isBlankImage
Function: isBlankImage()
isBlankImage(
imageCanvas,maxLuminance?):boolean
Whether a frame carries no usable signal: no frame decoded yet, page backgrounded, or lens covered. Mean luminance of an 8x8 downscale, so one speck of light does not save a black frame, while a dark but lit scene stays well above the threshold.
Parameters
imageCanvas
HTMLCanvasElement
maxLuminance?
number = 4
Returns
boolean