# FaceGesturesModule `hasEyebrowsFrowned` `hasEyebrowsFrowned(face: Face): BoolSignal hasEyebrowsFrowned(face: Face, config: { observationPeriod: ?number, threshold: ?number, backlash: ?number }): BoolSignal` Returns a `BoolSignal` that indicates whether the specified `Face` object has frowned eyebrows. When specified: * `config.threshold` overrides the default threshold; the default value is 1.0. * `config.backlash` overrides the default backlash. Backlash is used to suppress unstable behavior when the eyebrow position is close to threshold. * `config.observationPeriod` sets the period over which median eyebrow positions are tracked, in milliseconds. There is no explicit underlying driver signal for this face gesture. `hasEyebrowsRaised` `hasEyebrowsRaised(face: Face): BoolSignal hasEyebrowsRaised(face: Face, config: { observationPeriod: ?number, threshold: ?number, backlash: ?number }): BoolSignal` Returns a `BoolSignal` that indicates whether the specified `Face` object has raised eyebrows. When specified: * `config.threshold` overrides the default threshold; the default value is 1.0. * `config.backlash` overrides the default backlash. Backlash is used to suppress unstable behavior when the eyebrow position is close to threshold. * `config.observationPeriod` sets the period over which median eyebrow positions are tracked, in milliseconds. There is no explicit underlying driver signal for this face gesture. `hasLeftEyeClosed` `hasLeftEyeClosed(face: Face): BoolSignal hasLeftEyeClosed(face: Face, config: { threshold: ?number, backlash: ?number }): BoolSignal` Returns a `BoolSignal` that indicates whether the specified `Face` object has its left eye open. When specified: * `config.threshold` overrides the default threshold for eye openness. * `config.backlash` sets the default backlash. Backlash is used to minimize state jitter while the openness is near the threshold value. A signal goes ON when `Face.leftEye.openness` reaches `config.threshold` and goes OFF at `config.threshold + config.backlash`. `hasMouthOpen` `hasMouthOpen(face: Face): BoolSignal hasMouthOpen(face: Face, config: { threshold: ?number, backlash: ?number }): BoolSignal` Returns a `BoolSignal` that indicates whether the specified `Face` object has an open mouth. When specified: * `config.threshold` overrides the default threshold for mouth openness. * `config.backlash` overrides the default backlash. Backlash is used to suppress unstable behavior when the mouth openness is close to threshold. A signal goes ON when `Face.mouth.openness` reaches `config.threshold` and goes OFF at `config.threshold - config.backlash`. `hasRightEyeClosed` `hasRightEyeClosed(face: Face): BoolSignal hasRightEyeClosed(face: Face, config: { threshold: ?number, backlash: ?number }): BoolSignal` Returns a `BoolSignal` that indicates whether the specified `Face` object has its right eye open. When specified: * `config.threshold` overrides the default threshold for eye openness. * `config.backlash` sets the default backlash. Backlash is used to minimize state jitter while the openness is near the threshold value. A signal goes ON when `Face.rightEye.openness` reaches `config.threshold` and goes OFF at `config.threshold + config.backlash`. `isHappy` `isHappy(face: Face): BoolSignal` Returns a `BoolSignal` that indicates whether the specified `Face` object is a happy face. `isKissing` `isKissing(face: Face): BoolSignal` Returns a `BoolSignal` that indicates whether the specified `Face` object is a kissing face. `isLeanedBack` `isLeanedBack(face: Face): BoolSignal isLeanedBack(face: Face, config: { angle: ?number, backlash: ?number }): BoolSignal` Returns a `BoolSignal` that indicates whether the specified `Face` object is leaning back. When specified: * `config.angle` overrides the default angular threshold, in radians. * `config.backlash` overrides the default angular backlash, in radians. Backlash is used to suppress unstable behavior when the face rotation is close to threshold. A signal goes ON when angle reaches `config.angle` and goes OFF at `config.angle - config.backlash`. `isLeanedForward` `isLeanedForward(face: Face): BoolSignal isLeanedForward(face: Face, config: { angle: ?number, backlash: ?number }): BoolSignal` Returns a `BoolSignal` that indicates whether the specified `Face` object is leaning forward. When specified: * `config.angle` overrides the default angular threshold, in radians. * `config.backlash` overrides the default angular backlash, in radians. Backlash is used to suppress unstable behavior when the face rotation is close to threshold. A signal goes ON when angle reaches `config.angle` and goes OFF at `config.angle - config.backlash`. `isLeanedLeft` `isLeanedLeft(face: Face): BoolSignal isLeanedLeft(face: Face, config: { angle: ?number, backlash: ?number }): BoolSignal` Returns a `BoolSignal` that indicates whether the specified `Face` object is leaning to the left. When specified: * `config.angle` overrides the default angular threshold, in radians. * `config.backlash` overrides the default angular backlash, in radians. Backlash is used to suppress unstable behavior when the face rotation is close to threshold. A signal goes ON when angle reaches `config.angle` and goes OFF at `config.angle - config.backlash`. `isLeanedRight` `isLeanedRight(face: Face): BoolSignal isLeanedRight(face: Face, config: { angle: ?number, backlash: ?number }): BoolSignal` Returns a `BoolSignal` that indicates whether the specified `Face` object is leaning to the right. When specified: * `config.angle` overrides the default angular threshold, in radians. * `config.backlash` overrides the default angular backlash, in radians. Backlash is used to suppress unstable behavior when the face rotation is close to threshold. A signal goes ON when angle reaches `config.angle` and goes OFF at `config.angle - config.backlash`. `isSmiling` `isSmiling(face: Face): BoolSignal isSmiling(face: Face, config: { lipMix: ?number, threshold: ?number, backlash: ?number }): BoolSignal` Returns a `BoolSignal` that indicates whether the specified face is smiling. A smile is detected when a weighted sum of lip curvatures (`mouth.upperLipCurvature` and `mouth.lowerLipCurvature`) reaches a threshold. When specified: * `config.lipMix` sets the proportion of the upper and lower lip curvatures in the sum. 0.0 is lower lip only, 1.0 is upper lip only. * `config.threshold` overrides the default threshold value for the curvature mix. * `config.backlash` overrides the default backlash. Backlash is used to suppress unstable behavior when the mixed curvature value is close to threshold. A signal goes ON when `mouth.upperLipCurvature * config.lipMix + mouth.lowerLipCurvature * (1 - config.lipMix)` reaches `config.threshold` and goes OFF at `config.threshold - config.backlash`. `isSurprised` `isSurprised(face: Face): BoolSignal` Returns a `BoolSignal` that indicates whether the specified `Face` object is a surprised face. `isTurnedLeft` `isTurnedLeft(face: Face): BoolSignal isTurnedLeft(face: Face, config: { angle: ?number, backlash: ?number }): BoolSignal` Returns a `BoolSignal` that indicates whether the specified `Face` object is turned to the left. When specified: * `config.angle` overrides the default angular threshold, in radians. * `config.backlash` overrides the default angular backlash, in radians. Backlash is used to suppress unstable behavior when the face rotation is close to threshold. A signal goes ON when angle reaches `config.angle` and goes OFF at `config.angle - config.backlash`. `isTurnedRight` `isTurnedRight(face: Face): BoolSignal isTurnedRight(face: Face, config: { angle: ?number, backlash: ?number }): BoolSignal` Returns a `BoolSignal` that indicates whether the specified `Face` object is turned to the right. When specified: * `config.angle` overrides the default angular threshold, in radians. * `config.backlash` overrides the default angular backlash, in radians. Backlash is used to suppress unstable behavior when the face rotation is close to threshold. A signal goes ON when angle reaches `config.angle` and goes OFF at `config.angle - config.backlash`. `onBlink` `onBlink(face: Face): EventSource onBlink(face: Face, config: { threshold: ?number, backlash: ?number }): EventSource` Returns an `EventSource` that fires when both eyes are closed. An eye is considered closed when its `openness` falls below a certain configurable threshold. When specified: * `config.threshold` overrides the default threshold for determining eye openness. * `config.backlash` sets the default backlash. Backlash is used to minimize state jitter while the openness is near the threshold value. `onNod` `onNod(face: Face): EventSource onNod(face: Face, config: { angle: ?number, period: ?number, swings: ?number }): EventSource` Returns an `EventSource` that fires immediately after a face nod is detected. A face nod is a series of consecutive head swing down and up, the first movement is downwards. A swing is detected if the head rotates around the X axis by the specified threshold angle within the specified period of time. The threshold, the period and the number of swings can be configured. When specified: * `config.angle` sets the minimum rotation for one swing, in radians. * `config.period` sets the maximum time limit for one swing, in milliseconds. * `config.swings` sets the count of consecutive alternating swings after which the gesture is detected. `onShake` `onShake(face: Face): EventSource onShake(face: Face, config: { angle: ?number, period: ?number, swings: ?number }): EventSource` Returns an `EventSource` that fires immediately after a face shake is detected. A face shake is a series of consecutive head swings right and left. A swing is detected if the head rotates around the Y axis by the specified threshold angle within the specified period of time. The threshold, the period and the number of swings can be configured. When specified: * `config.angle` sets the minimum rotation for one swing, in radians. * `config.period` sets the maximum time limit for one swing, in milliseconds. * `config.swings` sets the count of consecutive alternating swings after which the gesture is detected.