| """ |
| Render OpenPose keypoints. |
| Code was ported to Python from the official C++ implementation https://github.com/CMU-Perceptual-Computing-Lab/openpose/blob/master/src/openpose/utilities/keypoint.cpp |
| """ |
| import cv2 |
| import math |
| import numpy as np |
| from typing import List, Tuple |
|
|
| def get_keypoints_rectangle(keypoints: np.array, threshold: float) -> Tuple[float, float, float]: |
| """ |
| Compute rectangle enclosing keypoints above the threshold. |
| Args: |
| keypoints (np.array): Keypoint array of shape (N, 3). |
| threshold (float): Confidence visualization threshold. |
| Returns: |
| Tuple[float, float, float]: Rectangle width, height and area. |
| """ |
| valid_ind = keypoints[:, -1] > threshold |
| if valid_ind.sum() > 0: |
| valid_keypoints = keypoints[valid_ind][:, :-1] |
| max_x = valid_keypoints[:,0].max() |
| max_y = valid_keypoints[:,1].max() |
| min_x = valid_keypoints[:,0].min() |
| min_y = valid_keypoints[:,1].min() |
| width = max_x - min_x |
| height = max_y - min_y |
| area = width * height |
| return width, height, area |
| else: |
| return 0,0,0 |
|
|
| def render_keypoints(img: np.array, |
| keypoints: np.array, |
| pairs: List, |
| colors: List, |
| thickness_circle_ratio: float, |
| thickness_line_ratio_wrt_circle: float, |
| pose_scales: List, |
| threshold: float = 0.1) -> np.array: |
| """ |
| Render keypoints on input image. |
| Args: |
| img (np.array): Input image of shape (H, W, 3) with pixel values in the [0,255] range. |
| keypoints (np.array): Keypoint array of shape (N, 3). |
| pairs (List): List of keypoint pairs per limb. |
| colors: (List): List of colors per keypoint. |
| thickness_circle_ratio (float): Circle thickness ratio. |
| thickness_line_ratio_wrt_circle (float): Line thickness ratio wrt the circle. |
| pose_scales (List): List of pose scales. |
| threshold (float): Only visualize keypoints with confidence above the threshold. |
| Returns: |
| (np.array): Image of shape (H, W, 3) with keypoints drawn on top of the original image. |
| """ |
| img_orig = img.copy() |
| width, height = img.shape[1], img.shape[2] |
| area = width * height |
|
|
| lineType = 8 |
| shift = 0 |
| numberColors = len(colors) |
| thresholdRectangle = 0.1 |
|
|
| person_width, person_height, person_area = get_keypoints_rectangle(keypoints, thresholdRectangle) |
| if person_area > 0: |
| ratioAreas = min(1, max(person_width / width, person_height / height)) |
| thicknessRatio = np.maximum(np.round(math.sqrt(area) * thickness_circle_ratio * ratioAreas), 2) |
| thicknessCircle = np.maximum(1, thicknessRatio if ratioAreas > 0.05 else -np.ones_like(thicknessRatio)) |
| thicknessLine = np.maximum(1, np.round(thicknessRatio * thickness_line_ratio_wrt_circle)) |
| radius = thicknessRatio / 2 |
|
|
| img = np.ascontiguousarray(img.copy()) |
| for i, pair in enumerate(pairs): |
| index1, index2 = pair |
| if keypoints[index1, -1] > threshold and keypoints[index2, -1] > threshold: |
| thicknessLineScaled = int(round(min(thicknessLine[index1], thicknessLine[index2]) * pose_scales[0])) |
| colorIndex = index2 |
| color = colors[colorIndex % numberColors] |
| keypoint1 = keypoints[index1, :-1].astype(np.int) |
| keypoint2 = keypoints[index2, :-1].astype(np.int) |
| cv2.line(img, tuple(keypoint1.tolist()), tuple(keypoint2.tolist()), tuple(color.tolist()), thicknessLineScaled, lineType, shift) |
| for part in range(len(keypoints)): |
| faceIndex = part |
| if keypoints[faceIndex, -1] > threshold: |
| radiusScaled = int(round(radius[faceIndex] * pose_scales[0])) |
| thicknessCircleScaled = int(round(thicknessCircle[faceIndex] * pose_scales[0])) |
| colorIndex = part |
| color = colors[colorIndex % numberColors] |
| center = keypoints[faceIndex, :-1].astype(np.int) |
| cv2.circle(img, tuple(center.tolist()), radiusScaled, tuple(color.tolist()), thicknessCircleScaled, lineType, shift) |
| return img |
|
|
| def render_body_keypoints(img: np.array, |
| body_keypoints: np.array) -> np.array: |
| """ |
| Render OpenPose body keypoints on input image. |
| Args: |
| img (np.array): Input image of shape (H, W, 3) with pixel values in the [0,255] range. |
| body_keypoints (np.array): Keypoint array of shape (N, 3); 3 <====> (x, y, confidence). |
| Returns: |
| (np.array): Image of shape (H, W, 3) with keypoints drawn on top of the original image. |
| """ |
|
|
| thickness_circle_ratio = 1./75. * np.ones(body_keypoints.shape[0]) |
| thickness_line_ratio_wrt_circle = 0.75 |
| pairs = [] |
| pairs = [1,8,1,2,1,5,2,3,3,4,5,6,6,7,8,9,9,10,10,11,8,12,12,13,13,14,1,0,0,15,15,17,0,16,16,18,14,19,19,20,14,21,11,22,22,23,11,24] |
| pairs = np.array(pairs).reshape(-1,2) |
| colors = [255., 0., 85., |
| 255., 0., 0., |
| 255., 85., 0., |
| 255., 170., 0., |
| 255., 255., 0., |
| 170., 255., 0., |
| 85., 255., 0., |
| 0., 255., 0., |
| 255., 0., 0., |
| 0., 255., 85., |
| 0., 255., 170., |
| 0., 255., 255., |
| 0., 170., 255., |
| 0., 85., 255., |
| 0., 0., 255., |
| 255., 0., 170., |
| 170., 0., 255., |
| 255., 0., 255., |
| 85., 0., 255., |
| 0., 0., 255., |
| 0., 0., 255., |
| 0., 0., 255., |
| 0., 255., 255., |
| 0., 255., 255., |
| 0., 255., 255.] |
| colors = np.array(colors).reshape(-1,3) |
| pose_scales = [1] |
| return render_keypoints(img, body_keypoints, pairs, colors, thickness_circle_ratio, thickness_line_ratio_wrt_circle, pose_scales, 0.1) |
|
|
| def render_openpose(img: np.array, |
| body_keypoints: np.array) -> np.array: |
| """ |
| Render keypoints in the OpenPose format on input image. |
| Args: |
| img (np.array): Input image of shape (H, W, 3) with pixel values in the [0,255] range. |
| body_keypoints (np.array): Keypoint array of shape (N, 3); 3 <====> (x, y, confidence). |
| Returns: |
| (np.array): Image of shape (H, W, 3) with keypoints drawn on top of the original image. |
| """ |
| img = render_body_keypoints(img, body_keypoints) |
| return img |
|
|
