draw_landmarks_modified.py

# Copyright 2020 The MediaPipe Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""MediaPipe solution drawing utils."""

import dataclasses
import math
from typing import List, Mapping, Optional, Tuple, Union

import cv2
import matplotlib.pyplot as plt
import numpy as np

from mediapipe.framework.formats import detection_pb2
from mediapipe.framework.formats import landmark_pb2
from mediapipe.framework.formats import location_data_pb2

_PRESENCE_THRESHOLD = 0.5
_VISIBILITY_THRESHOLD = 0.5
_BGR_CHANNELS = 3

WHITE_COLOR = (224, 224, 224)
BLACK_COLOR = (0, 0, 0)
RED_COLOR = (0, 0, 255)
GREEN_COLOR = (0, 128, 0)
BLUE_COLOR = (255, 0, 0)


@dataclasses.dataclass
class DrawingSpec:
    # Color for drawing the annotation. Default to the white color.
    color: Tuple[int, int, int] = WHITE_COLOR
    # Thickness for drawing the annotation. Default to 2 pixels.
    thickness: int = 2
    # Circle radius. Default to 2 pixels.
    circle_radius: int = 2


def _normalized_to_pixel_coordinates(
        normalized_x: float, normalized_y: float, image_width: int,
        image_height: int) -> Union[None, Tuple[int, int]]:
    """Converts normalized value pair to pixel coordinates."""

    # Checks if the float value is between 0 and 1.
    def is_valid_normalized_value(value: float) -> bool:
        return (value > 0 or math.isclose(0, value)) and (value < 1 or
                                                          math.isclose(1, value))

    if not (is_valid_normalized_value(normalized_x) and
            is_valid_normalized_value(normalized_y)):
        # TODO: Draw coordinates even if it's outside of the image bounds.
        return None
    x_px = min(math.floor(normalized_x * image_width), image_width - 1)
    y_px = min(math.floor(normalized_y * image_height), image_height - 1)
    return x_px, y_px

# Changes: The project's goal is to occlude facial features, so the function
# draw_landmarks was modified to block out landmarks instead of drawing them.


def occlude_landmarks(
    image: np.ndarray,
    landmark_list: landmark_pb2.NormalizedLandmarkList,
    connections: Optional[List[Tuple[int, int]]] = None,
    landmark_drawing_spec: Optional[
        Union[DrawingSpec, Mapping[int, DrawingSpec]]
    ] = DrawingSpec(color=RED_COLOR),
    connection_drawing_spec: Union[
        DrawingSpec, Mapping[Tuple[int, int], DrawingSpec]
    ] = DrawingSpec(),
    is_drawing_landmarks: bool = True,
):
    """Draws the landmarks and the connections on the image.

    Args:
      image: A three channel BGR image represented as numpy ndarray.
      landmark_list: A normalized landmark list proto message to be annotated on
        the image.
      connections: A list of landmark index tuples that specifies how landmarks to
        be connected in the drawing.
      landmark_drawing_spec: Either a DrawingSpec object or a mapping from hand
        landmarks to the DrawingSpecs that specifies the landmarks' drawing
        settings such as color, line thickness, and circle radius. If this
        argument is explicitly set to None, no landmarks will be drawn.
      connection_drawing_spec: Either a DrawingSpec object or a mapping from hand
        connections to the DrawingSpecs that specifies the connections' drawing
        settings such as color and line thickness. If this argument is explicitly
        set to None, no landmark connections will be drawn.
      is_drawing_landmarks: Whether to draw landmarks. If set false, skip drawing
        landmarks, only contours will be drawed.

    Raises:
      ValueError: If one of the followings:
        a) If the input image is not three channel BGR.
        b) If any connetions contain invalid landmark index.
    """
    if not landmark_list:
        return
    if image.shape[2] != _BGR_CHANNELS:
        raise ValueError('Input image must contain three channel bgr data.')
    image_rows, image_cols, _ = image.shape
    idx_to_coordinates = {}
    for idx, landmark in enumerate(landmark_list.landmark):
        if ((landmark.HasField('visibility') and
             landmark.visibility < _VISIBILITY_THRESHOLD) or
            (landmark.HasField('presence') and
             landmark.presence < _PRESENCE_THRESHOLD)):
            continue
        landmark_px = _normalized_to_pixel_coordinates(landmark.x, landmark.y,
                                                       image_cols, image_rows)
        if landmark_px:
            idx_to_coordinates[idx] = landmark_px
    if connections:
        num_landmarks = len(landmark_list.landmark)
        # Draws the connections if the start and end landmarks are both visible.
        # for connection in connections:
        #     start_idx = connection[0]
        #     end_idx = connection[1]
        #     if not (0 <= start_idx < num_landmarks and 0 <= end_idx < num_landmarks):
        #         raise ValueError(f'Landmark index is out of range. Invalid connection '
        #                          f'from landmark #{start_idx} to landmark #{end_idx}.')
        #     if start_idx in idx_to_coordinates and end_idx in idx_to_coordinates:
        #         drawing_spec = connection_drawing_spec[connection] if isinstance(
        #             connection_drawing_spec, Mapping) else connection_drawing_spec
        #         cv2.line(image, idx_to_coordinates[start_idx],
        #                  idx_to_coordinates[end_idx], drawing_spec.color,
        #                  drawing_spec.thickness)
        point_set = set()
        for connection in connections:
            start_idx = connection[0]
            end_idx = connection[1]
            if not (0 <= start_idx < num_landmarks and 0 <= end_idx < num_landmarks):
                raise ValueError(f'Landmark index is out of range. Invalid connection '
                                 f'from landmark #{start_idx} to landmark #{end_idx}.')
            if start_idx in idx_to_coordinates and end_idx in idx_to_coordinates:
                point_set.add(connection[0])
                point_set.add(connection[1])
        points = np.array([idx_to_coordinates[i] for i in point_set])
        try:
            hull = cv2.convexHull(points)
            cv2.fillConvexPoly(image, hull, (0, 0, 0))
        except cv2.error:
            print("Error: Could not draw convex hull: ", points)
    # Draws landmark points after finishing the connection lines, which is
    # aesthetically better.
    if is_drawing_landmarks and landmark_drawing_spec:
        for idx, landmark_px in idx_to_coordinates.items():
            drawing_spec = landmark_drawing_spec[idx] if isinstance(
                landmark_drawing_spec, Mapping) else landmark_drawing_spec
            # White circle border
            circle_border_radius = max(drawing_spec.circle_radius + 1,
                                       int(drawing_spec.circle_radius * 1.2))
            cv2.circle(image, landmark_px, circle_border_radius, WHITE_COLOR,
                       drawing_spec.thickness)
            # Fill color into the circle
            cv2.circle(image, landmark_px, drawing_spec.circle_radius,
                       drawing_spec.color, drawing_spec.thickness)


def _normalize_color(color):
    return tuple(v / 255. for v in color)


def plot_landmarks(landmark_list: landmark_pb2.NormalizedLandmarkList,
                   connections: Optional[List[Tuple[int, int]]] = None,
                   landmark_drawing_spec: DrawingSpec = DrawingSpec(
                       color=RED_COLOR, thickness=5),
                   connection_drawing_spec: DrawingSpec = DrawingSpec(
                       color=BLACK_COLOR, thickness=5),
                   elevation: int = 10,
                   azimuth: int = 10):
    """Plot the landmarks and the connections in matplotlib 3d.

    Args:
      landmark_list: A normalized landmark list proto message to be plotted.
      connections: A list of landmark index tuples that specifies how landmarks to
        be connected.
      landmark_drawing_spec: A DrawingSpec object that specifies the landmarks'
        drawing settings such as color and line thickness.
      connection_drawing_spec: A DrawingSpec object that specifies the
        connections' drawing settings such as color and line thickness.
      elevation: The elevation from which to view the plot.
      azimuth: the azimuth angle to rotate the plot.

    Raises:
      ValueError: If any connection contains an invalid landmark index.
    """
    if not landmark_list:
        return
    plt.figure(figsize=(10, 10))
    ax = plt.axes(projection='3d')
    ax.view_init(elev=elevation, azim=azimuth)
    plotted_landmarks = {}
    for idx, landmark in enumerate(landmark_list.landmark):
        if ((landmark.HasField('visibility') and
             landmark.visibility < _VISIBILITY_THRESHOLD) or
            (landmark.HasField('presence') and
             landmark.presence < _PRESENCE_THRESHOLD)):
            continue
        ax.scatter3D(
            xs=[-landmark.z],
            ys=[landmark.x],
            zs=[-landmark.y],
            color=_normalize_color(landmark_drawing_spec.color[::-1]),
            linewidth=landmark_drawing_spec.thickness)
        plotted_landmarks[idx] = (-landmark.z, landmark.x, -landmark.y)
    if connections:
        num_landmarks = len(landmark_list.landmark)
        # Draws the connections if the start and end landmarks are both visible.
        for connection in connections:
            start_idx = connection[0]
            end_idx = connection[1]
            if not (0 <= start_idx < num_landmarks and 0 <= end_idx < num_landmarks):
                raise ValueError(f'Landmark index is out of range. Invalid connection '
                                 f'from landmark #{start_idx} to landmark #{end_idx}.')
            if start_idx in plotted_landmarks and end_idx in plotted_landmarks:
                landmark_pair = [
                    plotted_landmarks[start_idx], plotted_landmarks[end_idx]
                ]
                ax.plot3D(
                    xs=[landmark_pair[0][0], landmark_pair[1][0]],
                    ys=[landmark_pair[0][1], landmark_pair[1][1]],
                    zs=[landmark_pair[0][2], landmark_pair[1][2]],
                    color=_normalize_color(
                        connection_drawing_spec.color[::-1]),
                    linewidth=connection_drawing_spec.thickness)
    plt.show()