Пример #1
0
def main():

    parser = argparse.ArgumentParser()
    parser.add_argument("path", help="Path containing the input data")
    parser.add_argument(
        "datain",
        help=
        "Corrupted data with dimensions [Npoints OR N(Cartesian), Nshots OR N(Cartesian), Nslices, Nchannels]"
    )
    parser.add_argument(
        "ktraj",
        help=
        "K-space trajectory: [Npoints OR N(Cartesian), Nshots OR N(Cartesian)]"
    )
    parser.add_argument("fmap", help="Field map in rad/s")
    parser.add_argument("ORCmethod",
                        choices=['CPR', 'fsCPR', 'MFI'],
                        help="Correction method")
    parser.add_argument("--cart",
                        default=0,
                        choices=[0, 1],
                        dest="cart_opt",
                        help="0: non-cartesian data, 1: cartesian data")
    parser.add_argument(
        '--Lx',
        default=2,
        dest='Lx',
        help="L(frequency bins) factor with respect to minimum L")
    parser.add_argument('--grad_raster',
                        default=10e-6,
                        dest='grad_raster',
                        help="Gradient raster time")
    parser.add_argument('--TE', default=0, dest='TE', help="Echo time")
    parser.add_argument(
        '--dcf',
        default=None,
        dest='dcf',
        help="Density compensation factor for non-cartesian trajectories")

    args = parser.parse_args()
    data_in = get_data_from_file(os.path.join(args.path, args.datain))
    ktraj = get_data_from_file(os.path.join(args.path, args.ktraj))
    fmap = get_data_from_file(os.path.join(args.path,
                                           args.fmap)) / (2 * math.pi)

    ## Dimensions check
    print('Checking dimensions...')
    if data_in.shape[0] != ktraj.shape[0] or data_in.shape[1] != ktraj.shape[1]:
        raise ValueError(
            'The raw data does not agree with the k-space trajectory')
    if fmap.shape[0] != fmap.shape[1]:
        raise ValueError(
            'Image and field map should have square dimensions (NxN)')
    if len(fmap.shape) > 2:
        if fmap.shape[-1] != data_in.shape[2]:
            raise ValueError(
                'The field map dimensions do not agree with the raw data')
    if len(fmap.shape) == 2:
        fmap = np.expand_dims(fmap, -1)
        if data_in.shape[2] != 1:
            raise ValueError(
                'The field map dimensions do not agree with the raw data')

    print('OK')

    ## Sequence parameters
    N = fmap.shape[0]
    Npoints = data_in.shape[0]
    Nshots = data_in.shape[1]
    Nslices = data_in.shape[-2]
    Nchannels = data_in.shape[-1]

    t_ro = Npoints * args.grad_raster
    T = np.linspace(args.TE, args.TE + t_ro, Npoints).reshape((Npoints, 1))
    if args.cart_opt == 0:
        seq_params = {
            'N': N,
            'Npoints': Npoints,
            'Nshots': Nshots,
            't_vector': T,
            't_readout': t_ro
        }

        if args.dcf is not None:
            dcf = get_data_from_file(os.path.join(args.path,
                                                  args.dcf)).flatten()
            seq_params.update({'dcf': dcf})

    ORC_result = np.zeros((N, N, Nslices, Nchannels), dtype=complex)

    if args.ORCmethod == 'MFI':
        for ch in tqdm(range(Nchannels)):
            for sl in range(Nslices):
                if args.cart_opt == 0:
                    ORC_result[:, :, sl,
                               ch] = ORC.MFI(np.squeeze(data_in[:, :, sl, ch]),
                                             'raw', ktraj,
                                             np.squeeze(fmap[:, :, sl]),
                                             args.Lx, 1, seq_params)
                elif args.cart_opt == 1:
                    ORC_result[:, :, sl,
                               ch] = ORC.MFI(np.squeeze(data_in[:, :, sl, ch]),
                                             'raw', ktraj,
                                             np.squeeze(fmap[:, :,
                                                             sl]), args.Lx)

    elif args.ORCmethod == 'fsCPR':
        for ch in tqdm(range(Nchannels)):
            for sl in range(Nslices):
                if args.cart == 0:
                    ORC_result[:, :, sl, ch] = ORC.fs_CPR(
                        np.squeeze(data_in[:, :, sl, ch]), 'raw', ktraj,
                        np.squeeze(fmap[:, :, sl]), args.Lx, 1, seq_params)
                elif args.cart == 1:
                    ORC_result[:, :, sl, ch] = ORC.fs_CPR(
                        np.squeeze(data_in[:, :, sl, ch]), 'raw', ktraj,
                        np.squeeze(fmap[:, :, sl]), args.Lx)
    elif args.ORCmethod == 'CPR':
        for ch in tqdm(range(Nchannels)):
            for sl in range(Nslices):
                if args.cart == 0:
                    ORC_result[:, :, sl,
                               ch] = ORC.CPR(np.squeeze(data_in[:, :, sl, ch]),
                                             'raw', ktraj,
                                             np.squeeze(fmap[:, :, sl]), 1,
                                             seq_params)
                elif args.cart == 1:
                    ORC_result[:, :, sl,
                               ch] = ORC.CPR(np.squeeze(data_in[:, :, sl, ch]),
                                             'raw', ktraj,
                                             np.squeeze(fmap[:, :, sl]))

    np.save(os.path.join(args.path, 'ORC_result_' + args.ORCmethod),
            ORC_result)
Пример #2
0
Lx = 2  # Frequency segments for fs-CPR and MFI. L = Lx * Lmin
if Lx < 1:
    raise ValueError('The L factor cannot be lower that 1 (minimum L)')

CPR_result = np.zeros((N, N, Nslices, Nchannels), dtype=complex)
fsCPR_result = np.zeros((N, N, Nslices, Nchannels), dtype=complex)
MFI_result = np.zeros((N, N, Nslices, Nchannels), dtype=complex)
CPR_timing = 0
fsCPR_timing = 0
MFI_timing = 0
for ch in range(Nchannels):
    for sl in range(Nslices):
        before = time.time()
        CPR_result[:, :, sl, ch] = ORC.CPR(np.squeeze(rawdata[:, :, sl, ch]),
                                           'raw', ktraj,
                                           np.squeeze(fmap[:, :,
                                                           sl]), 1, seq_params)
        CPR_timing += time.time() - before

        print('CPR: Done with slice:' + str(sl + 1) + ', channel:' +
              str(ch + 1))
        np.save(outputs['path_correction_folder'] + 'CPR', CPR_result)

        before = time.time()
        fsCPR_result[:, :, sl,
                     ch] = ORC.fs_CPR(np.squeeze(rawdata[:, :, sl,
                                                         ch]), 'raw', ktraj,
                                      np.squeeze(fmap[:, :, sl]), Lx, 1,
                                      seq_params)
        fsCPR_timing += time.time() - before