There are 2 alternatives to save the OpenPose output.
1. The `write_json` flag saves the people pose data using a custom JSON writer. Each JSON file has a `people` array of objects, where each object has:
1. An array `pose_keypoints` containing the body part locations and detection confidence formatted as `x1,y1,c1,x2,y2,c2,...`. The coordinates `x` and `y` can be normalized to the range [0,1], [-1,1], [0, source size], [0, output size], etc., depending on the flag `keypoint_scale`, while `c` is the confidence score in the range [0,1].
2. The arrays `face_keypoints`, `hand_left_keypoints`, and `hand_right_keypoints`, analogous to `pose_keypoints`.
3. The body part candidates before being assembled into people (if `--part_candidates` is enabled).
1. An array `pose_keypoints_2d` containing the body part locations and detection confidence formatted as `x1,y1,c1,x2,y2,c2,...`. The coordinates `x` and `y` can be normalized to the range [0,1], [-1,1], [0, source size], [0, output size], etc., depending on the flag `keypoint_scale`, while `c` is the confidence score in the range [0,1].
2. The arrays `face_keypoints_2d`, `hand_left_keypoints_2d`, and `hand_right_keypoints_2d`, analogous to `pose_keypoints_2d`.
3. The analogous 3-D arrays `body_keypoints_3d`, `face_keypoints_3d`, `hand_left_keypoints_2d`, and `hand_right_keypoints_2d` (if `--3d` is enabled, otherwise they will be empty).
4. The body part candidates before being assembled into people (if `--part_candidates` is enabled).