Not quite, the markings clearly show AC24V / DC12V These devices are frequently just a single diode for half wave rectification and trying to run at 24V DC may possibly cause overheating, leading to failure.It will accept AC or DC anywhere between 12 and 24 volts, to power it.
12V DC or 24V AC, can be either...
Find yourself a 12V DC PSU.
The polarity is clearly marked.Polarity is not marked so it makes no difference which way you connect it.
It may not work if reversing DC due to half wave rectification. Equally it may not matter if bridge rectified and you are if you're using a single local psu... but if a common psu for all cameras it's very important to observe polarity.