Video Sensing Block – List

Block	Description
	The Video Sensing Extension is an extension that allows webcams to interact with Projects through Video Sensing.  It activates when the current video motion on the stage is greater than the number entered.
	The Video () on () block is a Sensing block and a Reporter block. It gets values of the video, either motion (on a scale of 1 to 100) or direction (which way the detected motion is going, measured on the same plane as sprite direction), on either the Stage, or the current sprite. If there is no video, the block will return -1. It calculates the values based on “optical flow”.
	The turn video () block is a Video Sensing and a stack block. It turns the webcam on (directly or flipped) or off depending on the argument. Early in the Scratch 2.0 alpha, it was categorized as a looks block before being changed to a sensing block in release and being moved to the Video Sensing Extension in Scratch 3.0.
	The block sets the transparency of the video stream to a certain value.