2d and 3d joints positions

[Marlod390]

I tried to use the smpl parameter to calculate the position of 3d joints in order to compare with the data under the 3d_joints key, but found that the two data are different. At the same time, when I visualized the 2d joints on the original image, I also found that their positions did not match the actual ones. So I want to know how the 3d joints and 2d joints are calculated. Thanks in advance

[geopavlakos]

You can follow the code in the forward_step to see how we calculate the 3D joints and project them to the image. In what way were the 3D and 2D joints different from the ones you calculated?

[Marlod390]

Thank for your reply. This is the code i use to visualize the first 25 predicted 2d joints on the original frame.
`import joblib import cv2 import matplotlib.pyplot as plt import numpy as np

data = joblib.load('/home/markusc/Videos/panda_test/video/output2/webvid/medium/3/4dhumans/3_4dhumans.pkl')

first_key = next(iter(data.keys())) joints_2d_1 = data[first_key]['2d_joints'][0][:252] joints_2d_2 = data[first_key]['2d_joints'][1][:252]

image_path = '/home/markusc/Videos/panda_test/video/3/json_files/multiple/3/0_pose.png' image = cv2.imread(image_path) image = cv2.cvtColor(image, cv2.COLOR_BGR2RGB)

img_height, imgwidth, = image.shape

joints_2d_1 = joints_2d_1.reshape(-1, 2) joints_2d_2 = joints_2d_2.reshape(-1, 2)

joints_2d_1[:, 0] = img_width joints_2d_1[:, 1] = img_height joints_2d_2[:, 0] = img_width joints_2d_2[:, 1] = img_height

print("Joints 2D 1 positions:") print(joints_2d_1)

print("Joints 2D 2 positions:") print(joints_2d_2)

plt.figure(figsize=(10, 10)) plt.imshow(image)

for idx, joint in enumerate(joints_2d_1): if idx == 0: plt.scatter(joint[0], joint[1], s=100, c='yellow', marker='o') else: plt.scatter(joint[0], joint[1], s=30, c='red', marker='o') plt.text(joint[0], joint[1], str(idx), fontsize=12, color='red')

for idx, joint in enumerate(joints_2d_2): if idx == 0: plt.scatter(joint[0], joint[1], s=100, c='green', marker='o') else: plt.scatter(joint[0], joint[1], s=30, c='blue', marker='o') plt.text(joint[0], joint[1], str(idx), fontsize=12, color='blue')

plt.title('2D Joints on Image - First Frame') plt.axis('off') plt.show()`

And the result is as follow