First of all, how good are you at programming? You will have to create your own JPEG decoder because SDK doesnt provide anything, so you have to start from scratch.
Another issue will be reading files - currently you can read external files only from SDCard (look through previous pages where I uploaded my beta file support), if you have experience in programming you will make it useful.
If not... then I suggest you to drop the project before you waste time on something beyond your capabilities (though if you are quick learner you may give it a shot).
I can upload necessary files to start from (though they are already in this topic), but I won't write anything for you. I still regret I dropped my rockchip projects due to lack of time.
It was even more fun to create stuff for rockchip than for any other platform I had experience with.
EDIT:
http://www.mediafire.com/file/0efizw...chip%20SDK.rar