Files
calibration/tools/export_motion_pairs_for_viz.py

112 lines
3.6 KiB
Python

#!/usr/bin/env python3
"""Build motion_pairs.json next to an existing summary without re-solving extrinsic.
Use this once for older calibration outputs that predate automatic pair caching.
"""
from __future__ import annotations
import argparse
import json
import sys
from pathlib import Path
import numpy as np
ROOT = Path(__file__).resolve().parents[1]
if str(ROOT) not in sys.path:
sys.path.insert(0, str(ROOT))
from imu_lidar.imu_audit import audit_imu
from imu_lidar.imu_io import load_imu_samples
from imu_lidar.keyframes import build_keyframes
from imu_lidar.lidar_io import load_lidar_frames
from imu_lidar.motion_pairs import build_motion_pairs
from imu_lidar.motion_pairs_io import build_motion_pairs_payload, save_motion_pairs
def _load_summary_meta(summary_path: Path) -> tuple[float, np.ndarray, str]:
summary = json.loads(summary_path.read_text(encoding="utf-8"))
delta_t = float(summary.get("time_offset_s") or 0.0)
session = (summary.get("details") or {}).get("sessions", [{}])[0]
session_id = str(session.get("session_id") or summary_path.parent.name)
bias = np.asarray(
(session.get("imu_audit") or {}).get("gyro_bias_rad_s")
or (session.get("joint") or {}).get("gyro_bias_rad_s")
or [0.0, 0.0, 0.0],
dtype=float,
).reshape(3)
return delta_t, bias, session_id
def export_one(
*,
lidar: Path,
imu: Path,
summary: Path,
output: Path | None,
min_rotation_deg: float,
min_translation_m: float,
) -> Path:
delta_t, bias_from_summary, session_id = _load_summary_meta(summary)
imu_series = load_imu_samples(imu)
# Prefer freshly audited bias if summary bias is missing/zeros.
if float(np.linalg.norm(bias_from_summary)) < 1e-12:
bias = audit_imu(imu_series).gyro_bias_rad_s
else:
bias = bias_from_summary
frames = load_lidar_frames(lidar)
keyframes = build_keyframes(
frames,
min_translation_m=min_translation_m,
min_rotation_deg=min_rotation_deg,
)
pair_set = build_motion_pairs(
session_id=session_id,
keyframes=list(keyframes.frames),
keyframe_indices=keyframes.indices,
imu=imu_series,
delta_t_s=delta_t,
gyro_bias_rad_s=bias,
min_rotation_deg=min_rotation_deg,
min_translation_m=min_translation_m,
)
prepared = [
{
"session_id": session_id,
"time_offset_s": delta_t,
"gyro_bias_rad_s": np.asarray(bias, dtype=float).reshape(3),
"pairs": pair_set.pairs,
}
]
payload = build_motion_pairs_payload(prepared_sessions=prepared)
out = output or (summary.parent / "motion_pairs.json")
save_motion_pairs(out, payload)
print(f"wrote {out} ({len(pair_set.pairs)} pairs, session={session_id}, dt={delta_t:.6f})")
return out
def main() -> int:
parser = argparse.ArgumentParser(description=__doc__)
parser.add_argument("--lidar", type=Path, required=True)
parser.add_argument("--imu", type=Path, required=True)
parser.add_argument("--summary", type=Path, required=True)
parser.add_argument("--output", type=Path, default=None, help="Default: <summary_dir>/motion_pairs.json")
parser.add_argument("--min-pair-rotation-deg", type=float, default=2.0)
parser.add_argument("--min-pair-translation-m", type=float, default=0.3)
args = parser.parse_args()
export_one(
lidar=args.lidar,
imu=args.imu,
summary=args.summary,
output=args.output,
min_rotation_deg=args.min_pair_rotation_deg,
min_translation_m=args.min_pair_translation_m,
)
return 0
if __name__ == "__main__":
raise SystemExit(main())