@Zigurana Thanks for your answer.
I already think to this with a friend and the best solution is the second.
Like it is used in Kodi.
Every one can add and use the media he want like he want without any new coding.
And it use less memory for guys who don't use many media.

But like you write it is harder to code :(
If i found some one who can code the second solution it will be the best.
If not i think i will try to code myself the 1rst easy solution for the moment.
Maybe you have the skill to do it, but for myself i haven't :(