File size: 3,190 Bytes
095b09d | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 | """Convert recorded intrinsics and optional exported ARKit poses to per-frame geometry."""
import argparse
import csv
import json
from pathlib import Path
import numpy as np
from scipy.spatial.transform import Rotation
def read_csv(path):
with path.open(encoding='utf-8-sig', newline='') as stream:
return list(csv.DictReader(line for line in stream if not line.startswith('#')))
def main():
parser = argparse.ArgumentParser(description=__doc__)
parser.add_argument('--intrinsics', type=Path, required=True)
parser.add_argument('--poses', type=Path)
parser.add_argument('--alignment', type=Path)
parser.add_argument('--parameters', type=Path)
parser.add_argument('--out', type=Path, required=True)
args = parser.parse_args()
intrinsics = read_csv(args.intrinsics)
poses = alignment = None
if args.poses:
if not args.parameters or not args.alignment:
parser.error('--poses requires --parameters and --alignment')
parameters = json.loads(args.parameters.read_text(encoding='utf-8-sig'))
pose_info = parameters['pose']
if (pose_info['world_alignment'] != 'gravity' or
pose_info['convention'] != 'T_world_camera (parent_from_child)' or
pose_info['camera_coordinates'] != 'OpenCV/Rerun RDF (x right, y down, z forward)'):
raise ValueError('Expected gravity-aligned T_world_camera already exported in camera RDF coordinates')
poses, alignment = read_csv(args.poses), read_csv(args.alignment)
if len(alignment) != len(intrinsics):
raise ValueError('Intrinsics and alignment must have the same frame count')
rows = []
for index, params in enumerate(intrinsics):
if int(params['frame_idx']) != index:
raise ValueError('Intrinsics frame_idx must start at zero and be in order')
row = dict(frame_idx=index, width=params['native_width_px'], height=params['native_height_px'],
fx=params['native_fx_px'], fy=params['native_fy_px'],
cx=params['native_cx_px'], cy=params['native_cy_px'])
if poses is not None:
match = alignment[index]
pose = poses[int(match['arkit_row_index'])]
if int(match['frame_idx']) != index or abs(float(pose['sensor_sec'])-float(params['sensor_sec'])) > 1e-5:
raise ValueError(f'Pose/intrinsics alignment mismatch at frame {index}')
if pose['tracking_state'] != 'normal':
raise ValueError(f'ARKit tracking is not normal at frame {index}')
q = np.array([float(pose[key]) for key in ['qx','qy','qz','qw']])
q /= np.linalg.norm(q)
up = Rotation.from_quat(q).as_matrix().T @ np.array([0.,1.,0.])
row.update(stamp=match['stamp'], up_x=up[0], up_y=up[1], up_z=up[2])
rows.append(row)
with args.out.open('w', encoding='utf-8', newline='') as stream:
writer = csv.DictWriter(stream, fieldnames=list(rows[0]))
writer.writeheader()
writer.writerows(rows)
print(f'Saved {len(rows)} frames; gravity aligned: {poses is not None}')
if __name__ == '__main__':
main()
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