mp.tasks.vision.FaceLandmarker

Class that performs face landmark detection on images.

mp.tasks.vision.FaceLandmarker(
    lib: mp.tasks.vision.drawing_styles.face_landmarker.serial_dispatcher.SerialDispatcher,
    handle: ctypes.c_void_p,
    dispatcher: mp.tasks.vision.drawing_styles.face_landmarker.async_result_dispatcher.AsyncResultDispatcher,
    async_callback: _C_TYPES_RESULT_CALLBACK
)

lib The dispatch library to use for the face landmarker.
handle The C pointer to the face landmarker.
dispatcher The async result handler for the face landmarker.
async_callback The c callback for the face landmarker.

Methods

close

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close()

Closes the FaceLandmarker.

create_from_model_path

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@classmethod
create_from_model_path(
    model_path: str
) -> 'FaceLandmarker'

Creates an FaceLandmarker object from a TensorFlow Lite model and the default FaceLandmarkerOptions.

Note that the created FaceLandmarker instance is in image mode, for detecting face landmarks on single image inputs.

Args
model_path Path to the model.

Returns
FaceLandmarker object that's created from the model file and the default FaceLandmarkerOptions.

Raises
ValueError If failed to create FaceLandmarker object from the provided file such as invalid file path.
RuntimeError If other types of error occurred.

create_from_options

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@classmethod
create_from_options(
    options: mp.tasks.vision.FaceLandmarkerOptions
) -> 'FaceLandmarker'

Creates the FaceLandmarker object from face landmarker options.

Args
options Options for the face landmarker task.

Returns
FaceLandmarker object that's created from options.

Raises
ValueError If failed to create FaceLandmarker object from FaceLandmarkerOptions such as missing the model.
RuntimeError If other types of error occurred.

detect

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detect(
    image: mp.Image,
    image_processing_options: Optional[mp.tasks.vision.ImageProcessingOptions] = None
) -> mp.tasks.vision.FaceLandmarkerResult

Performs face landmark detection on the provided MediaPipe Image.

Only use this method when the FaceLandmarker is created with the image running mode.

Args
image MediaPipe Image.
image_processing_options Options for image processing.

Returns
A face landmarker result object that contains a list of face landmarks.

Raises
ValueError If any of the input arguments is invalid.
RuntimeError If face landmark detection failed to run.

detect_async

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detect_async(
    image: mp.Image,
    timestamp_ms: int,
    image_processing_options: Optional[mp.tasks.vision.ImageProcessingOptions] = None
) -> None

Sends live image data to perform face landmarks detection.

The results will be available via the "result_callback" provided in the FaceLandmarkerOptions. Only use this method when the FaceLandmarker is created with the live stream running mode.

Only use this method when the FaceLandmarker is created with the live stream running mode. The input timestamps should be monotonically increasing for adjacent calls of this method. This method will return immediately after the input image is accepted. The results will be available via the result_callback provided in the FaceLandmarkerOptions. The detect_async method is designed to process live stream data such as camera input. To lower the overall latency, face landmarker may drop the input images if needed. In other words, it's not guaranteed to have output per input image.

The result_callback provides:

  • The face landmarks detection results.
  • The input image that the face landmarker runs on.
  • The input timestamp in milliseconds.

Args
image MediaPipe Image.
timestamp_ms The timestamp of the input image in milliseconds.
image_processing_options Options for image processing.

Raises
ValueError If the current input timestamp is smaller than what the face landmarker has already processed.
RuntimeError If the face landmark detection failed to run.

detect_for_video

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detect_for_video(
    image: mp.Image,
    timestamp_ms: int,
    image_processing_options: Optional[mp.tasks.vision.ImageProcessingOptions] = None
) -> mp.tasks.vision.FaceLandmarkerResult

Performs face landmarks detection on the provided video frame.

Only use this method when the FaceLandmarker is created with the video running mode.

Only use this method when the FaceLandmarker is created with the video running mode. It's required to provide the video frame's timestamp (in milliseconds) along with the video frame. The input timestamps should be monotonically increasing for adjacent calls of this method.

Args
image MediaPipe Image.
timestamp_ms The timestamp of the input video frame in milliseconds.
image_processing_options Options for image processing.

Returns
The face landmarks detection results.

Raises
ValueError If any of the input arguments is invalid.
RuntimeError If face landmarker detection failed to run.

__enter__

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__enter__()

Returns self upon entering the runtime context.

__exit__

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__exit__(
    exc_type, exc_value, traceback
)

Shuts down the MediaPipe task instance on exit of the context manager.

Args
exc_type The exception type that caused the context manager to exit.
exc_value The exception value that caused the context manager to exit.
traceback The exception traceback that caused the context manager to exit.

Raises
RuntimeError If the MediaPipe FaceDetector task failed to close.