I once thought the octagon was an international standard for stop signs. Either i'm mistaken or Japan doesn't care about such standards. Either way, this is a Japanese stop sign. Obviously, it says「止まれ」。
Camera model SGH-T999 Shutter speed 1/1,072 Aperture f/2.6 Maximum aperture f/2.8 Exposure bias 0.00 Exposure Aperture priority Exposure index 0.0 Focal length 3.7,mm Distance 0.00 m Light source Unknown Flash Off Metering CenterWeightedAverage Brightness 8.2 ISO sensitivity 80