def read_data(flags):
    intrinsics = np.loadtxt(os.path.join(flags.path, 'camera_matrix.csv'), delimiter=',')
    odometry = np.loadtxt(os.path.join(flags.path, 'odometry.csv'), delimiter=',', skiprows=1)
    poses = []

    for line in odometry:
        # timestamp, frame, x, y, z, qx, qy, qz, qw
        position = line[2:5]
        quaternion = line[5:]
        T_WC = np.eye(4)
        T_WC[:3, :3] = Rotation.from_quat(quaternion).as_matrix()
        T_WC[:3, 3] = position
        poses.append(T_WC)
    depth_dir = os.path.join(flags.path, 'depth')
    depth_frames = [os.path.join(depth_dir, p) for p in sorted(os.listdir(depth_dir))]
    depth_frames = [f for f in depth_frames if '.npy' in f or '.png' in f]
    return { 'poses': poses, 'intrinsics': intrinsics, 'depth_frames': depth_frames }