I already googled a lot and mostly read that importing composite Signal to the Raspberry is almost impossible. I would just take a webcam and proceed since it seems to be a lot easier.
The problem is, I already have this camera and just wanted to know if there is absolutely no way to get that NTSC-signal on the Raspberry (perhaps by connecting it directly to some pins?).
If not, I will just get a webcam as I said, but I wanted to check that before I can admit that the investment in the TTL Camera was useless.