how to project 3d mesh points to 2d points.

[tengshaofeng]

@geopavlakos @dimtzionas @vchoutas @MichaelJBlack @nghorbani Dears,When I finish the fitting, I print the camera parameter like:

So I write a code like this
"
def get_camera_intrinsic(focal_length, camera_center):
K = np.array([
[focal_length, 0, camera_center[0]],
[0, focal_length, camera_center[1]],
[0, 0, 1]
], dtype=np.float32)
return K

def project_points(mesh_points, camera_transl, camera_intrinsic):
R = np.eye(3)
t = camera_transl.reshape(3, 1)
T = np.hstack((R, t))
ones = np.ones((mesh_points.shape[0], 1))
homogenous_points = np.hstack((mesh_points, ones))
camera_points = homogenous_points.dot(T.T)
projected_points = camera_points.dot(camera_intrinsic.T)
projected_points_2d = projected_points[:, :2] / projected_points[:, 2, np.newaxis]
return projected_points_2d[:, :2] # 只取x, y坐标

相机参数

camera_center = np.array([800., 600.], dtype=np.float32)
camera_transl = np.array([-0.04409692, 0.26306236, 8.006923], dtype=np.float32)
focal_length = 5000.0
K = get_camera_intrinsic(focal_length, camera_center)
out_mesh = trimesh.load_mesh("../OUTPUT_FOLDER/meshes/01_img/000.obj")
mesh_points = np.array(out_mesh.vertices)

投影三维点到二维

projected_points_2d = project_points(mesh_points, camera_transl, K)
projected_points_2d[:, 1] = H - 1 - projected_points_2d[:, 1]

打印投影结果

print(projected_points_2d)
color = (0, 0, 255) # BGR格式

对每个二维点进行绘制

img = cv2.imread("../DATA_FOLDER/images/01_img.jpg")
for point in projected_points_2d.astype(int):
cv2.circle(img, tuple(point), radius=1, color=color, thickness=-1) # thickness=-1 表示填充圆
cv2.imwrite('projected_points_cv2.png', img)
"
But I get result like this:

What is wrong? Can u help me to fix my code?