Trueface SDK

C++ SDK Modules:

  • General
  • License Validation
  • Input Image
  • Face Detection
  • Face Image Quality
  • 1 to 1 Face Recognition
  • 1 to N Identification
  • Object Detection
  • Spoof Detection
  • Body Pose Estimation
  • Blink Detection
  • Mask Detection
  • Eye glasses Detection
  • Image Annotation

Resources:

  • Environment Variables
  • Frequently Asked Questions
  • Changelog
  • Previous Stable Releases
Trueface SDK
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  • Blink Detection
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Blink Detection¶

ErrorCode Trueface::SDK::detectBlink(const TFImage &tfImage, const FaceBoxAndLandmarks &targetFace, BlinkState &blinkState)¶

Determine if the eyes of the specified face are open or closed. Note, this function does not work well with eyeglasses, which can be detected using Trueface::SDK::detectGlasses.

Parameters
  • tfImage – [in] the input image returned by preprocessImage().

  • targetFace – [in] the face on which to run blink detection.

  • blinkState – [out] the output of the blink prediction.

Returns

error code, see ErrorCode. Note, if the face is not frontal facing, an error will be returned.

struct Trueface::BlinkState¶

Results from blink detection. You can use the members of Trueface::BlinkState to set your own thresholds which work best for your camera and lighting conditions.

Public Members

bool isLeftEyeClosed = false¶

Predicted result for the left eye being closed. Computed as Trueface::BlinkState.leftEyeScore < 0.5.

bool isRightEyeClosed = false¶

Predicted result for the right eye being closed. Computed as Trueface::BlinkState.rightEyeScore < 0.5.

float leftEyeScore = 0.f¶

Score indicating if the left eye is open or closed. 0 indicates closed, 1 indicates open.

float rightEyeScore = 0.f¶

Score indicating if the right eye is open or closed. 0 indicates closed, 1 indicates open.

float leftEyeAspectRatio = 0.f¶

The aspect ratio of the left eye, computed as height / width.

float rightEyeAspectRatio = 0.f¶

The aspect ratio of the right eye, computed as height / width.

To reduce False Positives, blink detection must be run with several constraints:

  • Ensure the face is frontal facing

  • The face should be 1 - 3 ft from the camera

  • Recommended 640 x 480 resolution or better

  • Ensure there is good lighting illuminating the eyes

These constraints are not enforced by the method, and should be enforced by called of SDK for best results.

../_images/blink_detection_distance.png ../_images/blink_detection_lighting.png
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