def _get_frame_gt(dataset_objects: List[bpy.types.Mesh],
unit_scaling: float,
ignore_dist_thres: float,
destination_frame: List[str] = ["X", "-Y", "-Z"]):
""" Returns GT pose annotations between active camera and objects.
:param dataset_objects: Save annotations for these objects.
:param unit_scaling: 1000. for outputting poses in mm
:param ignore_dist_thres: Distance between camera and object after which object is ignored. Mostly due to failed physics.
:param destination_frame: Transform poses from Blender internal coordinates to OpenCV coordinates
:return: A list of GT camera-object pose annotations for scene_gt.json
"""
H_c2w_opencv = Matrix(
WriterUtility.get_cam_attribute(
bpy.context.scene.camera,
'cam2world_matrix',
local_frame_change=destination_frame))
frame_gt = []
for obj in dataset_objects:
H_m2w = Matrix(
WriterUtility.get_common_attribute(obj, 'matrix_world'))
cam_H_m2c = H_c2w_opencv.inverted() @ H_m2w
cam_R_m2c = cam_H_m2c.to_quaternion().to_matrix()
cam_t_m2c = cam_H_m2c.to_translation()
# ignore examples that fell through the plane
if not np.linalg.norm(list(cam_t_m2c)) > ignore_dist_thres:
cam_t_m2c = list(cam_t_m2c * unit_scaling)
frame_gt.append({
'cam_R_m2c':
list(cam_R_m2c[0]) + list(cam_R_m2c[1]) +
list(cam_R_m2c[2]),
'cam_t_m2c':
cam_t_m2c,
'obj_id':
obj["category_id"]
})
else:
print('ignored obj, ', obj["category_id"], 'because either ')
print(
'(1) it is further away than parameter "ignore_dist_thres: ",',
ignore_dist_thres)
print(
'(e.g. because it fell through a plane during physics sim)'
)
print('or')
print('(2) the object pose has not been given in meters')
return frame_gt
def _get_frame_camera(save_world2cam,
depth_scale=1.0,
unit_scaling=1000.,
destination_frame=["X", "-Y", "-Z"]):
""" Returns camera parameters for the active camera.
:param save_world2cam: If true, camera to world transformations "cam_R_w2c", "cam_t_w2c" are saved in scene_camera.json
:param depth_scale: Multiply the uint16 output depth image with this factor to get depth in mm.
:param unit_scaling: 1000. for outputting poses in mm
:param destination_frame: Transform poses from Blender internal coordinates to OpenCV coordinates
:return: dict containing info for scene_camera.json
"""
cam_K = WriterUtility.get_cam_attribute(bpy.context.scene.camera,
'cam_K')
frame_camera_dict = {
'cam_K': cam_K[0] + cam_K[1] + cam_K[2],
'depth_scale': depth_scale
}
if save_world2cam:
H_c2w_opencv = Matrix(
WriterUtility.get_cam_attribute(
bpy.context.scene.camera,
'cam2world_matrix',
local_frame_change=destination_frame))
H_w2c_opencv = H_c2w_opencv.inverted()
R_w2c_opencv = H_w2c_opencv.to_quaternion().to_matrix()
t_w2c_opencv = H_w2c_opencv.to_translation() * unit_scaling
frame_camera_dict['cam_R_w2c'] = list(R_w2c_opencv[0]) + list(
R_w2c_opencv[1]) + list(R_w2c_opencv[2])
frame_camera_dict['cam_t_w2c'] = list(t_w2c_opencv)
return frame_camera_dict
def _write_camera(camera_path: str, depth_scale: float = 1.0):
""" Writes camera.json into dataset_dir.
:param camera_path: Path to camera.json
:param depth_scale: Multiply the uint16 output depth image with this factor to get depth in mm.
"""
cam_K = WriterUtility.get_cam_attribute(bpy.context.scene.camera,
'cam_K')
camera = {
'cx': cam_K[0][2],
'cy': cam_K[1][2],
'depth_scale': depth_scale,
'fx': cam_K[0][0],
'fy': cam_K[1][1],
'height': bpy.context.scene.render.resolution_y,
'width': bpy.context.scene.render.resolution_x
}
BopWriterUtility._save_json(camera_path, camera)