| 摘要 |
PURPOSE:To prevent a misinformation by stopping the variation detecting action by comparing the current picture with a reference picture during the time a picture- motion sensor is detecting the environmental condition and outputting a signal, and detecting a variation if the environmental condition suits the variation detection apart from an image pickup device. CONSTITUTION:The action of the variation detection of a variation detecting circuit 6 is contorlled by means of a sequence control. For instance, the magnitudes of varia tion of respective picture elements can be obtained sequentially by obtaining the absolute values of the differences between the corresponding picture elements of the preceding picture and the current picture. Such a variation detecting action is executed during the time a picture-associative sensor 44 or a driving device 45 is not operating; if the sensor 44 or the device 45 outputs an operational signal, a variation detection control circuit 7 stops the action of a variation detecting circuit 6, upon ending this stopping, outputs an updating signal to a variation detection reference picture updating circuit 47 to update the picture data in a preceding-picture frame buffer 17 and a background picture frame buffer 46 i.e. the reference picture, and lets the variation detecting circuit 6 restart its detecting action. Therefore, the variation detection is not executed for the environmental variation, hence a misinformation can be prevented from occurring.
|
