The camera modules(with PIR, PTZ, auto-focus, night-mode) on a 38mm*38mm board were a solved problem at lower cost due to huge volume of IP cameras from China.

The camera modules(with PIR, PTZ, auto-focus, night-mode) on a 38mm*38mm board were a solved problem at lower cost due to huge volume of IP cameras from China. However the code on those modules are fully closed(most running an older version of Linux). RPi's modules are priced reasonably enough to compete against clones from China's vendor, really hard to do, but it did it so far like a magic.