I've solved my problem, I put here the solution, could be interesting for someone seeking for something like this. I wasn't able to find something similar online.
I have updated the animations like this:
/* Animation for the slideshow images */
@-webkit-keyframes imageAnimation {
from {
opacity:0;
}
to {
opacity:1;
}
}
/* Animation for the title */
@-webkit-keyframes titleAnimation {
from {
opacity:0;
}
to {
opacity:1;
-webkit-animation-fill-mode:forwards; }
}
and added an animation fill mode to the elements to force them stay at last animation frame (still visible with opacity:1)
-webkit-animation-fill-mode:forwards;
Here the DEMO