pixelWatcher
A library that makes it easy to monitor changes in RGB values within some region of an HTML5 canvas or video object. Is especially handy for aiding in motion detection and dynamic labeling so that dom elements overlaying a video background aren't camouflaged.
PixelWatcher emits two event types named "pixelstats" and "motion." pixelStats fires at your chosen framerate with data in e.details of the form {r: int, g: int, b: int, avg: int} where r, g, and b are the average color values over a monitored region and avg is the total avg. Motion events fire when a significant change in the pixel averages is detected from one frame to the next.
install
bower install pixelWatcher
PixelWatcher Options
videoObject: An html5 video or canvas element
frameRate: Sampling rate, defaults to 4 fps
width: Width of the area you'd like to sample for color changes
height: Height of the area you'd like to sample for color changes
offsetX: x-offset of the area you'd like to sample for color changes
offsetY: y-offset of the area you'd like to sample for color changes
motionThreshold: determines the sensitivity of motion detection. Higher values are less sensitive (default: 1)
