chromium/third_party/mediapipe/src/mediapipe/modules/holistic_landmark/face_detection_front_detections_to_roi.pbtxt

# Calculates ROI from detections provided by `face_detection_short_range.tflite`
# model.
type: "FaceDetectionFrontDetectionsToRoi"

# Detected faces. (std::vector<Detection>)
input_stream: "DETECTIONS:detections"
# Image size (width & height). (std::pair<int, int>)
input_stream: "IMAGE_SIZE:image_size"

# Refined (more accurate) ROI to use for face landmarks prediction.
# (NormalizedRect)
output_stream: "ROI:roi"

# Converts the face detection into a rectangle (normalized by image size)
# that encloses the face and is rotated such that the line connecting right side
# of the right eye and left side of the left eye is aligned with the X-axis of
# the rectangle.
node {
  calculator: "DetectionsToRectsCalculator"
  input_stream: "DETECTIONS:detections"
  input_stream: "IMAGE_SIZE:image_size"
  output_stream: "NORM_RECT:raw_roi"
  options: {
    [mediapipe.DetectionsToRectsCalculatorOptions.ext] {
      rotation_vector_start_keypoint_index: 0  # Right eye.
      rotation_vector_end_keypoint_index: 1  # Left eye.
      rotation_vector_target_angle_degrees: 0
      conversion_mode: USE_KEYPOINTS
    }
  }
}

# Expands and shifts the rectangle that contains the face so that it's likely
# to cover the entire face.
node {
  calculator: "RectTransformationCalculator"
  input_stream: "NORM_RECT:raw_roi"
  input_stream: "IMAGE_SIZE:image_size"
  output_stream: "roi"
  options: {
    [mediapipe.RectTransformationCalculatorOptions.ext] {
      scale_x: 2.0
      scale_y: 2.0
      shift_y: -0.1
      square_long: true
    }
  }
}