used any of these but you could go through and see if they have what you are looking for.
Thanks Ramsey for your response.
I did find this site during my search, however I figure that they would not be useful because they seen to only support GUI interface and did not make any reference to supporting command line operations which is what I need.
I need to automate the conversation process so I can incorporate the command line operations into a script and run it that way.
I did find a limited amount that support this but needed to get some recommendation or input from someone who is already using a pdf conversation software.